Resistance acquisition and output device and method and central air-conditioning system with resistance acquisition and output device

Abstract

The invention discloses a resistance acquisition and output device and method and a central air conditioning system with the resistance acquisition and output device, the resistance acquisition and output device comprises an input relay, an acquisition unit, a communication unit, a control unit, a resistance simulator, an output relay and a far end, the input relay is electrically connected with the acquisition unit and the output relay, and the acquisition unit is electrically connected with the control unit. The control unit is electrically connected with one end of the resistance simulator and one end of the communication unit, the other end of the communication unit is connected with a far end, and the other end of the resistance simulator is electrically connected with the output relay. The input relay is provided with an input terminal, the input terminal is respectively connected with the output relay and the acquisition unit or disconnected from the output relay and the acquisition unit, the output relay is provided with an output terminal, and the output terminal is respectively connected with the input relay and the resistance simulator or disconnected from the input relay and the resistance simulator. The method has the characteristics that the resistance values of one or more types of resistance type sensors can be acquired, and the acquired resistance values are converted and then restored to an original system.

Description

Technical Field

[0001] The present invention relates to the technical field of resistance acquisition and output, and in particular to a resistance acquisition and output device and method, and a central air-conditioning system having the same. Background Art

[0002] Many existing automated control systems rely on resistive sensors to measure environmental physical quantities, using these changes as the basis for control strategy matching and command issuance. Resistive sensors are based on the impedance characteristics of semiconductors. The output resistance of semiconductors varies with environmental conditions, and automated equipment triggers its control logic based on these changes.

[0003] In a large building complex, a wide variety of devices utilize resistive sensors, including variable-frequency water pumps, temperature switches, and illumination regulators. Variable-frequency water pumps are controlled by frequency converters, which control the pump's speed based on changes in the water pressure sensor. Temperature switches use circuits based on changes in the temperature sensor to control the on / off state of the circuit. Illumination regulators control the brightness of light bulbs based on changes in the illumination sensor. While these devices often have certain logical relationships, they often come from different manufacturers. Besides the repeated placement of sensors in the same area, users struggle to ensure that these devices work together according to a previously discovered logic. Furthermore, it's difficult to uniformly display the physical quantities represented by these sensors and manage diverse systems.

[0004] For example, Chinese invention patent publication number CN108548306A discloses a temperature acquisition device and cooling and heat control system for a central air conditioner. This device requires repeated arrangement of temperature probes on the pipe wall. In actual implementation, since probes with the same specifications and parameters as the original manufacturer are difficult to purchase, it is difficult to ensure that the temperature data collected by this probe is consistent with the data collected by the original probe of the air conditioner, which will cause unpredictable deviations during restoration. Summary of the Invention

[0005] The purpose of the present invention is to address the defects of the existing technology and provide a multi-channel resistance acquisition and output device, method and central air-conditioning system having the same, which can simultaneously acquire multiple resistance data and restore them separately. The working mode of the device can be bypass, acquisition or special mode.

[0006] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0007] A resistance acquisition and output device of the present invention comprises an input relay, an acquisition unit, a communication unit, a control unit, a resistance simulator, an output relay and a remote end, wherein the input relay is electrically connected to the acquisition unit and the output relay respectively, the acquisition unit is electrically connected to the control unit, the control unit is electrically connected to one end of the resistance simulator and the communication unit respectively, the other end of the communication unit is connected to the remote end, and the other end of the resistance simulator is electrically connected to the output relay; the input relay is provided with an input terminal, and the input terminal is in two working states of being connected or disconnected with the output relay and the acquisition unit respectively, and the output relay is provided with an output terminal, and the output terminal is electrically connected to the input relay respectively. The device and the resistance simulator are in two working states: on or off; the remote end sends a signal to the communication unit, and the communication unit transmits the signal to the control unit. The control unit controls the switches of the input relay and the output relay according to the signal. When the input relay is closed, the input terminal of the corresponding channel is directly electrically connected to the output relay and no data is collected; when the input relay is opened, the input terminal of the corresponding channel is directly electrically connected to the collection unit to realize resistance collection; when the output relay is closed, the output terminal of the corresponding channel is directly electrically connected to the input relay and no data is restored; when the output relay is opened, the output terminal of the corresponding channel is directly electrically connected to the resistance simulator to realize resistance restoration output.

[0008] Furthermore, the number of the input relays, the resistance simulator, and the output relays is set accordingly, and the number of the input relays, the resistance simulator, and the output relays is at least two. The two or more input relays are respectively connected in parallel to the acquisition unit, and the two or more resistance simulators and output relays are connected in series in pairs and then respectively connected in parallel to the control unit. This enables simultaneous acquisition of multiple channels of resistance data and their respective restoration.

[0009] Furthermore, the acquisition unit is a voltage acquisition device and / or a resistance acquisition device. The voltage acquisition device calculates the resistance value from the acquired voltage using a voltage divider method. Using a voltage acquisition device can improve the accuracy of the corresponding value acquired. The resistance acquisition device uses a bridge method to equalize the voltage across the bridge, balancing the bridge and thereby determining the resistance value. Using a resistance acquisition unit can ensure acquisition accuracy while reducing the cost of the acquisition circuit.

[0010] Furthermore, the voltage acquisition device is an analog-to-digital converter, and the resistance acquisition device includes an operational amplifier or a comparator. The resistance acquisition device is a common circuit composed of a digital resistor and an operational amplifier or an operational comparator.

[0011] Furthermore, the control unit is a single chip microcomputer, which is an integrated circuit chip with high reliability, strong processing function, high speed, low voltage, low power consumption, strong control function and strong environmental adaptability.

[0012] Furthermore, the communication unit is a wired communication device or a wireless communication device. The communication unit can transmit information to the remote end in a timely manner, and at the same time, the remote end can feed back the information to the communication unit.

[0013] Furthermore, the wired communication device is any one of a 485 communication module, an RS232 communication module, an Ethernet communication module, and an optical fiber communication module; the wireless communication device is any one of a local area network communication module or a pluggable operator SIM card communication module.

[0014] Furthermore, the resistance simulator is a series-parallel combination of one or more digital resistors.

[0015] As is common knowledge in the field, the connection and data transmission and other action controls between the various components used in this solution, such as the resistance simulator, communication unit, acquisition unit and control unit, belong to mature single-chip microcomputer technology, and these components can be easily purchased from the market and can be used after simple debugging.

[0016] The present invention also provides a resistance acquisition and output method, which uses the resistance acquisition and output device. When each channel in the resistance acquisition and output device is in operation, the operating modes are bypass mode, acquisition mode and special mode.

[0017] Bypass mode: When a channel operates in bypass mode, the input relay and output relay of the channel are both in the closed state, and the resistor connected to the resistance acquisition and output device is directly connected to the original acquisition system without being collected and restored by the resistance acquisition and output device;

[0018] The acquisition mode: When a channel operates in the acquisition mode, the input relay and output relay of the channel are both in the open state, the resistor connected to the resistance acquisition and output device is connected to the acquisition unit through the input relay, the acquisition unit and the control unit collect and calculate the resistance value, and after obtaining the resistance value, the control unit controls the resistance simulator to restore the resistance and output it to the original system through the output relay, and sends the resistance value to the remote end through the communication unit;

[0019] The special mode: When a special situation occurs in a channel working in the acquisition mode, the control unit controls the resistance simulator to restore a normal resistance and outputs it to the original system through the output relay; on the other hand, the abnormal resistance value and alarm information are sent to the remote end through the communication unit.

[0020] Furthermore, the actions of the resistance acquisition and output device in three modes are set by the control unit. When a special situation occurs in a certain channel, the collected resistance value is sent to the remote end. After calculation by the remote end, a resistance value is returned. The control unit then controls the resistance simulator based on this resistance value to restore an equal resistance output to the original system.

[0021] The present invention also provides a central air-conditioning system, which adopts the resistance acquisition and output device, and includes a refrigeration host, a control cabinet, a terminal fan, a chilled water pipe, an outlet water temperature probe, and a return water temperature probe, wherein the outlet water temperature probe and the return water temperature probe are respectively connected to the control cabinet, and the outlet water temperature probe and the return water temperature probe are respectively electrically connected to an input terminal of the resistance acquisition and output device, and two contacts of the control cabinet are respectively connected to an output terminal of the resistance acquisition and output device;

[0022] The data transmission line of the return water temperature probe is as follows: the return water temperature probe is electrically connected to the input terminal I, the input terminal I is correspondingly provided to the input relay I, the input relay I is electrically connected to the acquisition unit, the acquisition unit is electrically connected to the control unit, the control unit is electrically connected to the corresponding output relay I, and the output terminal I on the output relay I is electrically connected to a contact on the control cabinet;

[0023] The data transmission line of the outlet water temperature probe is as follows: the outlet water temperature probe is electrically connected to the input terminal II, the input terminal II is correspondingly provided to the input relay II, the input relay II is electrically connected to the acquisition unit, the acquisition unit is electrically connected to the control unit, the control unit is electrically connected to the corresponding output relay II, and the output terminal II on the output relay II is electrically connected to another contact of the control cabinet;

[0024] The remote end sends a signal to the communication unit, and the communication unit transmits the signal to the control unit. The control unit controls the switches of the input relay I, the input relay II, the output relay I, and the output relay II according to the signal.

[0025] Compared with the prior art, the present invention has the following beneficial technical effects:

[0026] 1. The resistance acquisition and output device of the present invention can acquire the resistance values ​​of one or more types of resistors. After acquisition, the resistance values ​​are restored to one or more original systems corresponding to the original resistors through a resistance simulator. Without knowing the conversion method between the resistance values ​​of the original systems and physical quantities, the device can accurately restore the same resistance. Without affecting the normal operation of the original systems, the acquired resistance values ​​are converted into physical quantities for remote display.

[0027] 2. The combination of the acquisition unit and the control unit in the resistance acquisition and output device of the present invention can better improve the accuracy of acquisition and conversion.

[0028] 3. The resistance acquisition and output device of the present invention can communicate with a remote system, and can be switched into mode by the remote system, and can be remotely controlled to output a specific restored resistance.

[0029] 4. The resistance acquisition and output device of the present invention can remotely record the historical change data of the collected resistance values, and then analyze the mutual influence of the original systems connected to each channel through data analysis. By setting the restoration logic on the control unit, the systems can be made to work together. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0031] Figure 1 Schematic diagram of the structure of the resistance acquisition and output device of Example 1 of the present invention;

[0032] Figure 2 This is a structural diagram of a multi-channel resistance acquisition and output device according to embodiment 3 of the present invention;

[0033] Figure 3 This is a structural diagram of the central air-conditioning system of Example 22 of the present invention.

[0034] Explanation of the accompanying symbols: 1. Input terminal; 2. Input relay; 3. Acquisition unit; 4. Communication unit; 5. Control unit; 6. Resistance simulator; 7. Output relay; 8. Output terminal; 9. Remote end; 21. Refrigeration host; 22. Control cabinet; 23. Terminal fan; 24. Chilled water pipe; 25. Return water temperature probe; 26. Outlet water temperature probe. DETAILED DESCRIPTION

[0035] In order to enable people skilled in the art to better understand the technical solutions of the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings and embodiments. Obviously, the described embodiments are only part of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work should fall within the scope of protection of the present invention.

[0036] Example 1

[0037] like Figure 1As shown, the resistance acquisition and output device of this embodiment 1 includes an input terminal 1, an input relay 2, an output relay 7, an acquisition unit 3, a control unit 5, a resistance simulator 6, a communication unit 4, an output terminal 8 and a remote end 9. The input relay 2 is electrically connected to the acquisition unit 3, the acquisition unit 3 is electrically connected to the control unit 5, the control unit 5 is electrically connected to the resistance simulator 6 and one end of the communication unit 4 respectively, the other end of the communication unit 4 is connected to the remote end 9, the other end of the resistance simulator 6 is electrically connected to the output relay 7, and the input relay 2 is electrically connected to the output relay 7; wherein, the input relay 2 is provided with an input terminal 1, and the input terminal 1 is respectively in two working states of being connected or disconnected with the output relay 7 and the acquisition unit 3; and the output relay 7 is provided with an output terminal 8, and the output terminal set 8 is respectively in two working states of being connected or disconnected with the input relay 2 and the resistance simulator 6.

[0038] At this time, the acquisition unit 3 acquires voltage value information. After the acquisition unit 3 sends the voltage value information to the control unit 5 , the control unit 5 converts the voltage value information into a corresponding resistance value.

[0039] The specific working method is: the remote end 9 sends a specific signal to the communication unit 4, the communication unit 4 transmits the signal to the control unit 5, and the control unit 5 controls the switching of each relay according to the signal (the control circuit of the control unit for the relay is a common circuit, not shown in the figure).

[0040] When the input relay 2 is closed, the input terminal 1 of the corresponding channel is directly electrically connected to the output relay 4; when the input relay 2 is opened, the input terminal 1 of the corresponding channel is directly electrically connected to the acquisition unit 3 to achieve resistance acquisition.

[0041] When the output relay 7 is closed, the output terminal 8 of the corresponding channel is directly electrically connected to the input relay 2; when the output relay 7 is opened, the output terminal 8 of the corresponding channel is directly electrically connected to the resistance simulator 6 to achieve resistance restoration output.

[0042] Example 2

[0043] Compared with Example 1, the difference between this Example 2 is that the number of input relays 2, resistance simulators 6 and output relays 7 corresponds to each other, wherein the number of input relays 2, resistance simulators 6 and output relays 7 are all one.

[0044] At this time, the input relay 2 is connected to the acquisition unit 3 , the acquisition unit 3 is connected to the control unit 5 , the control unit 5 is connected to the resistance simulator 6 , and the resistance simulator 6 is connected to the output relay 7 .

[0045] Example 3

[0046] The difference between this embodiment 3 and embodiment 2 is that: Figure 2 As shown, the number of input relays 2, resistance simulators 6 and output relays 7 is more than two. At this time, more than two input relays 2 are respectively connected to the acquisition unit 3, that is, more than two input relays 2 are connected to the acquisition unit 3 in parallel, and more than two resistance simulators 6 and output relays 7 are connected in series in pairs and then connected in parallel to the control unit 5 respectively.

[0047] Specifically, the number of the input relays 2 , the resistance simulator 6 , and the output relays 7 used is typically 2 to 10.

[0048] The present invention can realize the simultaneous collection of multi-channel resistance data and the respective restoration thereof.

[0049] Example 4

[0050] Compared with any one of Examples 1-3, the difference between this Example 4 is that the acquisition unit 3 is a voltage acquisition device.

[0051] Example 5

[0052] Compared with Example 4, the difference between Example 5 is that the voltage acquisition device is an analog-to-digital converter.

[0053] Among them, the analog-to-digital converter is a converter that converts the analog quantity after comparison with the standard quantity (or reference quantity) into a discrete signal represented by a binary value, referred to as ADC or A / D converter.

[0054] Example 6

[0055] Compared with any one of Examples 1-3, the difference between this Example 6 is that the acquisition unit 3 is a resistance acquisition device.

[0056] Example 7

[0057] Compared with any one of Examples 4-6, the difference between this Example 7 is that the acquisition unit 3 is a combination of a resistance acquisition device and a voltage acquisition device.

[0058] Example 8

[0059] Compared with any one of Examples 1-7, the difference between this Example 8 is that the control unit 5 is a single chip microcomputer.

[0060] Some single-chip microcomputers already have an analog-to-digital converter integrated into their chips. When the acquisition accuracy requirements are not high, the voltage or resistance acquisition device in the single-chip microcomputer can be used to implement the acquisition function. The single-chip microcomputer in this part still has components equivalent to the acquisition unit of the present invention. Therefore, using a single-chip microcomputer alone should not be considered an improvement to this device.

[0061] Example 9

[0062] The difference between this embodiment 9 and any of the embodiments 1-7 is that the communication unit 4 is a wired communication device and is electrically connected to the remote end 9.

[0063] Example 10

[0064] The difference between the present embodiment 10 and the embodiment 9 is that the wired communication device is a 485 communication module, which is a wired module and is commercially available.

[0065] Example 11

[0066] The difference between this embodiment 11 and embodiment 9 is that the wired communication device is an RS232 communication module. The RS232 communication module is a wired module that is commercially available.

[0067] Example 12

[0068] The difference between this embodiment 12 and embodiment 9 is that the wired communication device is an Ethernet communication module. The Ethernet communication module is a wired module that is commercially available.

[0069] Example 13

[0070] The difference between this embodiment 13 and embodiment 9 is that the wired communication device is an optical fiber communication module. The optical fiber communication module is a wired module that is commercially available.

[0071] Example 14

[0072] The difference between this embodiment 14 and embodiment 9 is that the communication unit 4 is a wireless communication device, and the communication unit 4 is connected to the remote end 9 via a signal.

[0073] Example 15

[0074] The difference between this embodiment 15 and embodiment 14 is that the wireless communication device is a local area network communication module. The local area network communication module is a wireless module (such as a WiFi communication module or a LoRa communication module) that is commercially available.

[0075] Example 16

[0076] Compared with Example 14, the difference between this Example 16 is that the wireless communication device is a communication module that can be inserted with an operator's SIM card, and is a communication module that is connected to the operator's network by inserting a SIM card.

[0077] The communication module that can be inserted into the operator's SIM card is a wireless module (such as 2G, 3G, 4G, 5G, NB-LOT communication module), which is commercially available.

[0078] Example 17

[0079] The difference between this embodiment 17 and any one of embodiments 1-16 is that the resistance simulator 6 is a digital rheostat, which is commercially available.

[0080] A digital rheostat, also known as a digitally controlled programmable resistor, is a new CMOS integrated circuit for mixed digital and analog signal processing that replaces traditional mechanical potentiometers (analog potentiometers). A digital rheostat is controlled by a digital input and produces an analog output. Depending on the type of digital rheostat, the tap can output different resistance values. Digital rheostats use digital control to adjust resistance, offering significant advantages such as flexibility, high adjustment accuracy, contactlessness, low noise, resistance to contamination, vibration resistance, interference immunity, compact size, and long life.

[0081] Example 18

[0082] Compared with any one of Examples 1-17, the difference between this Example 18 is that the resistance simulator 6 is a series-parallel combination of multiple digital resistors, and the common number of digital resistors in the resistance simulator 6 is 2 to 5 digital resistors.

[0083] The series combination is: all the adopted digital resistors are connected in series.

[0084] The parallel combination is: connecting the adopted digital resistors in parallel.

[0085] The series-parallel combination is: one digital rheostat is connected in parallel with multiple digital rheostats and then connected in series; or two or more digital rheostats are first connected in series to form a series combination, and then connected in series with the parallel combination of two or more digital rheostats connected in parallel.

[0086] Example 19

[0087] Compared with any of Examples 1-18, the difference between this Example 19 is that the working mode of the resistance acquisition and output device can be a bypass mode, that is, the working mode of each channel of the device is a bypass mode, wherein the resistance acquisition and output device is installed between the required acquisition resistor and the original acquisition system of the resistor.

[0088] The specific operation of the bypass mode is: when a channel works in the bypass mode, the input relay 2 and output relay 7 of the channel are both in the closed state, the input terminal 1 is directly connected to the output terminal 8, and the resistor connected to the resistance acquisition and output device is directly connected to the original acquisition system without being collected and restored by the resistance acquisition and output device.

[0089] Example 20

[0090] Compared to any of Examples 1-18, this embodiment 20 differs in that the resistance acquisition and output device can operate in acquisition mode, that is, each channel of the device operates in acquisition mode. The resistance acquisition and output device is installed between the desired acquisition resistor and the original acquisition system for the resistor. The resistance acquisition and output device acquires the connected resistor and restores the acquired resistance to the original acquisition system.

[0091] The specific work of the acquisition mode is:

[0092] When a channel operates in acquisition mode, the channel's input relay 2 and output relay 7 are both open, and the resistor connected to the device of the present invention is connected to the acquisition unit 3 via the input relay 2. That is, data is transmitted via the input terminal 1 to the input relay 2, then sent to the acquisition unit 3 via the input relay 2, and then sent to the control unit 5. The acquisition unit 3 and the control unit 5 collect and calculate the resistance value in a common manner. After determining the resistance value, the control unit 5 controls the resistance simulator 6 to restore the resistance to the output relay 7, which is then output to the original system via the output relay 7. At the same time, the resistance value (numeric value) is sent to the remote end 9 via the communication unit 4. Without knowing the conversion method between the original system's resistance value and the physical quantity, the same resistance is accurately restored. Without affecting the normal operation of the original system, the collected resistance value is converted into a physical quantity and displayed at the remote end 9.

[0093] Example 21

[0094] Compared to any of Examples 1-18, this embodiment 21 differs in that the resistance acquisition and output device can operate in a special mode, that is, each channel of the device operates in a special mode. The resistance acquisition and output device is installed between the desired acquisition resistor and the original acquisition system for that resistor. The resistance acquisition and output device acquires the connected resistor and restores any resistance value that differs from the acquired value to the original acquisition system.

[0095] The specific work of the special mode is:

[0096] When a channel working in the acquisition mode collects a resistance value within a certain temperature range (for example, a water temperature probe collects a resistance value corresponding to 200 degrees Celsius to 300 degrees Celsius due to its own damage), the control unit 5 controls the resistance simulator 6 to restore the resistance in another temperature range (such as 50 degrees Celsius to 90 degrees Celsius) and outputs it to the original system through the output relay 7. On the other hand, the abnormal resistance value and alarm information are sent to the remote end 9 through the communication unit 4.

[0097] Example 22

[0098] like Figure 3As shown, the central air conditioning system of this embodiment 22 uses the aforementioned resistance acquisition and output device and includes a refrigeration unit 21, a control cabinet 22, a terminal fan 23, a chilled water pipe 24, an outlet water temperature probe 26, and a return water temperature probe 25. The outlet water temperature probe 26 and the return water temperature probe 25 are connected to the control cabinet 22, respectively. The outlet and return water temperatures are obtained by the unit system within the control cabinet 22 by collecting the resistance values ​​of the outlet water temperature probe 26 and the return water temperature probe 25 and converting them.

[0099] In actual situations, it is difficult to obtain the data of the above two temperatures, and it is often necessary to obtain them by opening holes in the pipeline or repeatedly installing temperature probes on the pipe wall.

[0100] like Figure 3 As shown, the outlet water temperature probe 26 and the return water temperature probe 25 of the original central air-conditioning system are electrically connected to an input terminal of the resistance acquisition and output device of the present invention respectively.

[0101] The contacts on the control cabinet 22 that were originally connected to the outlet water temperature probe 26 and the return water temperature probe 25 are each connected to an output terminal of the resistance collection and output device.

[0102] like Figure 3 As shown, the data transmission line of the return water temperature probe 25 is as follows: the return water temperature probe 25 is electrically connected to the input terminal Ⅰ1, the input terminal Ⅰ1 is correspondingly arranged on the input relay Ⅰ2, the input relay Ⅰ2 is electrically connected to the acquisition unit 3, the acquisition unit 3 is electrically connected to the control unit 5, the control unit 5 is electrically connected to the corresponding output relay Ⅰ7, and the output terminal Ⅰ8 on the output relay Ⅰ7 is electrically connected to the contact on the original control cabinet 22 for connecting the return water temperature probe 25.

[0103] like Figure 3 As shown, the data transmission line of the outlet water temperature probe 26 is: the outlet water temperature probe 26 is electrically connected to the input terminal Ⅱ11, the input terminal Ⅱ11 is correspondingly set to the input relay Ⅱ12, the input relay Ⅱ12 is electrically connected to the acquisition unit 3, the acquisition unit 3 is electrically connected to the control unit 5, the control unit 5 is electrically connected to the corresponding output relay Ⅱ17, and the output terminal Ⅱ18 on the output relay Ⅱ17 is electrically connected to the contact on the original control cabinet 22 for connecting the outlet water temperature probe 26.

[0104] The specific working method is as follows: the remote end 9 sends a specific signal to the communication unit 4, the communication unit 4 transmits the signal to the control unit 5, and the control unit 5 controls the switching of each relay (including input relay I2, input relay II12, output relay I7, and output relay II17) according to the signal (the control circuit of the control unit for the relay is a common circuit and is not shown in the figure);

[0105] Bypass mode: When the resistance acquisition and output device receives a command from the remote end 9 to switch to the bypass mode, the input relay I2, input relay II12, output relay I7, and output relay II17 are closed, and the resistance acquisition and output device does not collect the resistance values ​​of the return water temperature probe 25 and the outlet water temperature probe 26. The return water temperature probe 25 is directly electrically connected to the control cabinet 22 of the central air conditioner through the input relay I2 and the output relay I7, and the outlet water temperature probe 26 is directly electrically connected to the control cabinet 22 of the central air conditioner through the input relay II12 and the output relay II17.

[0106] Acquisition mode: When the resistance acquisition and output device receives the command to switch to the acquisition mode from the remote end 9, the input relay I2, input relay II12, output relay I7, and output relay II17 are opened:

[0107] The acquisition unit 3 acquires the resistance (physical quantity) of the return water temperature probe 25 via the input relay I2 and transmits data carrying this resistance information to the control unit 5. The acquisition unit 3 and the control unit 5 acquire and calculate the resistance value in a common manner. After obtaining the resistance value of the return water temperature probe 25, the control unit 5 controls the resistance simulator I6 to restore the resistance value (physical quantity) of the return water temperature probe 25 and transmits this resistance value to the output relay I7. The output relay I7 outputs this resistance value to the original system in the control cabinet 22 via the output terminal I8. Furthermore, the resistance value (numerical value) of the return water temperature probe 25 is transmitted to the remote end 9 via the communication unit 4.

[0108] The acquisition unit 3 acquires the resistance (physical quantity) of the outlet water temperature probe 26 via the input relay I 12 and transmits data carrying this resistance information to the control unit 5. The acquisition unit 3 and the control unit 5 acquire and calculate the resistance value in a common manner. After the control unit 5 obtains the resistance value of the outlet water temperature probe 26, it controls the resistance simulator I 16 to restore the resistance value (physical quantity) of the outlet water temperature probe 26 and transmits this resistance value to the output relay I 17. The output relay I 17 outputs this resistance value to the original system in the control cabinet 22 via the output terminal I 18. Furthermore, the resistance value (numerical value) of the outlet water temperature probe 26 is transmitted to the remote end 9 via the communication unit 4.

[0109] Special mode: When the resistance acquisition and output device working in the acquisition mode detects an abnormality in a certain channel (such as damage to the return water temperature probe 25 or the outlet water temperature probe 26), the control unit 5 controls the corresponding resistance simulator to restore a specific resistance value (such as corresponding to 25°C) and outputs it to the original system of the control cabinet 22 through the output relay correspondingly connected to the resistance simulator. On the other hand, the abnormal resistance value and alarm information are sent to the remote end 9 through the communication unit 4.

[0110] It should be noted that the restored resistance of the resistance acquisition and output device in the special mode can be controlled by the control unit 5 and the remote end 9. For example, when a channel on the resistance acquisition and output device acquires a resistance value (assuming value 1) corresponding to the temperature at that time (such as abnormal temperature: 200°C), the collected resistance value (value 1) can be sent to the remote end 9. After calculation by the remote end 9, a resistance value (value 2) is returned. The control unit 5 then controls the corresponding resistance simulator based on this resistance value to restore a resistance equal to value 2 and output it to the original system.

[0111] The embodiments described above are merely descriptions of preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Without departing from the spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by persons skilled in the art should fall within the scope of protection defined by the claims of the present invention.

Claims

1. A resistance acquisition and output device, characterized in that: The invention comprises an input relay (2), an acquisition unit (3), a communication unit (4), a control unit (5), a resistance simulator (6), an output relay (7) and a remote end (9), wherein the input relay (2) is electrically connected to the acquisition unit (3) and the output relay (7), respectively, the acquisition unit (3) is electrically connected to the control unit (5), the control unit (5) is electrically connected to one end of the resistance simulator (6) and the communication unit (4), respectively, the other end of the communication unit (4) is connected to the remote end (9), and the other end of the resistance simulator (6) is electrically connected to the output relay (7); the input relay (2) is provided with an input terminal (1), and the input terminal (1) is in two working states of being connected or disconnected with the output relay (7) and the acquisition unit (3); the output relay (7) is provided with an output terminal (8), and the output terminal (8) is electrically connected to the input relay (1). The device (2) and the resistance simulator (6) are in two working states: connected or disconnected; the remote end (9) sends a signal to the communication unit (4), the communication unit (4) transmits the signal to the control unit (5), and the control unit (5) controls the switches of the input relay (2) and the output relay (7) according to the signal. When the input relay (2) is closed, the input terminal (1) of the corresponding channel is directly electrically connected to the output relay (7) and no data is collected; when the input relay (2) is opened, the input terminal (1) of the corresponding channel is directly electrically connected to the collection unit (3) to achieve resistance collection; when the output relay (7) is closed, the output terminal (8) of the corresponding channel is directly electrically connected to the input relay (2) and no data is restored; when the output relay (7) is opened, the output terminal (8) of the corresponding channel is directly electrically connected to the resistance simulator (6) to achieve resistance restoration output (6).

2. The resistance collection and output device according to claim 1, characterized in that: The number of the input relays (2), the resistance simulators (6), and the output relays (7) is set correspondingly, and the number of the input relays (2), the resistance simulators (6), and the output relays (7) is more than two, the more than two input relays (2) are respectively connected in parallel with the acquisition unit (3), and the more than two resistance simulators (6) and the output relays (7) are connected in series in pairs and then respectively connected in parallel with the control unit (5).

3. The resistance collection and output device according to claim 1, characterized in that: The acquisition unit (3) is a voltage acquisition device and / or a resistance acquisition device.

4. The resistance collection and output device according to claim 3, characterized in that: The voltage acquisition device is an analog-to-digital converter; the resistance acquisition device is a digital rheostat or an operational amplifier / comparator.

5. The resistance collection and output device according to claim 1, characterized in that: The communication unit (4) is a wired communication device or a wireless communication device.

6. The resistance collection and output device according to claim 5, characterized in that: The wired communication device is any one of a 485 communication module, an RS232 communication module, an Ethernet communication module, and an optical fiber communication module; the wireless communication device is any one of a local area network communication module or a communication module that can be plugged into an operator's SIM card.

7. The resistance collection and output device according to any one of claims 1 to 6, characterized in that: The resistance simulator (6) is a series-parallel combination of one or more digital resistors.

8. A resistance acquisition and output method, characterized in that: The resistance acquisition and output device according to any one of claims 1 to 7 is used, wherein each channel in the resistance acquisition and output device has a bypass mode, an acquisition mode, and a special mode when in operation; The bypass mode: when a channel operates in the bypass mode, the input relay (2) and the output relay (7) of the channel are both in a closed state, and the resistor connected to the resistance acquisition and output device is directly connected to the original acquisition system without being collected and restored by the resistance acquisition and output device; The acquisition mode: when a channel operates in the acquisition mode, the input relay (2) and the output relay (7) of the channel are both in an open state, the resistor connected to the resistance acquisition and output device is connected to the acquisition unit (3) through the input relay (2), the acquisition unit (3) and the control unit (5) acquire and calculate the resistance value, and after the resistance value is obtained, the control unit (5) controls the resistance simulator (6) to restore the resistance and outputs it to the original system through the output relay (7), and sends the resistance value to the remote end (9) through the communication unit (4); The special mode: when a special situation occurs in a channel operating in the acquisition mode, the control unit (5) controls the resistance simulator (6) to restore a normal resistance and outputs it to the original system through the output relay (7); and on the other hand, sends the abnormal resistance value and alarm information to the remote end (9) through the communication unit (4).

9. The resistance acquisition and output method according to claim 8, characterized in that: The actions of the resistance acquisition and output device in three modes are set by a control unit (5). When a special situation occurs in a certain channel, the acquired resistance value is sent to a remote end (9). After calculation by the remote end (9), a resistance value is returned. The control unit (5) then controls the resistance simulator (6) based on the resistance value to restore an equal resistance and output it to the original system.

10. A central air conditioning system, characterized in that: A resistance acquisition and output device according to any one of claims 1 to 7 is used, comprising a refrigeration host (21), a control cabinet (22), a terminal fan (23), a chilled water pipe (24), an outlet water temperature probe (26) and a return water temperature probe (25), wherein the outlet water temperature probe (26) and the return water temperature probe (25) are respectively connected to the control cabinet (22), the outlet water temperature probe (26) and the return water temperature probe (25) are respectively electrically connected to an input terminal of the resistance acquisition and output device, and two contacts of the control cabinet (22) are respectively connected to an output terminal of the resistance acquisition and output device; The data transmission line of the return water temperature probe (25) is as follows: the return water temperature probe (25) is electrically connected to the input terminal I, the input terminal I is correspondingly provided to the input relay I, the input relay I is electrically connected to the acquisition unit (3), the acquisition unit (3) is electrically connected to the control unit (5), the control unit (5) is electrically connected to the corresponding output relay I, and the output terminal I on the output relay I is electrically connected to a contact on the control cabinet (22); The data transmission line of the outlet water temperature probe (26) is as follows: the outlet water temperature probe (26) is electrically connected to the input terminal II, the input terminal II is correspondingly provided on the input relay II, the input relay II is electrically connected to the acquisition unit (3), the acquisition unit (3) is electrically connected to the control unit (5), the control unit (5) is electrically connected to the corresponding output relay II, and the output terminal II on the output relay II is electrically connected to another contact of the control cabinet (22); The remote end (9) sends a signal to the communication unit (4), and the communication unit (4) transmits the signal to the control unit (5). The control unit (5) controls the switches of the input relay I, the input relay II, the output relay I, and the output relay II according to the signal.

Images