Level meter

Abstract

To provide a level meter which allows a user to easily grasp a relative position of threshold of a level with respect to a container visually when the user sets the threshold.SOLUTION: A display 20 of a level meter 10 displays a bar display 22 whose length extends and retracts according to a value of a level of an object to be contained in a container. The display 20 also displays a relative position with respect to the container, of a plurality of level set values related to the level together with the bar display 22.SELECTED DRAWING: Figure 42

Description

[Technical field]

[0001] The present invention relates to a level meter for measuring the level of a contained object. [Background technology]

[0002] In containers that store fluid substances such as liquids, powders, and granules, level gauges are sometimes used to measure the height of the interface of the substance, i.e., the level (liquid surface level, powder top surface level, etc.). Such level gauges have a function for specifying the measurement conditions, that is, a function for setting the conditions under which the level is measured. For example, the level gauge described in Patent Document 1 has a setting mode for determining the values ​​of parameters for specifying the measurement conditions. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2014-002091 A Summary of the Invention [Problem to be solved by the invention]

[0004] In conventional level gauges, the values ​​of parameters for defining the measurement conditions are displayed as characters and numbers. For example, the level gauge in Patent Document 1 is provided with a display unit, and in each setting mode, the settable parameters are displayed on the display unit as characters and numbers.

[0005] However, when parameters are displayed only as text and numerical values, it is difficult for the user to visually grasp the relationship between the parameters and the container. For example, when a threshold value for output determination is set in the setting mode, the user must calculate and determine the relative position of the threshold value with respect to the entire container (or the percentage of the full value) based on the displayed numerical value and the capacity of the container. In other words, the user cannot visually grasp the relative position of the threshold value with respect to the container just by looking at the numerical value of the threshold value displayed in the setting mode.

[0006] In view of the above problems, an object of the present invention is to provide a level meter that allows a user to easily visually grasp the relative position of a level setting value for a container. [Means for solving the problem]

[0007] In order to solve the above problems, a level meter as an example of an embodiment of the present invention is a level meter that is installed at the top of a container facing the bottom surface of the container to measure the level of the contents contained in the container, and is equipped with a transceiver unit that includes a transmitting circuit that transmits a measurement signal for measuring the level and a receiving circuit that receives a reflected signal resulting from the measurement signal being reflected by the contents, a level determination unit that determines the level based on the reflected signal received by the receiving circuit and container information related to the container, a setting unit that sequentially sets the container information and a number of level setting values ​​related to the level determined by the level determination unit, and a display unit that displays the relative position of the level setting value with respect to the container based on the level determined by the level determination unit, the container information, and the level setting value, together with a bar display whose length expands or contracts depending on the level value determined by the level determination unit. Effect of the Invention

[0008] According to the present invention, the user can easily visually grasp the relative position of the level setting value with respect to the container by checking the display unit. [Brief description of the drawings]

[0009] [Figure 1] FIG. [Diagram 2] Cross-sectional view of a level meter. [Diagram 3] FIG. 2 is a diagram showing a state in which a level gauge is attached to a container that contains an object. [Figure 4] FIG. 2 is a block diagram illustrating an example of the relationship between components of a level meter. [Diagram 5] FIG. 2 is a diagram showing an example of the configuration of a radar control unit and a transmitting / receiving unit. [Figure 6] FIG. 4 is a diagram showing the relationship between a measurement signal and a reflected signal. [Figure 7] FIG. 4 is a diagram showing state transitions of a level meter. [Figure 8] 5A to 5C are diagrams showing screen transitions on the display unit in the initial setting. [Figure 9] 5A to 5C are diagrams showing screen transitions on the display unit during operation setting. [Figure 10] 6A to 6C are diagrams showing screen transitions on the display unit during scaling setting. [Figure 11] FIG. [Figure 12] FIG. 13 is a diagram showing a setup start confirmation screen. [Figure 13] FIG. [Figure 14] FIG. [Figure 15] FIG. 13 is a diagram showing a distance unit setting screen. [Figure 16] FIG. 13 is a diagram showing a scaling confirmation screen. [Figure 17] FIG. [Figure 18] FIG. 13 is a diagram showing an upper surface distance setting screen. [Figure 19] FIG. 13 is a diagram showing a first threshold setting screen. [Figure 20] FIG. 13 is a diagram showing an output logic setting screen for the first threshold value. [Figure 21] FIG. 13 is a diagram showing a second threshold setting screen. [Figure 22] FIG. 13 is a diagram showing an indicator light pattern setting screen. [Figure 23]13A to 13C are diagrams showing changes due to animation on the indicator light pattern setting screen. [Figure 24] FIG. 4 is a diagram showing a second indicator light pattern. [Diagram 25] FIG. 13 is a diagram showing a setup completion confirmation screen. [Figure 26] FIG. [Figure 27] FIG. [Figure 28] FIG. 13 is a diagram showing a tank shape setting screen. [Figure 29] FIG. [Diagram 30] Diagram showing spherical tank options. [Diagram 31] FIG. 13 is a diagram showing a bottom distance setting screen for a spherical tank. [Diagram 32] FIG. 13 is a diagram showing a screen for setting the top surface distance of a spherical tank. [Diagram 33] FIG. 13 is a diagram showing a capacity setting screen for a spherical tank. [Diagram 34] Diagram showing options for horizontal cylindrical tanks. [Diagram 35] Diagram showing options for conical bottom tanks. [Diagram 36] FIG. 13 shows a bottom height setting screen for a conical bottom tank. [Figure 37] Diagram showing options for square pyramidal bottom tanks. [Figure 38] Diagram showing sloped bottom tank options. [Figure 39] A diagram showing multi-point correction options. [Diagram 40] FIG. 13 is a diagram showing a multi-point correction screen for multi-point correction. [Diagram 41] FIG. 13 is a diagram showing an example of a tank shape that supports multi-point correction. [Diagram 42] FIG. 4 is a diagram showing the display unit in a measurement mode. [Diagram 43] FIG. [Diagram 44] FIG. 4 is a diagram showing various setting screens. [Diagram 45] FIG. 4 is a diagram showing an input / output setting screen to which the user transitions from various setting screens. [Diagram 46] FIG. 11 is a perspective view showing another example of a level meter. [Figure 47] FIG. 11 is a cross-sectional view of another example of a level meter. [Figure 48] FIG. 13 is a diagram showing another example of the bottom distance setting screen. [Figure 49] FIG. 13 is a diagram showing another example of the second threshold setting screen. [Figure 50] FIG. 13 is a diagram showing another example of the output logic setting screen for the second threshold value. [Figure 51] FIG. 13 is a diagram showing another example of the indicator light pattern setting screen. [Figure 52] FIG. 13 is a diagram showing another example of the setup completion confirmation screen. [Diagram 53] FIG. 11 is a perspective view showing still another example of a level meter. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference symbols, and basically the description will not be repeated. In the following description, terms meaning positions or directions such as front, back, left, right, up, and down may be used, but these terms are used for convenience to facilitate understanding of the embodiment. Unless otherwise clearly stated, these terms are not limited to front, back, left, right, up, and down in the strict geometric sense.

[0011] Hereinafter, a level meter 10 as an example of an embodiment of the present invention will be described with reference to the drawings. First, an example of the structure and usage state of the level meter 10 will be described with reference to Figs. 1, 2, and 3. Fig. 1 shows a perspective view of the level meter 10 of this embodiment. Fig. 2 shows a cross-sectional view of the level meter 10 of Fig. 1. Fig. 3 shows a state in which the level meter 10 is attached to a container 70 (e.g., a tank) that contains an item 72.

[0012] The level meter 10 is a device that measures the level Y of the contained object 72 (e.g., liquid, powder, granules, etc.) that is the measurement target. The level Y to be measured is the height of the interface 74 of the contained object 72 in the container 70. A specific example of the level Y is the distance from the bottom of the container 70 to the liquid surface of the liquid contained in the container 70. A measurement axis is set in the level meter 10, and the level meter 10 measures the level Y along the measurement axis.

[0013] As an example of a usage state of the level meter 10, a container 70 in FIG. 3 contains a liquid (water, oil, chemical liquid, etc.) that becomes the contents 72 in a liquid treatment facility. For example, when the contents 72 in the container 70 are supplied to a liquid treatment process, the level Y of the contents 72 in the container 70 decreases. Also, when the contents 72 are replenished to the container 70, the level Y of the contents 72 in the container 70 increases. For example, a water inlet 75 is provided on the outer wall (upper wall in FIG. 3) of the container 70. A water inlet pipe 76 is fluidly connected to the container 70 through the water inlet 75. The water inlet pipe 76 is connected to a water inlet device 78 (e.g., a device including a pump, a valve, etc.) provided outside the container 70. The water inlet device 78 is a device that supplies (injects) the contents 72 into the container 70 from outside the container 70. The water inlet device 78 adjusts the amount of water to be poured into the container 70 according to the level Y of the contents 72 in the container 70. The water injection device 78 also stops pouring water depending on the level Y of the contents 72 in the container 70. The water injection device 78 controls the replenishment of the contents 72 to the container 70 depending on the level Y of the contents 72 in the container 70, which decreases as the contents 72 is consumed by, for example, a liquid treatment process, so that the level Y of the contents 72 in the container 70 is within a predetermined range.

[0014] The level meter 10 in Fig. 1 has a housing 15 including a base portion 15a and a terminal portion 21. The base portion 15a is disposed on one end side (lower side) of the housing 15 in the longitudinal direction A (direction of the measurement axis). The terminal portion 21 is disposed on the other end side in the longitudinal direction A. In Fig. 1, the display portion 20 is provided on the terminal portion 21. Moreover, the terminal portion 21 is separable from the base portion 15a. The base portion 15a is cylindrical, while the terminal portion 21 is prismatic.

[0015] The terminal unit 21 may be fixed to the base unit 15a by a fastening screw on the rear side of the display unit 20. In addition, a connection connector that transmits an electric signal between the base unit 15a and the terminal unit 21 may be provided. For example, one of a pair of connection connectors may be provided on the base unit 15a, and the other of the pair of connection connectors may be provided on the terminal unit 21. By connecting the pair of connection connectors to each other, it becomes possible to transmit and receive electric signals between the base unit 15a and the terminal unit 21.

[0016] The sensor unit 16 is disposed at one end side in the longitudinal direction A of the housing 15 (the lower side in FIG. 1). Hereinafter, one end (lower end) of the sensor unit 16 in the longitudinal direction A will be referred to as the measurement end 40. As shown in FIG. 2, a dielectric lens 48 is disposed at the measurement end 40. Hereinafter, the one end side in the longitudinal direction A of the level meter 10 may be referred to as the lower side, and the other end side in the longitudinal direction A may be referred to as the upper side.

[0017] 3, the sensor unit 16 in Fig. 1 measures the level Y of the contained item 72 with one end in the longitudinal direction A facing the contained item 72. For example, when the level meter 10 measures the height of the liquid surface (interface 74) of the liquid, the longitudinal direction A of the level meter 10 is oriented in the same direction as the change in the height of the liquid surface, i.e., the vertical direction (height direction, gravity direction).

[0018] The level meter 10 in FIG. 3 transmits radio waves serving as a measurement signal Tx from the measurement end 40 toward the contained object 72. Then, a reflected signal Rx resulting from the measurement signal Tx being reflected by an interface 74 of the contained object 72 is received by the measurement end 40. The level meter 10 calculates the level Y of the contained object 72 based on the measurement signal Tx and the reflected signal Rx. For example, when performing measurement using a Time of Flight (ToF) method, the level meter 10 calculates a distance YA from the measurement end 40 to the interface 74 based on the difference between the measurement signal Tx and the reflected signal Rx, and calculates the level Y based on the distance YA. Also, for example, when performing measurement using a radar method using a Frequency Modulated Continuous Wave (FMCW), the level meter 10 calculates a distance YA from the measurement end 40 to the interface 74 based on the frequency of a waveform obtained by mixing the measurement signal Tx and the reflected signal Rx, and calculates the level Y based on the distance YA.

[0019] As shown in FIG. 1, the sensor unit 16 has a mounting screw portion 18 with a thread engraved on the surface of a cylinder, above the measurement end 40. Furthermore, a mounting portion 17 with a diameter larger than that of the mounting screw portion 18 is provided above the mounting screw portion 18. The mounting portion 17 in FIG. 1 has a nut-like shape. Note that the mounting portion 17 may have any structure that allows the level gauge 10 to be mounted to an object (such as a container 70 that contains liquid), and is not limited to a nut-like shape. For example, the mounting portion 17 may have a cylindrical shape with a non-slip protrusion. The non-slip protrusion of the mounting portion 17 serves as a non-slip protrusion when the level gauge 10 is mounted or removed (rotational attachment / detachment) while rotating around the longitudinal direction A relative to the object. In addition, instead of the mounting portion 17 and the mounting screw portion 18, a mounting flange for mounting the level gauge 10 to the object may be formed. In addition, even when a mounting flange is formed, the mounting portion 17 and the mounting screw portion 18 may be provided in addition to the mounting flange.

[0020] The level gauge 10 in FIG. 3 is attached to the upper side of the container 70. An attachment hole 71 is provided on the upper side of the container 70. The attachment hole 71 is a screw hole, and the level gauge 10 is attached to the container 70 by screwing the attachment screw portion 18 of the level gauge 10 into the attachment hole 71. For example, a user of the level gauge 10 can screw the attachment screw portion 18 into the attachment hole 71 by rotating the nut-shaped attachment portion 17 with the tip of the attachment screw portion 18 aligned with the attachment hole 71. Note that the structure for attaching the level gauge 10 to the container 70 is not limited to this. For example, the attachment hole 71 may not have a thread, and a separate nut may be screwed into the attachment screw portion 18 exposed inside the container 70, thereby attaching the level gauge 10 to the container 70. Also, the top surface of the container 70 may be open, and the level gauge 10 may be attached to a mounting fixture provided above the container 70 using a nut and the attachment screw portion 18. Furthermore, the method of attaching the level meter 10 to the container 70 is not limited to screwing using the mounting thread portion 18, and threads do not have to be formed on the outer circumferential surface of the sensor portion 16. For example, the level meter 10 may be attached to the container 70 by providing a flange on either or both of the level meter 10 and the container 70 and fastening the flange to the level meter 10 or the container 70 with a bolt.

[0021] A display unit 20 is provided on the surface of the terminal unit 21 arranged on the upper side of the housing 15. The display unit 20 preferably includes an active matrix display device (active matrix display) capable of displaying various information. For example, the display unit 20 includes an LCD (Liquid Crystal Display). In particular, the display unit 20 preferably includes an LCD capable of color display (display in multiple colors).

[0022] The display unit 20 may also be a two-line reflective color liquid crystal display that transmits and receives power and communicates data using two power lines. A two-line display communicates data by varying the magnitude of the current that travels through the power lines. For example, the current consumption of the power lines varies in the range of 4-20 mA. The content of the data being transmitted and received is represented by the magnitude of this current consumption. A reflective display allows a user to view the displayed content by external light reflected on its surface. A two-line display requires a small amount of power to be used, but a two-line reflective color liquid crystal display can display a variety of information with a small amount of power consumption.

[0023] The display unit 20 displays the level Y of the contained items 72 measured by the sensor unit 16. In Figs. 1 and 3, a bar display 22 whose length expands or contracts according to the value of the level Y is displayed on the display unit 20. The display unit 20 also displays a color gauge 24 (one example of a gauge) that is colored in multiple colors. The length direction of the color gauge 24 is arranged along the expansion and contraction direction of the bar display 22. The color gauge 24 includes multiple sections (three in Fig. 1) that are arranged along the expansion and contraction direction of the bar display 22. The sections of the color gauge 24 correspond to multiple level ranges set for the level Y of the contained items 72, and the level ranges are defined by multiple level setting values ​​(e.g., threshold values) set for the level Y.

[0024] Display unit 20 displays the relative position of level Y with respect to container 70 that contains contents 72, together with bar display 22. Specifically, the length of bar display 22 expands or contracts according to the value of level Y of contents 72 within container icon 25 that resembles container 70. The length of bar display 22 with respect to the size of container icon 25 corresponds to the relative position of level Y of contents 72 with respect to the entire container 70.

[0025] A bar arrow 22a is displayed at the tip (top end) of the extension / contraction direction of the bar display 22. The bar arrow 22a indicates a position within the color gauge 24 that corresponds to the length of the bar display 22. The color gauge 24 indicates to which level range the measured level Y belongs, among a plurality of level ranges defined by level setting values.

[0026] The color gauge 24 includes a plurality of sections. The plurality of sections of the color gauge 24 are divided into a plurality of level ranges. The plurality of sections of the color gauge 24 are arranged along the direction of increase and decrease of the level Y on the display unit 20. The container icon 25 and the bar display 22 are displayed next to the color gauge 24 (alongside the color gauge 24). Since the color gauge 24 is displayed along with the container icon 25 and the bar display 22 on the display unit 20, the relative position of the level setting value with respect to the container 70 is displayed together with the bar display 22.

[0027] The display unit 20 also displays an auxiliary display unit 26 that shows information other than the bar display 22 and the color gauge 24. In Fig. 1, the measured level Y is displayed in the auxiliary display unit 26 as a percentage value (percentage of the full value, displayed as %).

[0028] The display unit 20 also displays an output status display section 27. The output status display section 27 displays the status of a signal line whose output changes depending on the relationship between the measured level Y and the level setting value. For example, if a signal is sent from a specific signal line when the level Y exceeds a threshold value set as the level setting value, a number corresponding to that signal line is displayed on the output status display section 27. For example, in FIG. 1, the bar arrow 22a indicates the topmost section of the three sections of the color gauge 24. This state of the display unit 20 indicates that two threshold values ​​are set as the level setting value and that the measured level Y exceeds both of the two threshold values.

[0029] If a signal line is provided that outputs a signal when the measured level Y exceeds a threshold value, a signal is output from each of the two signal lines corresponding to the two threshold values ​​in the state shown in Fig. 1. In order to indicate that signals are being output from two signal lines in Fig. 1, numbers corresponding to the two signal lines that are outputting signals (here, "1" and "2") are displayed in output status display section 27.

[0030] In addition, an operation unit 30 is also arranged on the same outer surface of the terminal unit 21 as the display unit 20. The operation unit 30 in FIG. 1 is arranged below the display unit 20. The operation unit 30 includes a menu key 32 and a directional key 33. The directional key 33 has an up key 36 (up key) and a down key 35 (down key) arranged along the longitudinal direction A. The directional key 33 also has a left key 38 (left key) and a right key 37 (right key) arranged in a direction intersecting the longitudinal direction A. Furthermore, a center key 39 (center key) is provided in the directional key 33 at a position surrounded by the up key 36, down key 35, left key 38, and right key 37.

[0031] Although the details will be described later, the user of the level meter 10 can change the operating parameters of the level meter 10 by operating the operation unit 30. In particular, the user can change the display content of the display unit 20 and the level setting value related to the level range by operating the operation unit 30. The user can also change the display format of the level Y displayed on the auxiliary display unit 26 by changing the display content of the display unit 20. For example, the user can change the level Y displayed as a percentage in FIG. 1 to be displayed as a length value (for example, mm: millimeter value). For example, the display format of the level Y may be switched every time the user operates the left key 38 or the right key 37.

[0032] A connection part 12 is provided on the rear surface of the terminal part 21 (the part opposite to the display part 20). As shown in Figs. 1 and 2, the connection part 12 is cylindrical and protrudes from the rear surface of the terminal part 21. The outer peripheral surface of the cylindrical connection part 12 is a connection screw part 14 with threads. As shown in Fig. 2, an external input terminal 12C and an external output terminal 12D are included inside the connection part 12. The external input terminal 12C is a terminal for inputting a signal or power, or both, from the outside to the level meter 10. The external output terminal 12D is a terminal for outputting a signal from the level meter 10 to the outside. The external input terminal 12C and the external output terminal 12D may each include multiple signal lines or multiple terminals. For example, a signal may be output to the outside from different signal lines or different output terminals depending on the level range to which the measured level Y belongs.

[0033] A connection cable 92 shown in Fig. 3 is connected to the connection unit 12. The connection cable 92 connects the level meter 10 to a management device 90 (such as a programmable controller) provided outside the container 70. A signal indicating the level Y of the contained item 72 measured by the level meter 10 is transmitted (output) to the management device 90 via an external output terminal 12D (part of an output unit 66 described below) of the connection unit 12 and the connection cable 92. The management device 90 manages the operation of the entire facility including the container 70 based on the signal received from the level meter 10.

[0034] As shown in FIG. 1, an indicator light 52 is provided on the outer peripheral surface of the base unit 15a connected to the lower side of the terminal unit 21. The indicator light 52 changes its lighting state according to the measured level Y of the contained contents 72. The user can roughly know the state of the contained contents 72 by visually checking the lighting state of the indicator light 52. In FIG. 1, the indicator light 52 is disposed between the terminal unit 21 and the sensor unit 16. The indicator light 52 can emit light in various lighting colors (e.g., green, yellow, red, etc.). It is preferable that the indicator light 52 emits light in a lighting color corresponding to the level range to which the level Y measured by the level meter 10 belongs. For example, it is preferable that the indicator light 52 emits light in the same color as the color of the section indicated by the bar arrow 22a in the color gauge 24, which is color-coded by a plurality of colors for each section.

[0035] 2, a sensor IC 41 (IC: Integrated Circuit) and a sensor board 42 supporting the sensor IC 41 are disposed inside the sensor unit 16 below the base 15a. The sensor IC 41 transmits and receives radio waves and processes signals to measure the level Y of the contained item 72. The signal processed by the sensor IC 41 is transmitted to a display board 60 provided in the terminal unit 21.

[0036] For example, a monolithic microwave integrated circuit (MMIC) is used as the sensor IC 41. The MMIC is an IC in which a plurality of semiconductor components that transmit and receive radio waves, and perform signal processing based on the transmitted and received radio waves are integrated into a single semiconductor device (one chip). In the sensor IC 41 in FIG. 2, an antenna is integrated into the MMIC using antenna in package (AiP) technology or antenna on package (AoP) technology. That is, in FIG. 2, the sensor IC 41 is an antenna-integrated package (antenna on package) in which a transmitting circuit 43T that transmits radio waves and a receiving circuit 43R that receives radio waves are integrated into a single semiconductor device. By using an antenna-integrated MMIC as the sensor IC 41, the volume occupied by the configuration for transmitting and receiving radio waves is reduced, and the overall dimensions of the level meter 10 are made compact. The sensor IC 41 is not limited to a single antenna-integrated MMIC, and may include a plurality of ICs. The sensor IC 41 may include, for example, an MMIC and a microcomputer. The antenna-integrated MMIC may include a radio wave transmitting antenna, a radio wave receiving antenna, and a circuit that controls the transmission and reception of radio waves, and the microcomputer may include a circuit that performs signal processing and arithmetic processing based on a signal received from the antenna-integrated MMIC.

[0037] The sensor IC 41 is mounted on the lower surface of the sensor board 42. The sensor board 42 is an electronic circuit board in which various electronic circuit elements are arranged on a plate made of an insulator such as glass or resin. In Fig. 2, the sensor board 42 is arranged so as to be oriented perpendicular to the longitudinal direction A (horizontal direction in Fig. 2).

[0038] The measurement end 40 is located below the sensor substrate 42. The measurement end 40 in FIG. 2 includes, as an internal structure, a waveguide 45, a horn antenna 46, and a dielectric lens 48. When the sensor IC 41 is an antenna-integrated MMIC, a radio wave serving as a measurement signal Tx is transmitted from a transmission circuit 43T of the sensor IC 41. The measurement signal Tx transmitted from the sensor IC 41 is guided toward the contained object 72 through the waveguide 45, the horn antenna 46, and the dielectric lens 48 in this order. The reflected signal Rx reflected by the contained object 72 and incident on the measurement end 40 is guided toward the receiving circuit 43R of the sensor IC 41 through the dielectric lens 48, the horn antenna 46, and the waveguide 45 in this order.

[0039] The waveguide 45, the horn antenna 46, and the dielectric lens 48 arranged inside the sensor unit 16 guide radio waves in the longitudinal direction A by their respective directivities for radio waves, and when combined, they show strong directivity for radio waves as a whole. Therefore, even if the sensor unit 16 has a small longitudinal dimension (length along the longitudinal direction A), it can properly guide the measurement signal Tx and the reflected signal Rx. Furthermore, because the measurement signal Tx and the reflected signal Rx are properly guided, the measurement signal Tx can be transmitted and the reflected signal Rx can be received by the common measurement end 40, even if the position of the transmitting circuit 43T and the position of the receiving circuit 43R are different in the sensor IC 41. Therefore, by using the waveguide 45, the horn antenna 46, and the dielectric lens 48, the designer of the level meter 10 can reduce the longitudinal dimension of the level meter 10 including the sensor unit 16, and the overall dimension of the level meter 10 can be made compact.

[0040] On the other hand, a rotation mechanism 19 is provided inside the base portion 15a arranged above the sensor portion 16. The rotation mechanism 19 in FIG. 2 is arranged at the lower end (one end in the longitudinal direction A) of the housing 15, that is, between the housing 15 and the sensor portion 16. The rotation mechanism 19 can rotate the base portion 15a and the terminal portion 21 connected to the base portion 15a relative to the sensor portion 16. The rotation mechanism 19 is arranged so that the rotation axis is parallel to the longitudinal direction A. By providing the rotation mechanism 19, the user can rotate the housing 15 to orient the display portion 20 in a direction that is easy to view. In particular, when the level gauge 10 is attached to a container 70 (such as a tank) containing the contents 72 by the mounting screw portion 18, the user can orient the display portion 20 in a direction that is easy to view without moving the entire level gauge 10.

[0041] A display board 60 is disposed inside the terminal unit 21. The display board 60 is an electronic circuit board in which various electronic circuit elements are disposed on a plate made of an insulating material such as glass or resin. A signal processing circuit for controlling the display unit 20 is mounted on the display board 60. The display board 60 receives a signal from the sensor IC 41 and converts the level Y of the contained item 72 measured by the sensor unit 16 into a signal for display on the display unit 20. The display board 60 in FIG. 2 is disposed on the back side of the display unit 20 (inside the housing 15 in FIG. 2).

[0042] 2 includes a display device 28 and a transparent display window 29. The display device 28 is, for example, an LCD, particularly an LCD capable of color display. The display window 29 is a plate made of an optically transparent material such as glass, acrylic, polyarylate, or polycarbonate, and optically transmits the display content of the display device 28 to the outside of the housing 15.

[0043] The indicator lamp 52 arranged between the terminal unit 21 and the sensor unit 16 includes a plurality of status LEDs 50 (LEDs: Light Emitting Diodes) and a transmission window 53. The plurality of status LEDs 50 are arranged on the upper side of the sensor board 42, that is, on the surface opposite to the sensor IC 41. The transmission window 53 of the indicator lamp 52 is arranged on the outer peripheral surface above the status LEDs 50. The transmission window 53 arranged on the outer peripheral surface of the base portion 15a has a surface along the longitudinal direction A (vertical surface) facing the outside of the housing 15. The light emitted from the status LEDs 50 is guided to the outside of the housing 15 through the transmission window 53 including a member that diffuses the light. Here, the member that diffuses the light included in the transmission window 53 is preferably a doughnut-shaped disk. In addition, it is preferable that a tapered surface 53a having a tapered shape is formed on the inner peripheral surface of the doughnut-shaped member that diffuses the light. When the tapered surface 53a is formed on the inner periphery side of the transmission window 53, the light emitted from the status LED 50 is reflected by the tapered surface 53a and is guided to the outside of the housing 15 reliably.

[0044] The lighting state of the status LED 50 changes according to the level Y of the contained contents 72 measured by the sensor unit 16. The light emitted from the status LED 50 is guided to the outside of the housing 15 through the transparent window 53. Therefore, as the lighting state of the status LED 50 changes according to the level Y of the contained contents 72, the lighting state of the indicator light 52 changes. In addition, since the transparent window 53 contains a material that diffuses light, the light emitted from the status LED 50 is diffused in a direction intersecting with the longitudinal direction A. Therefore, the user can easily visually grasp the lighting state of the indicator light 52 from a long distance.

[0045] The status LED 50 may emit light in a single color (e.g., red, yellow, green, etc.) or may emit light by switching between multiple colors (e.g., red, yellow, green, etc.). When the status LED 50 emits light by switching between multiple colors, multiple light-emitting elements that emit light in different colors may be included in one LED, or a combination of multiple LEDs that emit light in different colors may be arranged as the status LED 50. The status LED 50 may emit light by mixing multiple colors. When the status LED 50 emits light by switching between multiple colors, the status LED 50 may emit light in a color corresponding to the color of the section of the color gauge 24 that corresponds to the level range to which the measured level Y belongs.

[0046] Next, the relationship between the components of the level meter 10 will be described with reference to FIG. 4. FIG. 4 is a block diagram that shows an example of the relationship between the components of the level meter 10. As shown in FIG. 4, the sensor IC 41 of the sensor unit 16 includes a transmitting / receiving unit 43, a radar control unit 44, and a processing unit 62. The transmitting / receiving unit 43 has a transmitting circuit 43T that transmits a measurement signal Tx and a receiving circuit 43R that receives a reflected signal Rx. The sensor IC 41 may include multiple ICs. For example, the sensor IC 41 may include an antenna-integrated MMIC and a microcomputer.

[0047] The radar control unit 44 has a transmission control unit 80 that determines the waveform of the measurement signal Tx, a radar transmission and reception circuit 81 that performs mutual conversion between digital signals and radio waves, and a signal processing unit 89 that performs signal processing based on the measurement signal Tx and the reflected signal Rx. When the sensor IC 41 includes an antenna-integrated MMIC and a microcomputer, the antenna-integrated MMIC may have the parts of the radar control unit 44 excluding the signal processing unit 89 (the transmission control unit 80 and the radar transmission and reception circuit 81) and the transceiver unit 43, and the microcomputer may be configured to have the signal processing unit 89 and the processing unit 62.

[0048] The processing unit 62 includes a storage unit 63 and a calculation unit 64. The storage unit 63 stores various set values ​​(data) related to the operation of the level meter 10. The calculation unit 64 performs various calculations related to the operation of the level meter 10 based on the set values ​​stored in the storage unit 63 and the signal processing results of the signal processing unit 89. The storage unit 63 includes a storage device such as a RAM (Random Access Memory) and a ROM (Read Only Memory). The calculation unit 64 includes a processor such as a CPU (Central Processing Unit). The storage unit 63 and the calculation unit 64 may be provided on the display board 60 of the housing 15. Alternatively, the sensor unit 16 and the housing 15 may be provided with separate storage units 63 and calculation units 64, respectively, and the stored data and the calculation processing in charge may be shared between the sensor unit 16 and the housing 15. As shown in FIG. 4, the calculation unit 64 and the radar transmission / reception circuit 81 and the signal processing unit 89 of the radar control unit 44 function together as a level determination unit 88. The level determining unit 88 performs a process of determining the level Y based on the reflected signal Rx received by the receiving circuit 43R and container information related to the container 70 (eg, the height of the container 70, etc.).

[0049] On the other hand, the display board 60 of the terminal unit 21 has a setting unit 61, an input unit 65, and an output unit 66. The setting unit 61 performs a process of sequentially setting container information related to the container 70 and a plurality of level setting values ​​related to the level Y. The input unit 65 is an interface circuit that inputs an input provided from outside the level meter 10 as a signal to the level meter 10. The input provided from outside the level meter 10 is, for example, a user's operation on the operation unit 30, and a control signal provided from an external device (such as the management device 90) via the external input terminal 12C. The input unit 65 stores, for example, flag information indicating that the operation unit 30 has been operated, and data such as a setting value provided via the external input terminal 12C in the storage unit 63.

[0050] The output unit 66 is an interface circuit that outputs to the outside a signal generated inside the level meter 10. For example, the output unit 66 changes the display content of the display unit 20 and the lighting state of the indicator lamp 52 according to the calculation result (such as the value of the level Y) by the calculation unit 64. The output unit 66 also transmits the calculation result by the calculation unit 64 to an external device via the external output terminal 12D.

[0051] Measurement of the level Y by the level meter 10 will be described in more detail with reference to Fig. 5 and Fig. 6. Fig. 5 is a diagram showing an example of the configuration of the radar transmission / reception circuit 81 and the transmission / reception unit 43 included in the sensor IC 41. Fig. 6 is a diagram showing the relationship between the measurement signal Tx and the reflected signal Rx.

[0052] As shown in FIG. 5, the radar transmission / reception circuit 81 includes a ramp generator 82, a power amplifier 83, a low-noise amplifier 84, a mixer 85, a low-pass filter 86, and an analog-to-digital converter 87.

[0053] The level meter 10 of this embodiment measures the level Y by a radar method using FMCW. The ramp generator 82 is connected to the transmission control unit 80. When the ramp generator 82 receives data indicating the waveform of the measurement signal Tx determined by the transmission control unit 80, it generates a signal having a waveform according to the data. In this embodiment, a waveform that repeatedly increases and decreases in frequency is used as the waveform of the measurement signal Tx.

[0054] FIG. 6 shows a graph showing the change in frequency of the measurement signal Tx (and the reflected signal Rx) over time. In FIG. 6, the frequency of the measurement signal Tx increases linearly from the minimum value (Min) as time passes, and when it reaches the maximum value (Max), it returns to the minimum value again. In this way, the frequency of the measurement signal Tx repeatedly increases and decreases. Note that the frequency increase / decrease pattern is not limited to this, and it is sufficient that the level determination unit 88 can calculate the level Y based on the comparison between the measurement signal Tx and the reflected signal Rx. For example, a pattern may be used in which the frequency decreases linearly from the maximum value as time passes, and when it reaches the minimum, it returns to the maximum value again. Also, a pattern in which the frequency increases and decreases linearly between the maximum value and the minimum value may be used. The measurement signal Tx used in this embodiment is a radio wave in the 60 GHz band, and the minimum value of the frequency is, for example, 58 GHz, and the maximum value is, for example, 69 GHz. Note that the frequency band used is not limited to this, and a frequency of, for example, 77 GHz-81 GHz may be used.

[0055] The signal generated by the ramp wave generator 82 in Fig. 5 is amplified by a power amplifier 83 and sent to the transmission circuit 43T. The transmission circuit 43T generates radio waves with a waveform corresponding to the sent signal and transmits the radio waves as a measurement signal Tx to the contained item 72. The measurement signal Tx is reflected by the interface 74 of the contained item 72 to become a reflected signal Rx, which is received as a received signal by the receiving circuit 43R. The reflected signal Rx becomes a wave out of phase with the measurement signal Tx.

[0056] As shown by the dashed line in Fig. 6, the reflected signal Rx is a wave that is shifted from the measurement signal Tx by a time difference Δt. This time difference Δt is a value that corresponds to the distance YA (Fig. 3) from the measurement end 40 to the interface 74 of the contents 72. Because the reflected signal Rx travels back and forth between the measurement end 40 and the contents 72, there is a relationship of Δt = 2 × YA / c, where c is the speed of light.

[0057] Then, a frequency difference ΔF occurs between the measurement signal Tx and the reflected signal Rx according to the magnitude of the time difference Δt. There is a certain relationship between the frequency difference ΔF and the time difference Δt that depends on the waveform of the measurement signal Tx. The waveform of the measurement signal Tx is a waveform in which the frequency changes linearly with the passage of time. In other words, there is a certain relationship between the frequency difference ΔF and the time difference Δt that depends on the frequency change per unit time in the waveform of the measurement signal Tx. For example, the frequency of the measurement signal Tx increases linearly from the minimum value (Min) as time passes, and reaches the maximum value (Max). In this case, the relationship between the frequency difference ΔF and the time difference Δt is uniquely determined by the difference between the maximum and minimum values ​​of the frequency of the measurement signal Tx, which is the bandwidth of the frequency modulation, and the relationship of the frequency change with the passage of time. Therefore, the level meter 10 can calculate the time difference Δt based on the frequency difference ΔF, which is the difference between the measurement signal Tx and the reflected signal Rx. Then, the level meter 10 can calculate the distance YA (Δt×c / 2) from the time difference Δt. Furthermore, the level meter 10 can calculate the value of the level Y based on the distance YA. Specifically, the difference between the height of the container 70 (the distance from the bottom of the container 70 to the top surface inside the container 70) and the distance YA is the value of the level Y. Therefore, the level determination unit 88 can determine the level Y of the contents 72 based on the reflected signal Rx received by the receiving circuit 43R and container information about the container 70 (such as the height of the container 70). Note that, as will be described in detail later, the container information about the container 70, such as the height of the container 70, the bottom distance Y0 from the level meter 10 to the bottom of the container 70, and the top distance Y1 from the level meter to the top surface inside the container 70 (the thickness of the top plate of the container 70 in FIG. 3), may be set in advance by the setting unit 61 before the measurement of the level Y is started. Note that the distance from the level meter 10 is, more precisely, the distance from the measurement reference plane XS (a plane on which the distance value is treated as zero) that is the measurement reference in the level meter 10. The position of the measurement reference plane XS is determined in advance before the level meter 10 is used (for example, when the level meter 10 is designed). For example, the position where the level gauge 10 is attached to the container 70 (the position of the outer upper surface of the container 70 in FIG. 3) is determined as the measurement reference surface XS. In terms of the position inside the level gauge 10, the lower surface of the mounting part 17 (the upper end of the mounting screw part 18) becomes the measurement reference surface XS.In addition, since there is a certain relationship between the frequency difference ΔF and the time difference Δt that depends on the waveform of the measurement signal Tx, the correspondence relationship between the frequency difference ΔF and the distance YA can be obtained in advance. The correspondence relationship between the frequency difference ΔF and the distance YA may be stored in the storage unit 63 in advance.

[0058] 5, a received signal corresponding to the reflected signal Rx received by the receiving circuit 43R is input to a mixer 85 via a low-noise amplifier 84. A signal corresponding to the waveform of the measurement signal Tx output from the ramp generator 82 is also input to the mixer 85, and the mixer 85 generates a mixed signal Mx by mixing the waveforms of the measurement signal Tx and the reflected signal Rx. The mixer 85 included in the radar transmitting and receiving circuit 81 functioning as a part of the level determining unit 88 specifically mixes the measurement signal Tx and the reflected signal Rx to generate an IF signal (IF: Intermediate Frequency) as the mixed signal Mx.

[0059] The IF signal (intermediate frequency signal) has a waveform that includes high frequency components originating from the 60 GHz band frequencies of the measurement signal Tx and the reflected signal Rx, and low frequency components corresponding to the frequency difference ΔF between the measurement signal Tx and the reflected signal Rx. The IF signal is input to a low-pass filter 86, which extracts a low frequency waveform corresponding to the frequency difference ΔF. The extracted low frequency waveform is input to an analog-to-digital converter 87. The analog-to-digital converter 87 converts the low frequency waveform into a digital value and outputs it to a signal processing unit 89.

[0060] A signal processing unit 89, which functions as part of the level determination unit 88, converts the low-frequency waveform output from the analog-digital converter 87 into a frequency signal Px by fast Fourier transform processing or the like. The frequency signal Px is a signal that indicates the wave strength for each frequency, and the frequency corresponding to the maximum peak PS of this frequency signal Px is the frequency difference ΔF between the measurement signal Tx and the reflected signal Rx. The signal processing unit 89 transmits the frequency signal Px to the calculation unit 64 in FIG. 4.

[0061] The calculation unit 64, which functions as a part of the level determination unit 88, calculates the values ​​of the distance YA and the level Y based on the frequency signal Px. When calculating the values ​​of the distance YA and the level Y, the calculation unit 64 refers to information stored in the storage unit 63. For example, the storage unit 63 stores the correspondence between the frequency difference ΔF and the distance YA, values ​​for calculating the level Y from the distance YA (container information such as the height of the container 70), and the like.

[0062] Depending on the measurement environment, a peak other than the maximum peak PS may appear in the frequency signal Px due to an element other than the interface 74 of the contents 72 (for example, equipment such as a stirrer provided in the container 70). Even if multiple peaks exist in the frequency signal Px, the calculation unit 64 can identify only the maximum peak PS originating from the contents 72 by performing appropriate calculations. For example, data on the frequency signal Px obtained in a state where there is no contents 72 (a state where the container 70 is empty) may be stored in advance in the storage unit 63. The calculation unit 64 can identify the maximum peak PS originating from the contents 72 by examining the difference between the frequency signal Px obtained in a state where there is no contents 72 and the frequency signal Px obtained in a state where there is the contents 72.

[0063] After calculating the frequency difference ΔF corresponding to the maximum peak PS of the frequency signal Px, the calculation unit 64 calculates the distance YA and the value of the level Y based on the frequency difference ΔF and the information stored in the storage unit 63. In this way, the calculation unit 64, which functions as a part of the level determination unit 88, determines the level Y of the contained item 72 based on the intermediate frequency signal. The calculation unit 64 transmits the calculated value of the level Y to the output unit 66. The output unit 66 changes the display content of the display unit 20 and the lighting state of the indicator lamp 52 according to the value of the level Y. The value of the level Y is also sent to the management device 90 (FIG. 3) through the external output terminal 12D. The output unit 66 may output a binary or multi-value control signal based on the result of comparing the calculated value of the level Y with a threshold value to the management device 90 through the external output terminal 12D. Also, instead of the value of the level Y itself, a signal indicating that a specific control should be executed according to the state of the level Y may be sent to the management device 90. For example, when level Y rises above or falls below a particular threshold a signal may be sent to management device 90 indicating that operation of pumps, valves, etc. should be altered.

[0064] Next, the state transition of the level meter 10 will be described with reference to FIG. 7. First, when the level meter 10 is started, the initial setting 100 is started. Although details will be described later, in the initial setting 100, various setting screens for sequentially setting container information, level setting values, etc. are sequentially displayed on the display unit 20. Note that in the initial setting 100, the operating conditions of the level meter 10, such as whether the level meter 10 outputs an analog signal for a measured value or serially communicates with an external device, may be set. On the other hand, there may be an operating condition that is not displayed in the initial setting 100 and is not set by the user. For example, an operating condition that one of the terminals included in the external output terminal 12D outputs an analog value may be predetermined regardless of a user's operation. In addition, an operating condition that communication with an external device automatically occurs depending on the external device connected to the level meter 10 may be predetermined. For example, when the level meter 10 is connected to a device (master device) that manages the level meter 10, communication between the level meter 10 and the master device may be automatically performed by IO-Link communication specified in IEC61131-9 (IEC: International Electrotechnical Commission).

[0065] Once the initial setting 100 is complete, the level meter 10 enters the measurement mode 500. In the measurement mode 500, the level meter 10 measures the level Y of the contained content 72. In the measurement mode 500, the relative position of the level setting value with respect to the container 70 is displayed on the display unit 20 together with the bar display 22, as shown in FIG.

[0066] In the measurement mode 500, the display unit 20 can display a menu screen 600. The display screen of the measurement mode 500, which displays the bar display 22 and the like, and the menu screen 600 can transition back and forth. For example, each time the user operates the menu key 32 in the measurement mode 500, the display content of the display unit 20 may be switched between the display screen of the measurement mode 500 and the menu screen 600.

[0067] A menu screen 600 displays a plurality of options corresponding to individual setting contents. In response to a user's selection, the display content of the display unit 20 transitions from the menu screen 600 to an individual setting screen such as a container setting screen 610, a setting value change screen 620, or a various setting screen 630. The menu screen 600 and the individual setting screens can transition to each other. For example, when the left key 38 is operated on an individual setting screen, the display unit 20 may be configured to return to the menu screen 600.

[0068] Next, with reference to FIG. 8, screen transitions of the display unit 20 in the initial setting 100 will be described. In the initial setting 100, a plurality of setting screens for sequentially setting container information related to the container 70 and a plurality of level setting values ​​related to the level Y are displayed one by one. In each setting screen, the container information, the level setting value of the level Y, and the like are sequentially set by the setting unit 61. Specifically, the setting unit 61 sequentially displays setting screens for setting the container information, the level setting value of the level Y, and the like on the display unit 20, and stores the setting contents selected by the user in each setting screen in the storage unit 63, thereby sequentially setting the container information, the level setting value, and the like. Note that it is preferable that the process of actually storing the setting contents selected by the user in the initial setting 100 in the storage unit 63 is performed after all the settings in the initial setting 100 are completed (after a setup completion confirmation screen 390 described later). In other words, it is preferable that the setting unit 61 temporarily holds the contents set by the user in each setting screen included in the initial setting 100, and after the initial setting 100 is completed, the held contents are collectively stored in the storage unit 63. Details of the display contents of each setting screen will be described later.

[0069] When the initial setting 100 starts, a language setting screen 110 is first displayed on the display unit 20. On the language setting screen 110, the language (English, Japanese, etc.) to be used for display on the display unit 20 is selected by the user.

[0070] When the language setting is completed, a setup start confirmation screen 120 is displayed on the display unit 20 to confirm with the user whether or not to start the setup of the level meter 10 (initial settings of various setting values). In this setup start confirmation screen 120, the display unit 20 can return to the language setting screen 110 in response to a user operation (e.g., operation of the left key 38). Thereafter, in the same manner with other setting screens, the display unit 20 can return from each individual setting screen to the previous screen until the initial setting 100 is completed.

[0071] If the user selects not to start setup yet on the setup start confirmation screen 120, the display unit 20 displays the distance measurement value confirmation screen 130. On the distance measurement value confirmation screen 130, the distance calculated by the level meter 10 from the measurement signal Tx and the reflection signal Rx is displayed on the display unit 20. The distance displayed on the distance measurement value confirmation screen 130 is the distance from the measurement reference surface XS of the level meter 10 to the object that reflects the measurement signal Tx. This distance is a value that can be measured by the level meter 10 even if the level meter 10 is not attached to the container 70 or even if the container information has not been set. By checking the distance displayed on the distance measurement value confirmation screen 130, the user can determine whether the level meter 10 is correctly attached to the container 70 that contains the contents 72 to be measured. For example, if the displayed distance is outside the range assumed as the distance from the level meter 10 to the contents 72 or if the displayed distance is unstable, the level meter 10 may not be correctly attached to the container 70. If the user determines on the distance measurement confirmation screen 130 that the level meter 10 is correctly attached to the container 70, the user may return to the setup start confirmation screen 120 and start the setup.

[0072] When the user selects to start the setup on the setup start confirmation screen 120, the display unit 20 displays the input / output setting screen 140. A plurality of options are displayed on the input / output setting screen 140. In response to the user's selection, the display unit 20 transitions from the input / output setting screen 140 to individual setting screens such as a PNP / NPN setting screen 141, a control output number setting screen 142, and an external input setting screen 143. The user can also skip the settings on the PNP / NPN setting screen 141, the control output number setting screen 142, and the external input setting screen 143. Initial setting values ​​are set in advance for the contents set on the PNP / NPN setting screen 141, the control output number setting screen 142, and the external input setting screen 143, and when the user skips the settings, the initial setting values ​​are used. Initial setting values ​​may also be set in advance for the setting items set on other setting screens.

[0073] In the PNP / NPN setting screen 141, the characteristics of the transistors (PNP type transistor or NPN type transistor) used for the external output and external input of the level meter 10 are set. The characteristics of the connection unit 12 are determined according to the selection in this PNP / NPN setting screen 141. For example, which terminals among the multiple terminals included in the connection unit 12 become the external input terminal 12C and the external output terminal 12D is determined. Alternatively, it is determined whether the signal output from the external output terminal 12D becomes a high voltage (high level, for example, 5V) or a low voltage (low level, for example, 0V) when the conditions set by the user are satisfied. In the PNP / NPN setting screen 141, the display unit 20 may display options of, for example, "PNP" and "NPN" and allow the user to select one of the options. For example, if the terminals included in the connection unit 12 include one analog output terminal that outputs an analog value, four digital output terminals that output digital signals, and one input / output terminal that can be switched between input and output, the PNP / NPN setting screen 141 can be used to set the output voltage of the digital output terminal and to switch between input / output of the input / output terminal.

[0074] The number of control signals output from the level meter 10 is set on the control output number setting screen 142. For example, when there are multiple terminals (signal lines) as the external output terminals 12D, how many external output terminals 12D are to be used in the current measurement is set. The number of control signals set on the control output number setting screen 142 corresponds to the number of thresholds of the level Y to be set later. Each external output terminal 12D corresponds to a threshold set by the user, and when the measured level Y crosses the threshold (when it exceeds or falls below), a signal is output from the external output terminal 12D corresponding to the threshold. On the control output number setting screen 142, the display unit 20 may display, for example, multiple options (e.g., options of 0, 1, 2, 3, 4, and 5) indicating the number of control signals, and allow the user to select one of the options.

[0075] In the external input setting screen 143, it is set whether or not to enable the external input. When the external input is enabled in this external input setting screen 143, one of the terminals included in the connection unit 12 functions as the external input terminal 12C. In the external input setting screen 143, the display unit 20 may display options of, for example, "OFF" (disabled) and "ON" (enabled), and allow the user to select one of the options.

[0076] When the settings on the input / output setting screen 140 are completed, the display unit 20 transitions to a distance unit setting screen 150. On the distance unit setting screen 150, the distance unit for expressing the measurement value of the level meter 10 is set.

[0077] When the setting on the distance unit setting screen 150 is completed, the display unit 20 transitions to a scaling confirmation screen 160. On the scaling confirmation screen 160, it is selected whether or not to execute the scaling setting 200. In the scaling setting 200, the display value is scaled. In the scaling of the display value, for example, container information and a level setting value are set for converting the measurement value (measured in distance units) by the level meter 10 into a numerical value for display (for example, a display value in capacity units) or into a numerical value to be output to the outside. The scaling setting 200 includes a plurality of setting screens.

[0078] If the user selects to execute the scaling setting 200 on the scaling confirmation screen 160, the display unit 20 transitions to a setting screen for the scaling setting 200. If the user selects not to execute the scaling setting 200, the display unit 20 transitions to a setting screen for the operation setting 300. In the operation setting 300, container information and a level setting value used by the level meter 10 to measure the level Y, etc. are set. The operation setting 300 includes a plurality of setting screens.

[0079] 9, a screen transition of the display unit 20 in the operation setting 300 will be described. When the operation setting 300 is started, the setting unit 61 first performs the container setting 210. In the container setting 210, the setting of container information related to the container 70 is performed.

[0080] In the container setting 210, the setting unit 61 first displays a bottom distance setting screen 211 on the display unit 20. In the bottom distance setting screen 211, the setting unit 61 allows the user to set the distance from the measurement reference surface XS of the level meter 10 to the bottom of the container 70 (bottom distance Y0).

[0081] Next, the setting unit 61 causes the display unit 20 to display an upper surface distance setting screen 212. On the upper surface distance setting screen 212, the setting unit 61 causes the user to set an upper surface distance Y1 from the measurement reference surface XS of the level gauge 10 to the upper surface inside the container 70.

[0082] When the container setting 210 is completed, the setting unit 61 sequentially displays a setting screen for setting a next level setting value. In Fig. 9, after the container setting 210, the setting unit 61 causes the display unit 20 to display a first threshold setting screen 310.

[0083] Incidentally, the scaling setting 200 includes a setting item corresponding to the container setting 210. When the scaling setting 200 is performed, the screen transition of the display unit 20 merges with the operation setting 300 after the scaling setting 200 is completed. Specifically, after the scaling setting 200 is completed, a first threshold setting screen 310 is displayed on the display unit 20.

[0084] In the first threshold setting screen 310, the setting unit 61 allows the user to set a first threshold as one of the level setting values ​​related to the level Y. The first threshold is one of the thresholds related to the level Y measured by the level meter 10. When the level Y crosses over (exceeds or falls below) the first threshold, the operation of the level meter 10 (for example, the lighting color of the indicator lamp 52, the signal output state of the external output terminal 12D, etc.) changes.

[0085] The first threshold setting screen 310 can be switched to and from an output logic setting screen 315 related to the first threshold. In the output logic setting screen 315, it is set how the operation of the level meter 10 changes when the level Y measured by the level meter 10 changes with respect to the threshold (when it exceeds or falls below). Specifically, it is set whether the characteristic of the external output terminal 12D corresponding to the first threshold is normally open or normally closed. When normally open is selected, when the level Y exceeds the first threshold, the operation of the level meter 10 changes (for example, the signal of the corresponding external output terminal 12D becomes valid). When normally closed is selected, when the level Y falls below the first threshold, the operation of the level meter 10 changes.

[0086] When the setting on the first threshold setting screen 310 is completed, the setting unit 61 then transitions the display on the display unit 20 to a second threshold setting screen 320. On the second threshold setting screen 320, the setting unit 61 allows the user to set the second threshold in the same manner as the setting of the first threshold on the first threshold setting screen 310. In addition, the second threshold setting screen 320 can transition to and from an output logic setting screen 325 related to the second threshold.

[0087] Such threshold setting is repeated for the number of control signals set on the control output number setting screen 142. Here, a combination of a numerical value setting and an output logic setting is performed for each threshold in sequence, but after only the numerical values ​​of all thresholds are set in sequence, the output logic of all thresholds may be set in sequence. For example, the first threshold setting screen 310 and the second threshold setting screen 320 may be displayed in this order, and then the output logic setting screen 315 for the first threshold and the output logic setting screen 325 for the second threshold may be displayed in this order. When the number of control signals is 1, only the first threshold is set. When the number of control signals is 0, the threshold setting is skipped.

[0088] When all threshold settings and output logic settings are completed, the display on the display unit 20 transitions to an indicator light pattern setting screen 380. In the indicator light pattern setting screen 380, it is set how the indicator light 52 is turned on according to the relative relationship between the measured level Y and the threshold value (level setting value). The settings on this indicator light pattern setting screen 380 include a setting of the lighting color of the indicator light 52 corresponding to the level range to which the measured level Y belongs. Also, according to the lighting color of the indicator light 52 set on the indicator light pattern setting screen 380, it is also determined how each section of the color gauge 24 is color-coded.

[0089] When the settings on the indicator light pattern setting screen 380 are completed, the display on the display unit 20 transitions to a setup completion confirmation screen 390 for confirming with the user whether or not to complete the setup (initial settings). When the user determines to complete the setup on the setup completion confirmation screen 390, the initial settings 100 including the operation settings 300 are completed, and the level meter 10 transitions to the measurement mode 500 in Fig. 7. If the user does not yet complete the setup, the user can sequentially return the display on the display unit 20 to a screen prior to the setup completion confirmation screen 390 (such as the indicator light pattern setting screen 380 or the second threshold setting screen 320) and redo the various settings in the initial settings 100.

[0090] Next, screen transitions on the display unit 20 during the scaling setting 200 will be described with reference to Fig. 10. When the user selects to perform the scaling setting 200 on the scaling confirmation screen 160 during the initial setting 100 in Fig. 8, the setting unit 61 first causes the display unit 20 to display a display value setting screen 201, as shown in Fig. 10.

[0091] The display value setting screen 201 includes options for setting a unit and a decimal point position. Depending on the user's selection on the display value setting screen 201, the display on the display unit 20 transitions to a unit setting screen 202 or a decimal point position setting screen 203.

[0092] In the unit setting screen 202, the unit in which the measurement value to be displayed on the auxiliary display section 26 of the display section 20 in the measurement mode 500 is displayed is set. For example, the display section 20 displays options such as distance units such as m and mm, volume units such as L (liter) and cubic meters, weight units such as g (gram), and percentage units such as percentage (%) of the full value. If a unit other than the distance unit is selected here, the measurement value displayed on the auxiliary display section 26 is a value obtained by converting the level Y measured by the level meter 10 into the amount of the contents 72 in the container 70. When the weight unit is set, it is preferable to set the specific gravity of the contents 72. For example, when the weight unit is set, the display section 20 may transition to a screen for setting the specific gravity of the contents 72.

[0093] The decimal point position setting screen 203 sets how many digits the integer portion and the decimal portion will have for the measurement value displayed on the auxiliary display section 26 of the display section 20 in the measurement mode 500. For example, a number of display examples each having a different decimal point position may be displayed on the display section 20, and the user may select a display example corresponding to the decimal point position desired.

[0094] When the setting on the display value setting screen 201 is completed, the setting unit 61 then performs container setting 210 in scaling setting 200. The container setting 210 in scaling setting 200 includes a bottom distance setting screen 211 and an upper surface distance setting screen 212 similar to the container setting 210 in the operation setting 300 in Fig. 9, as well as a tank shape setting screen 220, a capacity setting screen 230, and the like.

[0095] In the container setting 210 in the scaling setting 200, the setting unit 61 first displays the tank shape setting screen 220 on the display unit 20. In the tank shape setting screen 220, the shape of the container 70 to which the level gauge 10 is to be attached is set as one of the container information. As a specific example, the shape corresponding to the container 70 may be selected from options such as a straight tank (a vertically placed cylindrical tank, a prismatic tank, etc.), a horizontally placed cylindrical tank, a spherical tank, a pyramidal tank, and a conical bottom tank. In order to accommodate a container 70 with a complex shape, it is also possible to set a multi-point correction that determines the correspondence between the level Y of the contained item 72 and the volume by a plurality of correction points.

[0096] When the setting on the tank shape setting screen 220 is completed, the setting unit 61 then sequentially displays a bottom distance setting screen 211 and a top distance setting screen 212 on the display unit 20, and sets the bottom distance Y0 and top distance Y1 of the container 70 in sequence.

[0097] When the setting on the top surface distance setting screen 212 is completed, the setting unit 61 then causes the display unit 20 to display the capacity setting screen 230. On the capacity setting screen 230, the full amount value of the container 70 is set as a volume value as one of the container information. Specifically, the volume of the contents 72 when the level Y of the contents 72 reaches the position of the top surface inside the container 70 may be set as the full amount value. The value of the level Y when the contents 72 reaches the full amount value corresponds to the value of the height of the container 70. This value of the height of the container 70 corresponds to the difference, Y0-Y1, between the bottom distance Y0 of the container 70 set on the bottom distance setting screen 211 and the top surface distance Y1 set on the top surface distance setting screen 212.

[0098] When the settings on the capacity setting screen 230 are completed, the scaling setting 200 is completed, and the screen transition of the display unit 20 merges with the operation setting 300 in Fig. 9. Depending on the contents set on the tank shape setting screen 220, setting items in the container setting 210 may be added or changed.

[0099] For example, if the container 70 is a conical bottom tank, pyramidal tank, or the like, and includes an inclined shape, and the value of the level Y and the volume of the contained contents 72 are not in a simple proportional relationship, then the bottom height setting screen 240 is displayed on the display unit 20 after the top distance setting screen 212 and before the capacity setting screen 230. In the bottom height setting screen 240, the height from the bottom of the container 70 to the top end of the inclined shape (the position where it becomes a straight shape) is set.

[0100] Furthermore, when multi-point correction is selected on the tank shape setting screen 220, a multi-point correction screen 250 is displayed on the display unit 20 instead of the capacity setting screen 230. On the multi-point correction screen 250, a combination of the value of the level Y of the contents 72 and the value of the volume of the contents 72 corresponding to that value is set as one correction point, and multiple correction points are set.

[0101] In the above manner, the initial setting 100 of the level meter 10 is performed. In this initial setting 100, the setting unit 61 sequentially displays screens for setting the container information about the container 70 and a plurality of level setting values ​​about the level Y on the display unit 20, so that the container information and the level setting values ​​are sequentially set. The display screens of the display unit 20 are changed one by one in response to the user's operation. Then, in each display screen, a setting item corresponding to the displayed display screen is set among a plurality of setting items including the container information and the level design value. This allows the level meter 10 to complete the setting of a plurality of setting items by itself. Therefore, when setting for level measurement, the user does not need to, for example, connect wiring for wired communication or set wireless communication to allow the level meter 10 to communicate with an external device, which simplifies the user's work.

[0102] Hereinafter, the individual screens displayed on the display unit 20 in the initial setting 100 will be described in more detail with reference to the drawings. Fig. 11 shows a language setting screen 110 displayed on the display unit 20 when the initial setting 100 starts.

[0103] A language setting screen 110 displays a number of language options (English, Japanese, Chinese, and German in FIG. 11). When there are a number of options, a cursor 112 is displayed, and the user can move the cursor 112 by operating the direction key 33. For example, when the up key 36 is operated, the cursor 112 moves to the upper option, and when the down key 35 is operated, the cursor 112 moves to the lower option.

[0104] A confirmation key guide display 113 is displayed at the bottom of language setting screen 110. The confirmation key guide display 113 includes an icon imitating a key used to confirm an option (here, center key 39), and a character string indicating that the option can be confirmed by operating the key indicated by the icon. Note that the character string displayed here changes depending on the language of the option over which cursor 112 is positioned. The user can confirm the display language by operating center key 39 with cursor 112 positioned over the desired display language.

[0105] When the display language is determined, a setup start confirmation screen 120 shown in Fig. 12 is displayed on the display unit 20. In Fig. 12, the setup start confirmation screen 120 is displayed superimposed (overlapped) on the language setting screen 110.

[0106] The setup start confirmation screen 120 includes a character string display area 121 that displays a character string ("Do you want to set up?") that asks whether to start setup (initial setup), and options to start setup immediately ("Yes") and to not start setup yet ("No"). A cursor 122 is displayed hovering over one of the options.

[0107] At the bottom of the setup start confirmation screen 120, a decision key guide display 123 and a back key guide display 124 are displayed. The decision key guide display 123 includes an icon of the center key 39 and the character string "decide", similar to the decision key guide display 113 of the language setting screen 110. The back key guide display 124 includes an icon imitating a key (here, the left key 38) for returning the displayed content to the previous screen (here, the language setting screen 110), and a character string indicating that the displayed content can be returned to the previous screen by operating the key indicated by the icon. Displays equivalent to the cursor 122, decision key guide display 123, and back key guide display 124 are also displayed on other screens, but descriptions of these will be omitted below.

[0108] When “No” is selected on the setup start confirmation screen 120, a distance measurement value confirmation screen 130 shown in Fig. 13 is displayed on the display unit 20. The distance measurement value confirmation screen 130 includes a level gauge icon 131, a measurement reference surface line 132, a container bottom line 133, a distance measurement value display 134, and a container icon 135.

[0109] The level gauge icon 131 is an icon representing the level gauge 10, and imitates the level gauge 10. The level gauge icon 131 is displayed above the container icon 135. The measurement reference surface line 132 is a line representing the measurement reference surface XS of the level gauge 10, and extends horizontally from a position of the level gauge icon 131 that corresponds to the measurement reference surface XS. The container icon 135 is an icon representing the container 70, and here, a shape imitating a straight tank is displayed. The container bottom line 133 is a line representing the bottom of the container 70, and extends horizontally from a position of the container icon 135 that corresponds to the bottom. The distance measurement value display 134 indicates the value of the distance measured by the level gauge 10. The distance measurement value display 134 displays the distance (here, 500 mm) from the measurement reference surface XS of the level gauge 10 to an object that reflects the measurement signal Tx as a numerical value.

[0110] In addition, on the distance measurement value confirmation screen 130, an arrow extends from the measurement reference plane line 132 toward the bottom of the container icon 135. This indicates that when the level meter 10 is attached to an empty container 70 (containing no contents 72), the distance from the measurement reference plane XS to the bottom of the container 70 is measured by the level meter 10 and displayed on the distance measurement value display 134. If the user determines on the distance measurement value confirmation screen 130 that the level meter 10 is correctly attached to the container 70, the user may return to the setup start confirmation screen 120 and start the setup.

[0111] When "Yes" is selected on the setup start confirmation screen 120 of Fig. 12, an input / output setting screen 140 shown in Fig. 14 is displayed on the display unit 20. The input / output setting screen 140 includes options for a PNP / NPN setting screen 141, options for a number of control outputs setting screen 142, options for an external input setting screen 143, and an option 144 for proceeding to the next setting. Each option also displays a character string (such as "PNP", "4", or "OFF") indicating the setting content set on the PNP / NPN setting screen 141, the number of control outputs setting screen 142, or the external input setting screen 143. The input / output setting screen 140 also includes a scroll bar 145, an up key display 146, and a down key display 147.

[0112] The scroll bar 145 indicates the relative position of the option currently pointed to in the entire options on a screen where multiple options are displayed side by side. The up key display 146 is an icon imitating the up key 36, and when this icon is dark, it indicates that the cursor can be moved up by operating the up key 36. On the other hand, when the up key display 146 is light in color (white in FIG. 14) as shown in FIG. 14, it indicates that the cursor is pointed to the option at the top and the cursor cannot be moved up any further. The down key display 147 is an icon imitating the down key 35, and when this icon is dark in color (dot pattern in FIG. 14) as shown in FIG. 14, it indicates that the cursor can be moved down by operating the down key 35. On the other hand, when the down key display 147 is light in color, it indicates that the cursor is pointed to the option at the bottom and the cursor cannot be moved down any further. Hereinafter, the explanation of the scroll bar 145, the up key display 146, and the down key display 147 on other screens will be omitted.

[0113] When the center key 39 is operated with the cursor positioned on any of the options on the PNP / NPN setting screen 141, the options on the number of control outputs setting screen 142, or the options on the external input setting screen 143, the display on the display unit 20 transitions to the PNP / NPN setting screen 141, the number of control outputs setting screen 142, or the external input setting screen 143 according to the option selected. Details of the PNP / NPN setting screen 141, the number of control outputs setting screen 142, and the external input setting screen 143 are not shown, but as described above, each setting screen displays options of "PNP" and "NPN," options of 0, 1, 2, 3, 4, 5, options of "OFF" and "ON," etc.

[0114] When the center key 39 is operated with the cursor positioned on option 144 (character string "Confirm and Next") for proceeding to the next setting on the input / output setting screen 140, the display on the display unit 20 transitions to a distance unit setting screen 150 shown in Fig. 15. On the distance unit setting screen 150, a distance unit for expressing the measurement value of the level meter 10 is set. For example, as shown in Fig. 15, the distance unit setting screen 150 displays options of "mm" (millimeter) or "m" (meter).

[0115] When the distance unit is set on the distance unit setting screen 150, the display on the display unit 20 transitions to a scaling confirmation screen 160 shown in Fig. 16. On the scaling confirmation screen 160, it is possible to select whether or not to execute the scaling setting 200. For example, as shown in Fig. 16, the scaling confirmation screen 160 displays a choice between "OFF" and "ON." If "ON" is selected here, the scaling setting 200 is executed, and if "OFF" is selected, the operation setting 300 is executed.

[0116] When "OFF" is selected on the scaling confirmation screen 160 and operation setting 300 is performed, the display unit 20 first displays a bottom distance setting screen 211 shown in Fig. 17. The bottom distance setting screen 211 includes a level gauge icon 131, a measurement reference surface line 132, a container icon 135, and a bottom distance setting field 215. Although the container bottom line 133 is also shown in Fig. 17, the container bottom line 133 does not have to be displayed on the bottom distance setting screen 211.

[0117] In the bottom distance setting screen 211, the distance (bottom distance Y0) from the measurement reference surface XS of the level meter 10 to the bottom of the container 70 is set by the setting unit 61. In the bottom distance setting screen 211, an arrow extending from the measurement reference surface line 132 to the bottom of the container icon 135 (the position of the container bottom line 133) is displayed. This arrow indicates that the numerical value set in the bottom distance setting screen 211 is the distance from the measurement reference surface XS to the bottom of the container 70. In addition, in FIG. 17, the word "0%" is displayed next to the container bottom line 133 to indicate that the measured value of the distance by the level meter 10 is the bottom distance Y0 when the amount of the contents 72 in the container 70 is 0% (empty state) of the full amount (100%). In the bottom distance setting field 215, candidates for the distance to the bottom are displayed as numerical values. In this way, when the container information is set by the setting unit 61, the level meter icon 131 indicating the level meter 10 and the container icon 135 indicating the container 70 are displayed on the display unit 20, so that the user can easily visually understand how the set value relates to the level meter 10 and the container 70. Here, the distance measurement unit (mm in this case) displayed in the bottom distance setting field 215 uses the distance unit set on the distance unit setting screen 150. Similarly, when the distance unit is displayed below, the distance unit set on the distance unit setting screen 150 is used.

[0118] When the user operates the down key 35 and the up key 36 on the bottom distance setting screen 211, the value displayed in the bottom distance setting field 215 decreases and increases. Then, when the user operates the determination key (center key 39), the value displayed in the bottom distance setting field 215 (here, 5000 mm) is input to the level meter 10. The setting unit 61 sets the input value as the bottom distance Y0, which is one of the container information. The set value is stored in the memory unit 63 when the initial setting 100 is completed. The user may input, for example, the design value of the tank used as the container 70 as the bottom distance Y0 of the container 70. Note that a value different from the design value may be input depending on various measurement conditions such as the measurement target and the installation state of the level meter 10.

[0119] When the bottom distance Y0 of the container 70 is set on the bottom distance setting screen 211, the display on the display unit 20 transitions to a top surface distance setting screen 212 shown in Fig. 18. The top surface distance setting screen 212 includes a level gauge icon 131, a measurement reference surface line 132, a container icon 135, and a top surface distance setting field 216. In Fig. 18, a container top surface line 217 indicating the top surface inside the container 70 is shown as a line extending horizontally from a position of the container icon 135 that corresponds to the internal top surface, but this container top surface line 217 does not have to be displayed on the top surface distance setting screen 212.

[0120] In the upper surface distance setting screen 212, the distance (upper surface distance Y1) from the measurement reference surface XS of the level meter 10 to the upper surface inside the container 70 is set. In the upper surface distance setting screen 212, an arrow extending from the measurement reference surface line 132 to the position of the upper surface of the container icon 135 is displayed. This arrow indicates that the numerical value set in the upper surface distance setting screen 212 is the distance from the measurement reference surface XS to the upper surface inside the container 70. In addition, in FIG. 18, the word "100%" is displayed next to the container upper surface line 217 to indicate that when the content 72 in the container 70 is full (100%), the measured value of the distance by the level meter 10 is the upper surface distance Y1. Note that, depending on the shape of the container 70, the position of the upper surface inside the container 70 and the position of the full line at which the content 72 is treated as being full may differ. In that case, the distance from the measurement reference surface XS to the full line may be set as the upper surface distance Y1. In the upper surface distance setting field 216, candidates for the upper surface distance Y1 are displayed as numerical values.

[0121] When the down key 35 and the up key 36 are operated by the user on the top surface distance setting screen 212, the numerical value displayed in the top surface distance setting field 216 decreases and increases. Then, when the determination key (center key 39) is operated by the user, the numerical value displayed in the top surface distance setting field 216 (here, 200 mm) is input to the level meter 10. The setting unit 61 sets the input numerical value as the top surface distance Y1, which is one of the container information. The set numerical value is stored in the memory unit 63 when the initial setting 100 is completed. The user may input, for example, the thickness of the top surface plate of the tank used as the container 70 as the top surface distance Y1. Note that a numerical value different from the design value may be input depending on various measurement conditions such as the measurement target and the installation state of the level meter 10. For example, when the level meter 10 is installed further upward from the top surface plate of the tank, a numerical value larger than the thickness of the top surface plate of the tank is input as the top surface distance Y1.

[0122] When the top surface distance Y1 is set on the top surface distance setting screen 212, the display on the display unit 20 transitions to a first threshold setting screen 310 shown in Fig. 19. The first threshold setting screen 310 includes a level gauge icon 131, a container bottom line 133, a container icon 135, a container top surface line 217, a first threshold setting field 311, a height display 312, a first threshold line 313, a first threshold identifier 314, a normally open icon 314a, and a normally closed icon 314b.

[0123] The height display 312 numerically indicates the height of the container 70 (the distance from the bottom of the container 70 to the top surface inside the container 70). As the height display 312, the difference between the bottom distance Y0 set on the bottom distance setting screen 211 and the top surface distance Y1 set on the top surface distance setting screen 212, the value Y0-Y1 (here, 4800), is displayed together with the measurement unit (mm). Meanwhile, the number "0" is displayed above the container bottom line 133 to indicate that the reference for the level Y is the bottom of the container 70, i.e., to indicate that the level Y at the bottom of the container 70 is treated as zero.

[0124] In the first threshold setting screen 310, the first threshold is set as one of a plurality of level setting values ​​related to the level Y. Since the first threshold is one of the level setting values, in FIG. 19, "Setting Value 1" is displayed as the screen name at the top of the first threshold setting screen 310. The first threshold is set as a distance from the bottom of the container 70. Candidates for the first threshold are displayed as numerical values ​​in the first threshold setting field 311. The first threshold line 313 is displayed as a line extending horizontally relative to the container icon 135. This first threshold line 313 is displayed at a height according to the first threshold displayed in the first threshold setting field 311.

[0125] The height of the first threshold line 313 indicates the relative position of the first threshold with respect to the container 70. The relative position of the first threshold is determined based on container information regarding the container 70. Specifically, the higher the ratio of the first threshold to the height of the container 70 (one piece of container information), the higher the first threshold line 313 is positioned relative to the container icon 135. When setting the first threshold (level setting value), the relative position of the first threshold with respect to the container 70 is displayed together with the level gauge icon 131 and the container icon 135, allowing the user to set the level setting value for level Y while visually grasping the relative position with respect to the container 70.

[0126] The first threshold identifier 314 is displayed alongside the first threshold line 313. The first threshold identifier 314 indicates a level setting value identifier assigned to the first threshold. A level setting value identifier is an identifier that is assigned individually to a plurality of level setting values. In FIG. 19, the number "1" is displayed as the level setting value identifier assigned to the first threshold. The level setting value identifier is not limited to numbers, and may be any identifier that can individually identify the level setting value. For example, alphabets or symbols may be used as the level setting value identifier. In FIG. 19, the same identifier as the first threshold identifier 314 is also displayed next to the first threshold setting field 311.

[0127] The normally open icon 314a and the normally closed icon 314b are displayed next to the first threshold identifier 314. The normally open icon 314a is disposed above the normally closed icon 314b. The normally open icon 314a and the normally closed icon 314b indicate the characteristics of the first threshold (the output logic of the external output terminal 12D corresponding to the first threshold).

[0128] The first threshold characteristic is a setting condition that indicates whether the operation of the level meter 10 changes when the level Y exceeds the first threshold (for example, the signal of the external output terminal 12D changes) or when the level Y falls below the first threshold. When the first threshold characteristic is normally open, the operation of the level meter 10 changes when the level Y exceeds the first threshold (for example, one of the outputs of the external output terminal 12D turns ON). In order to indicate that a change occurs when the level Y exceeds the first threshold, the normally open icon 314a is placed above the first threshold line 313. When the first threshold characteristic is normally closed, the operation of the level meter 10 changes when the level Y falls below the first threshold. In order to indicate that a change occurs when the level Y falls below the first threshold, the normally closed icon 314b is placed below the first threshold line 313.

[0129] Of the normally open icon 314a and the normally closed icon 314b, the one that is enabled is displayed in a dark color (a dot pattern in FIG. 19), and the one that is disabled is displayed in a light color (white in FIG. 19). In the initial state, either the normally open icon 314a or the normally closed icon 314b (here, the normally open icon 314a) is enabled.

[0130] When the down key 35 and the up key 36 are operated by the user on the first threshold setting screen 310, the value of the first threshold displayed in the first threshold setting field 311 decreases and increases. As the value of the first threshold changes, the height of the first threshold line 313 also changes. As the height of the first threshold line 313 changes, the heights of the first threshold identifier 314, the normally open icon 314a, and the normally closed icon 314b also change. When the determination key (center key 39) is operated by the user, the value (here, 4000 mm) displayed in the first threshold setting field 311 is input to the level meter 10. The setting unit 61 sets the input value as the first threshold, which is one of the level setting values. The set value is stored in the storage unit 63 when the initial setting 100 is completed. Note that the multiple thresholds (level setting values) including the first threshold are set, for example, as values ​​indicating that "if the level Y exceeds or falls below this value, the amount of the contained contents 72 needs to be adjusted" for the contained contents 72 in the container 70.

[0131] When the first threshold is set, the display on the display unit 20 transitions to an output logic setting screen 315 shown in Fig. 20. The display contents of the output logic setting screen 315 are the same as those of the first threshold setting screen 310. On the output logic setting screen 315, an output logic setting field 316 is displayed instead of the first threshold setting field 311. Also, on the output logic setting screen 315, the numerical value of the first threshold (here, "4000") set on the first threshold setting screen 310 is displayed alongside the first threshold identifier 314 (next to the normally open icon 314a and the normally closed icon 314b in Fig. 20).

[0132] In the output logic setting screen 315, an ON icon 316a and an OFF icon 316b are displayed alongside the output logic setting field 316. The ON icon 316a and the OFF icon 316b visually indicate the characteristics (output logic) of the first threshold. When the characteristics of the first threshold are normally open, the ON icon 316a is arranged above the OFF icon 316b to indicate that the operation of the level meter 10 changes (becomes the ON state) when the level Y exceeds the first threshold. On the other hand, although not shown in FIG. 20, when the characteristics of the first threshold are normally closed, the ON icon 316a is arranged below the OFF icon 316b to indicate that the operation of the level meter 10 changes (becomes the ON state) when the level Y falls below the first threshold. The ON icon 316a is displayed in a dark color (a dot pattern in FIG. 20) indicating an enabled state, and the OFF icon 316b is displayed in a light color (white in FIG. 20) indicating an disabled state.

[0133] In the output logic setting screen 315, an output logic related to the first threshold is set. Specifically, whether the characteristic of the external output terminal 12D corresponding to the first threshold is normally open or normally closed is set. In the output logic setting field 316, a character string of "NO" indicating that the characteristic is normally open (Normal Open) or a character string of "NC" indicating that the characteristic is normally closed (Normal Close) is displayed. When the down key 35 and the up key 36 are operated by the user, the character string displayed in the output logic setting field 316 switches between "NO" and "NC". As the character string in the output logic setting field 316 switches, the positions of the ON icon 316a and the OFF icon 316b are swapped. As the character string in the output logic setting field 316 switches, the enabled and disabled states of the normally open icon 314a and the normally closed icon 314b are also switched.

[0134] 20, when the display in the output logic setting field 316 is "NO", the icons in the valid state (valid normally open icon 314a and ON icon 316a) are arranged above the icons in the invalid state (invalid normally closed icon 314b and OFF icon 316b). On the other hand, when the display in the output logic setting field 316 is "NC", the icons in the valid state (valid normally closed icon 314b and ON icon 316a) are arranged below the icons in the invalid state (invalid normally open icon 314a and OFF icon 316b).

[0135] When the user operates the enter key (center key 39) on the output logic setting screen 315, the characteristic (normally open or normally closed) corresponding to the character string displayed in the output logic setting field 316 is set as the output logic related to the first threshold. The setting unit 61 also sets the selection result of the option related to such a threshold as one of the level setting values ​​related to the level Y.

[0136] When the output logic for the first threshold is set, the display on the display unit 20 transitions to a second threshold setting screen 320 shown in Fig. 21. On the second threshold setting screen 320, similar to the various display components displayed on the first threshold setting screen 310 for setting the first threshold, a second threshold line 323, a second threshold identifier 324, a normally open icon 324a for the second threshold, a normally closed icon 324b for the second threshold, and a second threshold setting field 326 are displayed.

[0137] The second threshold setting screen 320 also displays a first threshold line 313 and a first threshold identifier 314 relating to the first threshold that has already been set, the numerical value of the first threshold (here, 4000), and the like. However, in order to distinguish it from the second threshold that is currently being set, the display components relating to the first threshold are displayed in an inconspicuous manner (for example, grayed out). When setting a new level setting value (second threshold), the relative position of the previously set level setting value (first threshold) with respect to the container 70 is displayed, so that the user can set the new level setting value while being aware of the relative relationship with the previously set level setting value.

[0138] When the second threshold is set on the second threshold setting screen 320, the display on the display unit 20 transitions to an output logic setting screen related to the second threshold. Although the output logic setting screen related to the second threshold is not shown, the display contents of the output logic setting screen related to the second threshold take over the display contents of the second threshold setting screen 320. Setting of the output logic related to the second threshold is performed in the same manner as the output logic setting screen 315 (FIG. 20) for the first threshold.

[0139] The setting of the threshold value and the output logic setting of the threshold value are repeated the same number of times as the number of control outputs (the number of control signals) set on the control output number setting screen 142 transitioned from the input / output setting screen 140 in FIG. 14. When a new threshold value is set, not only the relative position of the new threshold value with respect to the container 70 is displayed, but also the relative positions of all threshold values ​​already set with respect to the container 70 are displayed. Note that, in this example, the setting of the threshold value and the output logic setting are combined and performed sequentially for each threshold value, but the output logic settings of all threshold values ​​may be performed sequentially after only the values ​​of all threshold values ​​are set sequentially. For example, the first threshold setting screen 310 and the second threshold setting screen 320 may be displayed in this order, and then the output logic setting screen 315 for the first threshold value and the output logic setting screen 315 for the second threshold value may be displayed in this order.

[0140] When the setting of all the threshold values ​​and output logic is completed, the display on the display unit 20 transitions to an indicator light pattern setting screen 380 shown in FIG. 22. Here, it is assumed that four threshold values ​​are set. The indicator light pattern setting screen 380 includes a level gauge icon 131, a container icon 135, a virtual color gauge 385, and an indicator light pattern setting field 381. The level gauge icon 131 displayed on the indicator light pattern setting screen 380 includes an indicator light icon 382 that virtually indicates a change in the lighting state of the indicator light 52 in accordance with an increase or decrease in the level Y. In addition, a virtual bar display 383 that virtually indicates the expansion and contraction of the bar display 22 (in the measurement mode 500) in accordance with an increase or decrease in the level Y is displayed within the container icon 135 displayed on the indicator light pattern setting screen 380.

[0141] It is preferable that this virtual bar display 383 be visually recognizable that the longer the virtual bar display 383 is, the more contents 72 (e.g., liquid) are virtually shown to be contained in the container 70. For example, it is preferable that the virtual bar display 383 is colored blue, and a gradation display is provided in which the density of the blue changes stepwise within the container icon 135. For example, it is preferable that the virtual bar display 383 is dark blue on the lower end side (close to the bottom of the container icon 135) and light blue on the upper end side (close to the top surface of the container icon 135), with the density changing stepwise (or continuously) from dark blue to light blue.

[0142] A virtual bar arrow 384 is displayed at the top end of the virtual bar display 383. The virtual bar arrow 384 extends horizontally toward the virtual color gauge 385. The virtual color gauge 385 is displayed alongside the container icon 135. The virtual color gauge 385 is a gauge with the same length as the overall length of the container icon 135 (the distance from the bottom position to the top surface position). The virtual color gauge 385 is color-coded into a plurality of sections. The boundaries between the sections of the virtual color gauge 385 are relative positions of each threshold value with respect to the overall length of the container icon 135. In FIG. 22, four threshold values ​​are set, and the virtual color gauge 385 is divided into five sections.

[0143] A level setting value identifier assigned to the corresponding threshold is displayed next to the boundary between the sections of the virtual color gauge 385. In Fig. 22, the first threshold identifier 314, the second threshold identifier 324, the third threshold identifier 334, and the fourth threshold identifier 344 are displayed in order from the top. Also, the color of the indicator light icon 382 is the same as the color of the section of the virtual color gauge 385 indicated by the virtual bar arrow 384. In Fig. 22, the virtual bar arrow 384 indicates the third section from the top, and the indicator light icon 382 is the same color as the third section from the top.

[0144] When the down key 35 and the up key 36 are operated by the user on the indicator light pattern setting screen 380, the pattern name displayed in the indicator light pattern setting field 381 ("Pattern 1" in FIG. 22) is switched. A plurality of pattern names are prepared, and the color-coding pattern for each section of the virtual color gauge 385 changes according to the pattern name. In "Pattern 1," the five sections of the virtual color gauge 385 are color-coded with three colors. Specifically, the top and bottom sections are a first color (e.g., red), the second and fourth sections from the top are a second color (e.g., yellow), and the third section from the top (center) is a third color (e.g., green). The color-coding pattern of the virtual color gauge 385 corresponds to a change pattern of the lighting state of the indicator light 52 with an increase or decrease in the level Y.

[0145] Then, on the indicator light pattern setting screen 380, an animation image is displayed which shows a change in the operation of the level meter 10 in accordance with an increase or decrease in the level Y. This animation image includes a virtual bar display 383 and an indicator light icon 382. Specifically, while the indicator light pattern setting screen 380 is displayed, the virtual bar display 383 repeatedly expands and contracts. For example, the virtual bar display 383 expands from the bottom to the top of the container icon 135, and when it reaches the top, it starts to contract. Then, when the virtual bar display 383 contracts to the bottom of the container icon 135, the virtual bar display 383 starts to expand again. Note that the expansion and contraction of this virtual bar display 383 does not show a change in the actual level Y, but shows a change in a virtual measurement value (dummy value).

[0146] As the virtual bar display 383 expands and contracts, the state (color) of the indicator light icon 382 also changes. FIG. 23 shows the change by animation of the indicator light pattern setting screen 380. In FIG. 23, the virtual bar display 383 expands more than in the state of FIG. 22, and the virtual bar arrow 384 indicates the second section from the top of the virtual color gauge 385. Then, the color of the indicator light icon 382 changes to the color of the second section from the top. In this way, the indicator light pattern setting screen 380 displays an animation image including the virtual bar display 383 that repeatedly expands and contracts, and the indicator light icon 382 whose color changes as the virtual bar display 383 expands and contracts. The virtual bar display 383 repeatedly expands and contracts, and thus the expansion and contraction of the bar display 22 in accordance with the increase and decrease of the level Y in the measurement mode 500 is virtually shown. Also, the color of the indicator light icon 382 changes as the virtual bar display 383 expands and contracts, and thus the change in the lighting state of the indicator light 52 in accordance with the increase and decrease of the level Y is virtually shown.

[0147] Furthermore, while the indicator light pattern setting screen 380 is displayed on the display unit 20, the indicator light 52 may actually be lit, and the actual lighting color of the indicator light 52 may change in conjunction with the change in color of the indicator light icon 382. In other words, it is preferable that the actual lighting color of the indicator light 52 changes in conjunction with the movement of the animation image displayed on the indicator light pattern setting screen 380. By linking the animation image of the indicator light pattern setting screen 380 with the indicator light 52, the user can easily visually grasp how the lighting state of the indicator light 52 changes as the level Y increases or decreases.

[0148] The color-coding pattern for each section of the virtual color gauge 385 changes according to the pattern name displayed in the indicator light pattern setting field 381. FIG. 24 shows the color-coding pattern in "Pattern 2" (second indicator light pattern). In FIG. 24, the topmost section and the bottommost section are the same color (e.g., red). The second section from the top is a different color (e.g., green) from the topmost section, and the third section from the top and the fourth section from the top are also the same color (e.g., green) as the second section from the top. In FIG. 24, the virtual bar arrow 384 indicates the bottom end of the topmost section, and the indicator light icon 382 is the same color (e.g., red) as the topmost section.

[0149] The animation image continues to move even if the pattern name displayed in the indicator light pattern setting field 381 is changed. When the color coding of the sections is changed in accordance with a change in the pattern name, the color of the section indicated by the virtual bar arrow 384 changes, and accordingly the lighting color of the indicator light icon 382 and the indicator light 52 may also change.

[0150] When the user operates the enter key (center key 39) on the indicator light pattern setting screen 380, the setting unit 61 sets the color-coding pattern of the virtual color gauge 385 corresponding to the pattern name displayed in the indicator light pattern setting field 381 as a change pattern of the lighting state of the indicator lights 52 in accordance with an increase or decrease in the level Y. Specifically, the setting unit 61 divides the measured level Y into a plurality of level ranges according to the set threshold value, and assigns the color of each section of the virtual color gauge 385 to each level range.

[0151] Note that each section of the virtual color gauge 385 does not necessarily have to be color-coded, and for example, all sections may have a pattern of the same color. Also, the change in the lighting state of the indicator light 52 indicated by the indicator light icon 382 includes not only a change in the lighting color but also a change to an off state or a blinking state. Depending on the pattern, at least one of the sections of the virtual color gauge 385 may display a state in which the indicator light 52 is off or a state in which the indicator light 52 is blinking. Then, the indicator light icon 382 may indicate the off state or the blinking state of the indicator light 52 according to the expansion and contraction of the virtual bar display 383. Furthermore, it is preferable that the actual lighting state of the indicator light 52 changes in conjunction with the change in the lighting state (including the lighting color, the off state, and the blinking state) of the indicator light icon 382.

[0152] In addition, the options for the indicator light pattern may not only be predetermined patterns, but also allow the user to set an original pattern. For example, when the enter key (center key 39) is operated in a state where "Custom" is displayed in the indicator light pattern setting field 381, the display on the display unit 20 may transition to a custom pattern setting screen (not shown) where the user can set an original pattern for the lighting state of the indicator light 52.

[0153] When the change pattern of the lighting state of the indicator lamp 52 is set on the indicator lamp pattern setting screen 380, the display on the display unit 20 transitions to a setup completion confirmation screen 390 shown in Fig. 25. When the enter key (center key 39) is operated on the setup completion confirmation screen 390, the initial settings 100 are completed, and the contents set on the individual setting screens of the initial settings 100 are collectively stored in the memory unit 63. Thereafter, the level meter 10 transitions to the measurement mode 500 of Fig. 7.

[0154] The setup completion confirmation screen 390 in FIG. 25 includes a level gauge icon 131, a container bottom line 133, a container icon 135, a container top line 217, a virtual bar display 383, a virtual bar arrow 384, and a virtual color gauge 385. The level gauge icon 131 includes an indicator light icon 382. In addition, a first threshold identifier 314, a second threshold identifier 324, a third threshold identifier 334, and a fourth threshold identifier 344 are displayed next to the virtual bar display 383. Above the container bottom line 133, a value (0) of the level Y at the bottom of the container 70 is displayed. Above the container top line 217, a value (4800) of the height of the container 70 is displayed. Note that, instead of the height of the container 70, the distance from the level gauge 10 to the bottom of the container 70 may be displayed.

[0155] The setup completion confirmation screen 390 collectively displays the numerical values ​​of the multiple thresholds (level setting values) set by the setting unit 61 in the initial setting 100. Specifically, as shown in Fig. 25, the first threshold identifier 314, the second threshold identifier 324, the third threshold identifier 334, and the fourth threshold identifier 344, which are individually assigned to the thresholds, are displayed along with the numerical values ​​of the first threshold (4000 in this case), the second threshold (3000 in this case), the third threshold (2000 in this case), and the fourth threshold (1000 in this case) corresponding to these identifiers.

[0156] Furthermore, the setup completion confirmation screen 390 displays the numerical values ​​of the multiple thresholds (level setting values) as well as the relative positions of the thresholds with respect to the container 70. Specifically, the higher the ratio of the numerical values ​​of the first threshold, second threshold, third threshold, and fourth threshold to the height value of the container 70, the higher the first threshold identifier 314, second threshold identifier 324, third threshold identifier 334, and fourth threshold identifier 344 are displayed with respect to the container icon 135. In other words, the relative positions of the first threshold identifier 314, second threshold identifier 324, third threshold identifier 334, and fourth threshold identifier 344 with respect to the container icon 135 indicate the relative positions of the first threshold, second threshold, third threshold, and fourth threshold with respect to the container 70.

[0157] In the setup completion confirmation screen 390, the relative position of each threshold value (level setting value) with respect to the container 70 is displayed on the display unit 20, and the height value of the container 70 (here, 4800 mm) is also displayed. Note that the bottom distance Y0 may be displayed instead of the height of the container 70. In this manner, the setup completion confirmation screen 390 displays the container information and the level setting value set in the initial setting 100 all together. By checking the setup completion confirmation screen 390, the user can check whether the setting items in the initial setting 100 have been set correctly.

[0158] Furthermore, in the setup completion confirmation screen 390, an animation image is displayed showing a change in the operation of the level meter 10 accompanying an increase or decrease in the level Y in the indicator light pattern setting screen 380. This animation image includes a virtual bar display 383 and an indicator light icon 382. Specifically, in the setup completion confirmation screen 390, the virtual bar display 383 repeatedly expands and contracts in the same manner as in the indicator light pattern setting screen 380. As the virtual bar display 383 expands and contracts, the lighting state of the indicator light icon 382 changes.

[0159] It is also preferable that the setup completion confirmation screen 390 allows the user to confirm a change in the output signal of the external output terminal 12D as an example of a change in the operation of the level meter 10 accompanying an increase or decrease in the level Y. Specifically, when the output signal of the external output terminal 12D corresponding to each threshold value becomes valid as the level Y increases or decreases, the identifier assigned to each threshold value is highlighted. Also, the signal output from the external output terminal 12D may actually change.

[0160] For example, in Fig. 25, if the characteristics (output logic) of the first threshold, the second threshold, the third threshold, and the fourth threshold are all normally open, while the virtual bar arrow 384 indicates a value below the fourth threshold identifier 344, the signals of the external output terminal 12D corresponding to the first threshold, the second threshold, the third threshold, and the fourth threshold are all invalid (open, OFF). Then, as shown in Fig. 25, when the virtual bar display 383 extends and the virtual bar arrow 384 indicates a value above the fourth threshold identifier 344 (the level Y virtually exceeds the fourth threshold), only the signal of the external output terminal 12D corresponding to the fourth threshold becomes valid (closed, ON). In Fig. 25, the frame of the fourth threshold identifier 344 is highlighted with a thick frame to indicate that the signal of the external output terminal 12D corresponding to the fourth threshold is valid. On the other hand, the signals of the external output terminal 12D corresponding to the first threshold, the second threshold, and the third threshold remain disabled, so that the frames of the first threshold identifier 314, the second threshold identifier 324, and the third threshold identifier 334 remain in the normal state. After that, as the virtual bar display 383 extends, the third threshold identifier 334, the second threshold identifier 324, and the first threshold identifier 314 are highlighted in order.

[0161] In this way, by displaying an animation image showing the change in the operation of the level meter 10 in response to an increase or decrease in the level Y on the setup completion confirmation screen 390, the user can visually understand how the operation of the level meter 10 changes in response to an increase or decrease in the level Y. Therefore, the user can check whether the settings made in the initial setting 100 were appropriate before the settings are actually applied.

[0162] Next, a description will be given of the display on the display unit 20 when "ON" is selected on the scaling confirmation screen 160 shown in Fig. 16 and scaling setting 200 is performed. When scaling setting 200 is performed, first, a display value setting screen 201 shown in Fig. 26 is displayed on the display unit 20.

[0163] The display value setting screen 201 includes options for a unit setting screen 202, options for a decimal point position setting screen 203, and an option 204 for proceeding to the next setting. Each option also displays a character string (such as "L" or "99999") indicating the setting content set on the unit setting screen 202 and the decimal point position setting screen 203.

[0164] Depending on the user's selection, the display on the display unit 20 transitions from the display value setting screen 201 to a unit setting screen 202 or a decimal point position setting screen 203. Although details of the unit setting screen 202 are not shown, the unit setting screen 202 displays options for the unit of the display value, such as m, mm, L, g, and %, and the unit of the option selected by the user is set as the unit of the display value.

[0165] 27 shows the decimal point position setting screen 203. On the decimal point position setting screen 203, a number of display examples with different decimal point display positions ("99999", "9999.9", "999.99", "99.999", "9.9999") are displayed. By selecting a display example corresponding to the decimal point display position desired by the user, it is possible to set how many digits the integer part and the decimal part will have for the measured value displayed on the auxiliary display section 26 of the display section 20 in the measurement mode 500.

[0166] When option 204 for proceeding to the next setting is selected on display value setting screen 201, the display on display unit 20 transitions to a tank shape setting screen 220 shown in Fig. 28. The tank shape of the container 70 is set on tank shape setting screen 220. The tank shape is treated as part of container information related to the container 70. The tank shape setting screen 220 includes a tank shape setting field 221 and a tank shape display field 222.

[0167] The name of the tank shape is displayed in the tank shape setting field 221. When the down key 35 and the up key 36 are operated by the user on the tank shape setting screen 220, the name displayed in the tank shape setting field 221 is switched. In Fig. 28, "straight tank" is displayed as the name of the tank shape.

[0168] The tank shape display field 222 shows an illustration of the tank shape corresponding to the name shown in the tank shape setting field 221. In Fig. 28, illustrations of a vertically placed cylindrical tank and a square prism tank are shown as the tank shape of a "straight tank".

[0169] When the enter key (center key 39) is operated on the tank shape setting screen 220, the tank shape named in the tank shape display field 222 is set as the tank shape of the container 70. Then, the display on the display unit 20 transitions to a bottom distance setting screen 211 and a top distance setting screen 212 corresponding to the tank shape. The bottom distance setting screen 211 and the top distance setting screen 212 corresponding to a straight tank are similar to those shown in Figs. 17 and 18.

[0170] When the bottom distance Y0 and the top surface distance Y1 are set on the bottom distance setting screen 211 and the top surface distance setting screen 212, the display on the display unit 20 transitions to a capacity setting screen 230 shown in Fig. 29. The capacity setting screen 230 in Fig. 29 corresponds to a straight tank.

[0171] The capacity setting screen 230 includes a level gauge icon 131, a container icon 135, and a capacity setting field 231. The container icon 135 represents a state (full state) in which the liquid is filled up to the top surface of the "straight tank." The capacity setting field 231 displays a candidate value for the full amount of the container 70. The candidate value for the full amount is displayed as a volume value (for example, L: liters). When the down key 35 and the up key 36 are operated on the capacity setting screen 230, the value displayed on the capacity setting field 231 increases or decreases. When the enter key (center key 39) is operated on the capacity setting screen 230, the value displayed on the capacity setting field 231 is set as the full amount (tank capacity) of the container 70. The tank capacity is treated as a part of the container information regarding the container 70.

[0172] Next, cases where the shape of the container 70 is other than a "straight tank" will be described. Fig. 30 shows a case where the name (option) of the tank shape displayed in the tank shape setting field 221 on the tank shape setting screen 220 is a "spherical tank". In Fig. 30, an illustration of a spherical tank is displayed in the tank shape display field 222.

[0173] Even when a spherical tank is selected as the tank shape, the bottom distance Y0 is set on the bottom distance setting screen 211, the top distance Y1 is set on the top distance setting screen 212, and the tank capacity is set on the capacity setting screen 230. FIG. 31 is a diagram showing the bottom distance setting screen 211 for a spherical tank. FIG. 32 is a diagram showing the top distance setting screen 212 for a spherical tank. FIG. 33 is a diagram showing the capacity setting screen 230 for a spherical tank. As shown in FIGS. 31, 32, and 33, when the tank shape is a spherical tank, the shape of the container icon 135 is different from that of a straight tank. Even when the tank shape is another tank shape, the shape of the container icon 135 displayed when setting the container information corresponds to the selected tank shape.

[0174] Even when the tank shape is spherical, the bottom distance Y0 corresponding to the distance from the measurement reference plane line 132 to the container bottom line 133 is set on the bottom distance setting screen 211 (Fig. 31). Also, the top surface distance Y1 corresponding to the distance from the measurement reference plane line 132 to the container top surface line 217 is set on the top surface distance setting screen 212 (Fig. 32). In a spherical tank, the container bottom line 133 is a line that extends horizontally from the bottom end of the spherical tank. In a spherical tank, the container top surface line 217 is a line that extends horizontally from the top end of the spherical tank.

[0175] When the tank shape is a spherical tank, the relationship between the measured level Y and the volume of the contents 72 in the container 70 is not a simple proportional relationship. The level meter 10 can calculate the relationship between the measured level Y and the volume of the contents 72 in the container 70 based on the set bottom distance Y0, top distance Y1, and tank capacity, and on the fact that the tank (container 70) is spherical.

[0176] Fig. 34 shows a case where the name (option) of the tank shape displayed in the tank shape setting field 221 on the tank shape setting screen 220 is "cylindrical tank (horizontal)". In Fig. 34, an illustration of a horizontal cylindrical tank is displayed in the tank shape display field 222.

[0177] Even when a horizontally placed cylindrical tank is selected as the tank shape, the bottom distance Y0 is set on the bottom distance setting screen 211, the top surface distance Y1 is set on the top surface distance setting screen 212, and the tank capacity is set on the capacity setting screen 230. Based on these settings and the fact that the tank shape is a horizontally placed cylindrical tank, the level meter 10 can calculate the relationship between the measured level Y and the volume of the contents 72 in the container 70.

[0178] Figure 35 shows a case where the name (option) of the tank shape displayed in the tank shape setting field 221 on the tank shape setting screen 220 is "conical bottom tank." In Figure 35, an illustration of a conical bottom tank is displayed in the tank shape display field 222.

[0179] When a conical bottom tank is selected as the tank shape, after setting the bottom distance Y0 using the bottom distance setting screen 211 and the top distance Y1 using the top distance setting screen 212, and before setting the tank capacity using the capacity setting screen 230, the bottom height setting screen 240 shown in Figure 36 is displayed on the display unit 20.

[0180] The bottom height setting screen 240 includes a level gauge icon 131, a container bottom line 133, a container icon 135, a bottom height setting field 241, and a bottom height arrow 243. In the bottom height setting screen 240, the height of the cone-shaped part of the lower part of the conical bottom tank is set. The distance from the bottom of the conical bottom tank to the boundary between the cone-shaped part and the cylindrical part is the height of the cone-shaped part. Hereinafter, the height of the cone-shaped part may be referred to as the bottom height or the bottom height. The bottom height arrow 243 displayed on the bottom height setting screen 240 indicates that the bottom height is set. For the purpose of explanation, FIG. 36 shows a cone-shaped part boundary line 242 that extends horizontally from the boundary between the cone-shaped part and the cylindrical part of the container icon 135. This cone-shaped part boundary line 242 is not displayed on the bottom height setting screen 240. The bottom height arrow 243 indicates the distance between the container bottom line 133 and the cone-shaped part boundary line 242.

[0181] Candidate values ​​for the bottom height are displayed in the bottom height setting field 241. When the down key 35 and the up key 36 are operated on the bottom height setting screen 240, the numerical value displayed in the bottom height setting field 241 increases or decreases. When the enter key (center key 39) is operated on the bottom height setting screen 240, the numerical value displayed in the bottom height setting field 241 is set as the bottom height (height of the cone-shaped portion) of the container 70. The bottom height is treated as part of the container information regarding the container 70.

[0182] Once the bottom height of the conical bottom tank is set, the capacity setting screen 230 is then displayed on the display unit 20, and the tank capacity is set. The level meter 10 can calculate the relationship between the measured level Y and the volume of the contents 72 in the container 70, based on the set bottom distance Y0, top distance Y1, bottom height, and tank capacity, and on the fact that the tank (container 70) is a conical bottom tank.

[0183] Figure 37 shows a case where the name (option) of the tank shape displayed in the tank shape setting field 221 on the tank shape setting screen 220 is "square pyramidal bottom tank." In Figure 37, an illustration of a square pyramidal bottom tank is shown in the tank shape display field 222. When a square pyramidal bottom tank is selected as the tank shape, the bottom height (height of the conical portion) of the container 70 is set on the bottom height setting screen 240, in the same way as in the case of a conical bottom tank.

[0184] Fig. 38 shows a case where the name (option) of the tank shape displayed in the tank shape setting field 221 on the tank shape setting screen 220 is "inclined-bottom tank." In Fig. 38, an illustration of an inclined-bottom tank is shown in the tank shape display field 222. When an inclined-bottom tank is selected as the tank shape, the bottom height of the container 70 is set on the bottom height setting screen 240, as in the case of a conical bottom tank. Note that the bottom height of an inclined-bottom tank is the height of the inclined portion at the bottom of the inclined-bottom tank.

[0185] FIG. 39 shows a case where the name (option) of the tank shape displayed in the tank shape setting field 221 on the tank shape setting screen 220 is "multi-point correction". When the option of multi-point correction is displayed, a multi-point correction table 225 is displayed instead of the tank shape display field 222. The multi-point correction table 225 is a table showing the setting of correction points determined by a combination of the value of the level Y of the content 72 and the value of the volume of the content 72 corresponding to that value in a tank having a complex shape. In FIG. 39, the fields of the first correction point height 251a, the first correction point volume 251b, the second correction point height 252a, and the second correction point volume 252b are displayed.

[0186] When multi-point correction is selected on the tank shape setting screen 220, after the bottom distance setting screen 211 and the top surface distance setting screen 212, a multi-point correction screen 250 shown in Fig. 40 is displayed on the display unit 20 instead of the capacity setting screen 230. Note that when multi-point correction is used, the shape of the container 70 is complex, but it is preferable to use an existing container icon 135 such as a straight tank as the container icon 135 on the bottom distance setting screen 211 and the top surface distance setting screen 212.

[0187] The number 250N of multi-point correction points and the height and volume of each correction point are displayed on the multi-point correction screen 250. A first correction point height 251a, a first correction point volume 251b, and a second correction point height 252a are displayed in Fig. 40. By operating the down key 35 and the up key 36 to scroll the multi-point correction screen 250, other values ​​such as a second correction point volume 252b not shown in Fig. 40 are also displayed.

[0188] When the number of multi-point correction points 250N is selected on the multi-point correction screen 250, the display unit 20 transitions to a number of correction points setting screen (not shown). On the number of correction points setting screen, the number of correction points is set. The number of correction points may be selected from a number of predetermined options (for example, from 2 to 32).

[0189] When the height or volume of each correction point, such as the first correction point height 251a or the first correction point volume 251b, is selected on the multi-point correction screen 250, the display unit 20 transitions to a screen (not shown) for setting the height or volume of each correction point. On the screen for setting the height of the correction point, the value of the height of the correction point is set within the range of the height of the container 70. On the screen for setting the volume of the correction point, the value of the volume of the contents 72 when the level Y of the contents 72 reaches the height of the correction point is set. Based on the settings of these correction points, the level meter 10 can calculate the relationship between the measured level Y and the volume of the contents 72 in the container 70. Note that, after the settings of each correction point are made on the multi-point correction screen 250, when the display of the display unit 20 is returned to the tank shape setting screen 220, the numerical values ​​of each correction point that have been set may be displayed on the multi-point correction table 225.

[0190] FIG. 41 shows an example of a tank shape (shape of a container 70) that supports multi-point correction. FIG. 41 shows a schematic diagram of a cross section of a container 70. The container 70 has a shape in which the height of the upper end is the first correction point height 251a, and the left and right width increases downward to the second correction point height 252a. Then, the left and right width decreases between the second correction point height 252a and the container bottom line 133. In such a container 70, the value of the level Y and the volume of the contained item 72 are not simply proportional to each other.

[0191] Here, if the volume of the contained contents 72 corresponding to the first correction point height 251a (first correction point volume 251b) and the volume of the contained contents 72 corresponding to the second correction point height 252a (second correction point volume 252b) are set, the level meter 10 can calculate the volume of the contained contents 72 at any level Y by assuming that the left-right width of the container 70 changes linearly between the correction points. Even if the container 70 has a more complicated shape, the level meter 10 can calculate a value equivalent to the actual volume of the contained contents 72 for any level Y if a large number of correction points (for example, 32 points) are set.

[0192] When the settings on the capacity setting screen 230 or the multi-point correction screen 250 are completed, the scaling setting 200 is completed. Thereafter, the display contents on the display unit 20 change to each threshold setting screen (such as the first threshold setting screen 310), an indicator light pattern setting screen 380, and a setup completion confirmation screen 390, completing the initial setting 100 of the level meter 10. After completing the initial setting 100, the level meter 10 transitions to the measurement mode 500 (FIG. 7).

[0193] 42 shows an example of the display section 20 in the measurement mode 500. On the display section 20 in the measurement mode 500, a bar display 22, a color gauge 24, an auxiliary display section 26, and an output status display section 27 are displayed.

[0194] The length of the bar display 22 expands or contracts according to the value of the level Y measured by the level meter 10 (determined by the level determination unit 88). A bar arrow 22a is displayed at the top end of the bar display 22. The bar display 22 expands or contracts within a container icon 25 that resembles a container 70. The container icon 25 displays a scale along the length of the container icon 25 that divides the length of the container icon 25 evenly (10 divisions in FIG. 42). By checking the position of the bar arrow 22a and the scale of the container icon 25, the user can easily visually grasp what percentage of the entire container 70 the current level Y is (the relative position to the container 70).

[0195] The color gauge 24 is displayed alongside a container icon 25 including a bar display 22. The length of the color gauge 24 is aligned with the extension direction of the bar display 22. The color gauge 24 also includes multiple sections (five in FIG. 42), which are arranged along the extension direction of the bar display 22. The bar arrow 22a points to a position within the color gauge 24 that corresponds to the length of the bar display 22.

[0196] The color gauge 24 is color-coded for each section. The indicator light 52 of the level meter 10 lights up in the same color as the section indicated by the bar arrow 22a. The color of the indicator light 52 does not necessarily have to be exactly the same as the color of the section indicated by the bar arrow 22a, as long as the illuminated state of the indicator light 52 corresponds to the color of the section indicated by the bar arrow 22a. For example, when the section indicated by the bar arrow 22a is a color corresponding to an off state (e.g., black), the indicator light 52 may be off.

[0197] The color-coding pattern of the color gauge 24 matches the color-coding pattern of the virtual color gauge 385 when the indicator light pattern is set on the indicator light pattern setting screen 380 (FIG. 22). Note that, depending on the indicator light pattern, the color gauge 24 may not be color-coded, with all sections being the same color or sections being turned off. Note that even if the gauge is not color-coded, the sections are still divided by displaying the borders between the sections, etc.

[0198] The color gauge 24 indicates the relative position of the threshold (level setting value) with respect to the container 70. The position of the boundary of each section of the color gauge 24 is determined based on the container information and threshold set in the initial setting 100. Specifically, the magnitude of the difference between the thresholds corresponds to the size of each section, and the ratio of each threshold to the height of the container 70 (one piece of container information) corresponds to the position of the boundary of each section with respect to the overall length of the container icon 25. By checking the container icon 25 and the boundaries of each section of the color gauge 24, the user can easily visually grasp the relative position of the set threshold (level setting value) with respect to the container 70.

[0199] As described above, on the display unit 20 in the measurement mode 500, the relative position of the level setting value with respect to the container 70 is displayed based on the level Y determined by the level determination unit 88, the container information, and the level setting value, along with a bar display 22 whose length expands or contracts according to the value of the level Y.

[0200] Auxiliary display section 26 displays a numerical value based on level Y determined (measured) by level determination section 88. In Fig. 42, the numerical value (height) of measured level Y is displayed in mm. Note that when scaling setting 200 is performed in initial setting 100, the display format of auxiliary display section 26 is based on the settings on display value setting screen 201 (Fig. 26).

[0201] For example, when L (liter) is selected as the unit of the display value, the auxiliary display section 26 displays the volume of the contents 72 in the container 70 in units of L. In this case, the volume of the contents 72 is calculated based on the measured level Y and the container information set in the initial setting 100.

[0202] In addition, the display format of the auxiliary display unit 26 may be changeable in response to a user operation in the measurement mode 500. For example, when the user operates the right key 37 or the left key 38 in the measurement mode 500, the display format of the auxiliary display unit 26 may be switched to height (mm), volume (L), percentage of the full amount (%), or the like.

[0203] The output status display section 27 displays the status of the signal line in the external output terminal 12D, whose output changes depending on the relationship between the measured level Y and the threshold (level setting value). How the status of the signal line changes depending on the relationship between the level Y and the threshold is determined by the setting contents in the output logic setting screen 315 (FIG. 20) for each threshold. For example, when "normal open" is selected in the output logic setting screen 315 for all four thresholds, when the level Y exceeds the threshold, the signal of the signal line corresponding to that threshold becomes valid. In FIG. 42, the bar arrow 22a points to the fourth section from the top of the color gauge 24. That is, the value of the level Y exceeds the fourth threshold from the top. On the other hand, the value of the level Y is smaller than the first, second, and third thresholds from the top. In the output status display section 27 in FIG. 42, only the number "4" is highlighted (blacked out), and the other numbers are not highlighted (white out). This indicates that only the signal line corresponding to the fourth threshold is enabled (outputs a signal).

[0204] 7, the display of the display unit 20 can transition between a display screen in the measurement mode 500 and a menu screen 600. For example, when the user operates the menu key 32 in the measurement mode 500, the display of the display unit 20 transitions to the menu screen 600 shown in FIG.

[0205] The menu screen 600 includes an option for transitioning to a display screen for the measurement mode 500 (a screen that displays the "current value" of the level Y). The menu screen 600 also includes options for transitioning to individual setting screens, such as a container setting screen 610, a setting value change screen 620, and a various setting screen 630. In addition to these, the menu screen 600 in FIG. 43 also includes an option for transitioning to a screen for an adjustment function 640. On the screen for the adjustment function 640, a determination is made as to whether the installation state of the level meter 10 is appropriate based on the stability of the reflected signal Rx received by the receiving circuit 43R, and various settings are adjusted according to the determination result.

[0206] When an option for transitioning to a container setting screen 610 is selected on the menu screen 600 (the character string "Basic installation settings" in FIG. 43), the display unit 20 transitions to the container setting screen 610, not shown. On the container setting screen 610, the setting unit 61 performs a resetting process for changing the container information already set in the container setting 210 (FIGS. 9 and 10) included in the operation setting 300 or the scaling setting 200 during the initial setting 100. In the container information resetting process, a screen including a numerical value setting field, a level gauge icon 131, a container icon 135, etc., is displayed on the display unit 20, such as the bottom distance setting screen 211 (FIG. 17) and the top surface distance setting screen 212 (FIG. 18) used in the initial setting 100.

[0207] When the re-setting process of the container information is performed, it is preferable that the relative position of the level Y with respect to the container 70 or the value of the level Y is displayed for the current level Y determined (measured) by the level determination unit 88. For example, in addition to the display of the bottom distance setting screen 211 and the top surface distance setting screen 212, a bar display 22 indicating the relative position of the level Y with respect to the container 70 may be displayed in the container icon 135, similar to the display unit 20 in the measurement mode 500. The measured value of the current level Y may be displayed as a character string (for example, a character string such as "current value 1500 mm"). The bar display 22 indicating the relative position of the current level Y and a character string indicating a numerical value may be displayed together. During the re-setting process, the bar display 22 and the character string indicating a numerical value displayed on the display unit 20 may change in real time according to the measured value. In addition to the bottom distance Y0 and the top surface distance Y1, the container setting screen 610 may also set general container information related to the container 70, such as the tank shape.

[0208] In the resetting process, the values ​​of the already set container information (bottom distance Y0, top distance Y1, etc.) may also be displayed on the display unit 20. In the resetting process of the container information, the relative position of the current level Y with respect to the container 70, the value of the level Y, and the values ​​of the already set container information are displayed on the display unit 20, so that the user can set the container information to be reset while being aware of the magnitude relationship between the current value of level Y and the already set container information.

[0209] When an option for transitioning to a setting value change screen 620 (the character string "Change Setting Value" in FIG. 43) is selected on the menu screen 600, the display unit 20 transitions to the setting value change screen 620 (not shown). On the setting value change screen 620, the setting unit 61 performs a resetting process for changing the level setting value (threshold value) that has already been set in the operation setting 300 (FIG. 9) during the initial setting 100. In the level setting value resetting process, a screen including a numerical value setting field, a level gauge icon 131, a container icon 135, an identifier for each threshold value, and the like is displayed on the display unit 20, like the first threshold setting screen 310 (FIG. 19) and the second threshold setting screen 320 (FIG. 20) used in the initial setting 100.

[0210] When the level setting value is reset, it is preferable that the display unit 20 displays the relative position of the level Y with respect to the container 70 (such as the bar display 22) or the value of the level Y (such as a character string showing a numerical value). It is also preferable that the value of the threshold that has already been set is also displayed on the display unit 20. By displaying this information, the user can set the level setting value to be reset while being aware of the magnitude relationship between the current value of the level Y and the level setting value that has already been set. Note that, when there are multiple thresholds to be reset, it is preferable that only the display related to the threshold to be set is highlighted. For example, it is preferable that only the identifier and threshold line of the threshold to be set are displayed brightly, and the identifiers and threshold lines of thresholds other than the threshold to be set are displayed grayed out.

[0211] When an option for transitioning to a various setting screen 630 (the character string "Settings" in FIG. 43) is selected on the menu screen 600, the display unit 20 transitions to the various setting screen 630 shown in FIG. 44. The various setting screen 630 includes options for transitioning to individual setting screens such as an input / output setting screen 631, a detection setting screen 632, and a system setting screen 633. In addition to these, the various setting screen 630 in FIG. 44 also includes an option for performing initialization 634 and an option for performing simulation 635. When the option for performing initialization 634 is selected, various setting values ​​such as container information and thresholds are reset to predetermined initial setting values. When the option for performing simulation 635 is selected, a simulation is performed to check whether the level gauge 10 operates according to the settings while virtually changing the value of the level Y measured by the level gauge 10.

[0212] When an option for the input / output setting screen 631 is selected on the various setting screen 630, the display unit 20 transitions to an input / output setting screen 631 shown in Fig. 45. On the input / output setting screen 631 transitioned from the various setting screen 630, the characteristics of the external input terminal 12C and the external output terminal 12D in the connection unit 12 of the level meter 10 are set.

[0213] The input / output setting screen 631 in Fig. 45 includes an option for setting the value of the number of control outputs and an option for setting the characteristics of each terminal (signal line) of the connection unit 12. The value of the number of control outputs indicates how many of the multiple signal lines included in the connection unit 12 are used as external output terminals 12D for outputting signals to the outside in the current measurement. This value of the number of control outputs becomes the number of thresholds related to level Y. When the option for setting the value of the number of control outputs is selected, the display unit 20 displays multiple options indicating the number of signal lines that can be used as external output terminals 12D, and allows the user to select one of the options.

[0214] When an option for setting the characteristics of each terminal (such as a character string "IO1: control output") is selected, the display unit 20 transitions to a terminal characteristics setting screen (not shown). In the terminal characteristics setting screen, the threshold value (level setting value) and output logic (normally open or normally closed) corresponding to each terminal (signal line) are set.

[0215] The input / output setting screen 631 may include options such as whether to enable an analog output terminal that outputs an analog value (e.g., a current value of 4 to 20 mA), whether to use any terminal as a terminal for serial communication, whether to enable the external input terminal 12C, and whether the characteristics of the transistors used for the external output and external input of the level meter 10 are PNP type or NPN type. For example, when the external input terminal 12C is enabled, the level meter 10 becomes able to receive setting information such as container information and a level setting value from outside the level meter 10 via the connection unit 12.

[0216] When an option of the detection setting screen 632 is selected on the various setting screen 630 of FIG. 44, the display unit 20 transitions to a detection setting screen 632 (not shown). On the detection setting screen 632, the measurement conditions (detection settings) of the level Y by the level meter 10 are set. The measurement conditions of the level Y are, for example, container information such as the bottom distance Y0 and the top surface distance Y1. An example of a measurement condition other than the container information is a mask setting for ignoring a reflected signal Rx from a specific position in the container 70 in a specific measurement environment. An example of a measurement environment in which a mask setting is required is a case in which there is an element (for example, a device such as a stirrer provided in the container 70) that reflects the measurement signal Tx in the container 70 other than the interface 74 of the contents 72. When a mask setting is required, the setting unit 61 sets a level setting value for the mask setting on the detection setting screen 632. Then, when the level determination unit 88 determines that the reflected signal Rx received by the receiving circuit 43R is reflected at a position corresponding to the level setting value for the mask setting, the level determination unit 88 ignores the reflected signal Rx.

[0217] When an option for the system setting screen 633 is selected on the various setting screen 630, the display unit 20 transitions to a system setting screen 633 (not shown). On the system setting screen 633, a reset process of setting items that are not reset on the container setting screen 610, the input / output setting screen 631, and the detection setting screen 632 may be performed. For example, on the system setting screen 633, a reset process of the indicator light pattern set on the indicator light pattern setting screen 380 (FIG. 23), the display language set on the language setting screen 110 (FIG. 11), and the like may be performed. Also, on the system setting screen 633, a setting item that is not set on the initial setting 100, such as screen brightness, may be set.

[0218] Next, another example of the level gauge 10 will be described with reference to Fig. 46 and Fig. 47. Fig. 46 is a perspective view showing another example of the level gauge 10. Fig. 47 is a cross-sectional view of another example of the level gauge 10. In Fig. 46 and Fig. 47, components having the same functions as those in the level gauge 10 in Figs. 1 and 2 are denoted by the same reference characters as in Figs. 1 and 2, and descriptions thereof will not be repeated unless necessary.

[0219] In the level gauge 10 in Figures 46 and 47, the housing 15 has a generally cylindrical shape extending in the longitudinal direction A. The housing 15 in Figures 46 and 47 is functionally an integrated unit of the base portion 15a and the terminal portion 21 in Figures 1 and 2 of the level gauge 10. The level gauge 10 in Figures 46 and 47 has smaller dimensions than the level gauge 10 in Figures 1 and 2.

[0220] In the level meter 10 of Figs. 46 and 47, the connection part 12 is provided on the upper side of the housing 15. The display part 20 is disposed on the outer peripheral surface of the housing 15 that extends along the longitudinal direction A. The indicator light 52 is disposed between the connection part 12 and the display part 20 so as to surround the lower side (base) of the connection part 12. As shown in Fig. 47, the status LED 50 and the transparent window 53 of the indicator light 52 are disposed above the display part 20. The operation part 30 is disposed adjacent to the display part 20 and includes a menu key 32 and a direction key 33 that are aligned along the longitudinal direction A. The direction key 33 also has an up key 36 and a down key 35 that are aligned along the longitudinal direction A.

[0221] Various information is displayed on the display unit 20 of the level meter 10 in Figures 46 and 47, similar to the display unit 20 in the level meter 10 in Figures 1 and 2. However, since the display unit 20 in Figures 46 and 47 is smaller than the display unit 20 in Figures 1 and 2, the displayed content may be simplified.

[0222] Hereinafter, some of the screens displayed on the display unit 20 of the level gauge 10 in Figs. 46 and 47 will be described as examples of individual screens in the level gauge 10 in Figs. 1 and 2. Fig. 48 shows another example of the bottom distance setting screen 211. This bottom distance setting screen 211 is not significantly different from the bottom distance setting screen 211 (Fig. 17) in the level gauge 10 in Figs. 1 and 2, but due to screen space, the guide displays "OK" and "RETURN" are not displayed at the bottom of the screen. In the level gauge 10 in Figs. 46 and 47, it is preferable that the menu key 32 is operated to make a decision. In addition, it is preferable that some screens have an option to return to a screen where the setting has already been completed. In addition, a function similar to "RETURN" may be realized by a combination of keys included in the operation unit 30. For example, when the menu key 32 and the up key 36 are operated simultaneously, an operation similar to that when the key (left key 38) corresponding to "RETURN" in the level gauge 10 in Figs. 1 and 2 is operated (the display content of the display unit 20 returns to the previous screen) is performed.

[0223] Fig. 49 shows another example of the second threshold setting screen 320. Compared to the second threshold setting screen 320 (Fig. 20) in the level gauge 10 in Figs. 1 and 2, the display is simplified by not displaying the normally open icon 324a, the normally closed icon 324b, the first threshold identifier 314, and the value of the first threshold that has already been set. However, the first threshold line 313 is displayed in a faint manner (e.g., grayed out). The numerical value of the height of the container 70 (here, 1500) is also displayed.

[0224] 50 shows another example of the second threshold output logic setting screen 325. In the second threshold output logic setting screen 325, the first threshold identifier 314, which was omitted in the second threshold setting screen 320, is displayed dimly (e.g., grayed out). Note that the ON icon 316a and the OFF icon 316b are displayed next to the container icon 135, not next to the output logic setting field 316, due to display space limitations.

[0225] Figure 51 shows another example of the indicator light pattern setting screen 380. Compared to the indicator light pattern setting screen 380 (Figure 22) for the level gauge 10 in Figures 1 and 2, the display is simplified by not displaying the identifiers of each threshold value. Note that, since the indicator light 52 is placed at the top of the level gauge 10 in Figures 46 and 47, the indicator light icon 382 is displayed at the top of the level gauge icon 131 in Figure 51.

[0226] 51 also displays an animation image showing the change in the operation of the level meter 10 in accordance with an increase or decrease in the level Y. That is, while the indicator light pattern setting screen 380 is displayed, the virtual bar display 383 repeatedly expands and contracts, and as the virtual bar display 383 expands and contracts, the state of the indicator light icon 382 and the state of the actual indicator light 52 change.

[0227] Fig. 52 shows another example of the setup completion confirmation screen 390. In the setup completion confirmation screen 390, a first threshold identifier 314 and a second threshold identifier 324 that are reduced in size are displayed at the boundary positions of each section of the virtual color gauge 385. Compared to the setup completion confirmation screen 390 (Fig. 25) for the level gauge 10 in Figs. 1 and 2, the display is simplified by not displaying the numerical values ​​of each threshold. Also in the setup completion confirmation screen 390 in Fig. 52, an animation image is displayed showing the change in the operation of the level gauge 10 as the level Y increases or decreases, by repeatedly expanding and contracting the virtual bar display 383.

[0228] Next, with reference to Fig. 53, a further example of the level gauge 10 will be described. Fig. 53 is a perspective view showing a further example of the level gauge 10. In Fig. 53, components having the same functions as those in the level gauge 10 in Figs. 1 and 46 are denoted by the same reference numerals as in Figs. 1 and 46, and descriptions thereof will not be repeated unless necessary.

[0229] 53, the level meter 10 includes a sensor unit 16 and a remote controller 55 capable of communicating with the sensor unit 16 at a position remote from the sensor unit 16. The sensor unit 16 and the remote controller 55 are connected by a communication cable 11. In the level meter 10 in FIG. 53, only the sensor unit 16 is attached to a container 70 that contains an item 72, and the remote controller 55 communicates with the sensor unit 16 at a position remote from the container 70.

[0230] As shown in FIG. 53, the sensor unit 16 has a generally cylindrical shape. The indicator light 52 is provided on the upper part of the sensor unit 16. The remote control device 55 corresponds to the housing 15 in the level meter 10 of FIG. 1 and FIG. 46, and includes a display unit 20 that displays a value according to the measured level Y. The display unit 20 can display a bar display 22 and a color gauge 24. The remote control device 55 also includes an operation unit 30 that allows the user to operate the operation of the level meter 10. The remote control device 55 also includes a connection unit 12 that serves as a connection terminal for connecting to an external device. The remote control device 55 also includes a remote indicator light 54. The remote indicator light 54 lights up in the same lighting state as the indicator light 52 of the sensor unit 16.

[0231] Various information is displayed on the display unit 20 of the level gauge 10 in Fig. 53, similar to the display unit 20 in the level gauge 10 in Fig. 1 and Fig. 46. The information shown to the user by the display unit 20 in Fig. 53 is the same as that in Fig. 1 and Fig. 46. The display content by the display unit 20 in Fig. 53 may be simplified depending on the size of the display unit 20. [Explanation of symbols]

[0232] 10 Level gauge 15. Cabinet 15a Pedestal 16 Sensor section 17 Mounting part 19 Rotation mechanism 20 Display section 21 Terminal Unit 22 Bar Display 24 Color Gauge 26 Auxiliary display 30 Control section 41 Sensor IC 43 Transmitter / receiver 43T Transmitter circuit 43R Receiver circuit 52 Indicator light 61 Setting section 63 Memory section 64 Arithmetic section 65 Input section 66 Output section 70 containers 72 Contents 74 Interface 88 Level Determination Department 131 Level Gauge Icon 135 container icon 382 indicator light icon 383 Virtual Bar Display 314a normally open icon 314b normally closed icon

Claims

1. A level meter that is installed in an upper portion of a container toward a bottom surface of the container to measure a level of an object contained in the container, A transceiver unit including a transmission circuit for transmitting a measurement signal for measuring the level, and a reception circuit for receiving a reflected signal resulting from the measurement signal being reflected by the contained object; a level determination unit that determines the level based on the reflected signal received by the receiving circuit and container information related to the container; a setting unit for sequentially setting the container information and a plurality of level setting values ​​related to the level determined by the level determination unit; a display unit that displays a relative position of the level setting value with respect to the container based on the level determined by the level determination unit, the container information, and the level setting value, together with a bar display whose length expands or contracts according to the value of the level determined by the level determination unit; A level meter equipped with

2. 2. A level gauge according to claim 1, wherein the display unit includes a plurality of compartments arranged along the extension direction of the bar display, and displays a gauge in which the positions of the boundaries of the compartments are determined based on the container information and the level setting value, thereby displaying the relative position of the level setting value with respect to the container.

3. the setting unit sets at least a height of the container or a distance from the level meter to a bottom surface of the container as the container information related to the container; The level meter according to claim 1 , wherein the display unit displays a relative position of the level setting value with respect to the container, and also displays a value of a height of the container or a distance from the level meter to a bottom surface of the container.

4. The level meter of claim 1 , wherein the display unit displays a container icon indicating the container and a level meter icon indicating the level meter when the container information and the level setting value are set by the setting unit.

5. 2. The level meter of claim 1 , wherein after a plurality of level setting values ​​are set by the setting unit, the display unit displays the numerical values ​​of each of the set level setting values ​​together with the relative positions of each of the level setting values ​​with respect to the container.

6. 2. The level meter of claim 1, wherein the display unit displays a level setting value identifier individually assigned to each of the plurality of level setting values ​​set by the setting unit, together with a numerical value of the level setting value corresponding to the level setting value identifier.

7. The level meter of claim 1 , wherein the display unit displays an animation image showing a change in the operation of the level meter in accordance with an increase or decrease in the level.

8. The device further includes an indicator lamp whose lighting state changes according to a relationship between the level determined by the level determination unit and the level setting value set by the setting unit, 2. The level meter of claim 1, wherein the display unit displays an animated image including a virtual bar display virtually showing the expansion and contraction of the bar display as the level increases or decreases, and an indicator light icon virtually showing a change in the lighting state of the indicator light as the level increases or decreases.

9. 9. The level gauge of claim 8, wherein an actual lighting state of said indicator light changes in conjunction with a change in a lighting state of said indicator light icon accompanying expansion or contraction of said virtual bar display.

10. The level meter according to claim 8 , wherein the setting unit sets a change pattern of the illumination state of the indicator lamp in response to an increase or decrease in the level.

11. 2. The level meter of claim 1, wherein the display unit includes a two-wire reflective color liquid crystal display that transmits and receives power and communicates data via two power lines.

12. The setting unit is capable of performing a resetting process for changing the container information and the level setting value that have already been set, The level meter of claim 1 , wherein the display unit displays, when the resetting process is performed by the setting unit, the relative position of the level with respect to the container or the value of the current level determined by the level determination unit.

13. when the level set value is set by the setting unit, the display unit displays a normally open icon indicating that an operation of the level meter will change when the level determined by the level determination unit exceeds the level set value, and a normally closed icon indicating that an operation of the level meter will change when the level determined by the level determination unit falls below the level set value, On the display unit, the normally open icon is disposed above the normally closed icon, 2. The level meter of claim 1, wherein the setting unit determines whether the operation of the level meter will change when the level exceeds the level setting value or when the level falls below the level setting value, depending on whether the normally open icon or the normally closed icon is selected.

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