Water sump high-low water level alarm device and method

Abstract

The invention discloses a water sump high-low water level alarm device and method, and relates to the technical field of water level detection, a touch screen is fixed on an explosion-proof box, a power supply module and a PLC module are both arranged in the explosion-proof box, the power supply module supplies power to the whole water level alarm device, a liquid level sensor converts collected water level data into electric signals and sends the electric signals to the PLC module, and the PLC module sends the electric signals to the touch screen; the touch screen receives and displays the water level information output by the PLC module, the touch screen is used for inputting an alarm threshold value of the explosion-proof voice box, and the PLC module compares the received water level value with the set alarm threshold value and drives the explosion-proof voice box to give out a voice alarm when the received water level value exceeds the alarm threshold value. The water level can be detected, the high-water-level alarm threshold value and the low-water-level alarm threshold value can be set on the touch screen according to the actual situation, and guarantee is provided for safe operation of the water pump house. According to the invention, data collected underground on site can be sent to a ground dispatching room through the shielding signal line, and the water levels of a plurality of water sumps can be monitored at the same time.

Description

Technical Field

[0001] The present invention relates to the technical field of water level detection, and in particular to a high and low water level alarm device and method for a sump. Background Art

[0002] The "Coal Mine Safety Production Standardization" requires that the water pump room must be equipped with water level observation and high and low water level sound and light alarm devices. At present, the water level measurement of the water tank in the mine is usually carried out by a water level sensor, which has a single function and can only display the water level without high and low water level alarm functions. The workers on duty cannot grasp the water level in the water tank in time and cannot pump water in time to start and stop the water pump. Failure to stop the pump in time will increase the wear of the multi-stage pump, and even dry grinding and ablation will increase the amount of manual maintenance. Failure to start the pump in time will bring hidden dangers to the safe operation of the water pump room.

[0003] Combined with Figure 1-2 At present, the commonly used mining immersion level sensor model is GUY10 (A), which is based on a single-chip microcomputer. The signal output by the probe is amplified and converted into a digital signal after A / D conversion, enters the single-chip microcomputer, and after processing, it is digitally displayed through a digital tube, and the frequency signal is output through the signal output circuit. It cannot save alarm information, has a single function, and is expensive. It cannot be used for water level experiments on site. The output signal is a frequency of 200-1000Hz, which is not convenient for association with other equipment. The operation is more complicated when setting the alarm value. The cost of a single unit is about 3,000 yuan. One device can only monitor one water tank. When monitoring multiple water tanks, wiring is increased, which increases equipment investment.

[0004] Therefore, a high and low water level alarm device and method for a sump have become problems that need to be solved urgently. Summary of the invention

[0005] The purpose of the present invention is to provide a water tank high and low water level alarm device and method to solve the problems of high cost of existing equipment, need for conversion of uploaded data, complex setting operation, high equipment cost, and inconvenience in on-site alarm experiments.

[0006] To achieve the above-mentioned purpose, the technical solution provided by the present invention is: a high and low water level alarm device for a water tank, comprising an explosion-proof box, a power module, a touch screen, a liquid level sensor, a PLC module and an explosion-proof voice box;

[0007] The touch screen is fixed on the explosion-proof box, the power module and the PLC module are both arranged in the explosion-proof box, the power module supplies power to the entire water level alarm device, the liquid level sensor is electrically connected to the PLC module and converts the collected water level data into electrical signals and sends them to the PLC module, the touch screen is electrically connected to the PLC module and the explosion-proof voice box, the touch screen receives and displays the water level information output by the PLC module, the touch screen is used to input the alarm threshold of the explosion-proof voice box, the PLC module compares the received water level value with the set alarm threshold, and drives the explosion-proof voice box to emit sound and light signal alarms when the alarm threshold is exceeded.

[0008] Furthermore, it also includes an analog quantity acquisition module, which connects the PLC module and the liquid level sensor and converts the electrical signal output by the liquid level sensor into a digital signal for the PLC module to read and calculate.

[0009] Furthermore, a power switch for controlling the power module is provided in the explosion-proof box.

[0010] Furthermore, an explosion-proof bell mouth is provided on a side wall of the explosion-proof box, and the explosion-proof bell mouth is connected to the electronic device in the box and the liquid level sensor outside the box through a shielded signal line.

[0011] Furthermore, an intrinsically safe junction box is provided on the shielded signal line.

[0012] Furthermore, the explosion-proof box includes a box body and a box door, and the box body and the box door are rotatably connected via a hinge.

[0013] Furthermore, the box door is provided with explosion-proof glass, and the touch screen is embedded in the explosion-proof glass.

[0014] Furthermore, screw holes are provided at corresponding positions of the box door and the edge of the box body.

[0015] Furthermore, the liquid level sensors are provided in a plurality and are respectively located in different water tanks.

[0016] The present invention also provides a water tank high and low water level alarm method, comprising the following steps:

[0017] Set the alarm threshold of each water tank through the touch screen, including the upper limit threshold H of the high water level max and the lower water level threshold H min ;

[0018] The liquid level sensors are located in different water tanks, and the water level data of each water tank is collected in real time. The collected liquid level data is processed by the sliding average filter method. Let the liquid level value currently collected by the i-th sensor be h i (n), the filter window size is m, then the liquid level value after filtering is The calculation formula is:

[0019]

[0020] Where n is the current number of acquisitions; in this way, some short-term fluctuations can be smoothed out to obtain a more stable liquid level value.

[0021] The analog quantity acquisition module receives the electrical signal output by the liquid level sensor and converts it into a digital signal.

[0022] The PLC module reads the converted digital signal, i.e. the water level value of each water tank; the PLC module compares the received water level value with the alarm threshold set on the touch screen. If the water level value exceeds the preset high water level threshold or is lower than the preset low water level threshold, the PLC module determines that the water level is abnormal.

[0023] When the PLC module determines that the water level is abnormal, it first drives the explosion-proof voice box to send out sound and light signal alarms, reminding the operator to pay attention to the abnormal water level in an intuitive way.

[0024] The touch screen displays the current water level information and alarm status of each water tank in real time, which is convenient for operators to view and record.

[0025] Abnormal liquid level judgment:

[0026] Set the upper and lower limit thresholds H of the liquid level max and H min For each tank’s level sensor data Determine whether it is satisfied if or The water tank liquid level is determined to be abnormal, an alarm signal is triggered, and the abnormal time and abnormal liquid level value are recorded.

[0027] Silo level calculation:

[0028] For non-abnormal liquid level data, calculate the total water tank liquid level H total . Assume that there are N water tanks, and the effective bottom area of ​​each water tank is S i (pre-measured and stored in the system), the total water tank level calculation formula is:

[0029]

[0030] This formula calculates the overall liquid level based on the weighted average of the liquid level and bottom area of ​​each water tank, and can reflect the comprehensive liquid level status of the entire water tank system.

[0031] Data storage and transmission:

[0032] The processed liquid level data (including the filtered liquid level value of each water tank, whether it is abnormal, the total water tank liquid level, etc.) is stored in the database in a certain format for subsequent query and analysis. At the same time, the data can be transmitted to the monitoring center or other related systems through the network as needed to achieve remote monitoring.

[0033] Through the above data collection and processing methods, the data of multiple liquid level sensors can be effectively utilized to accurately monitor the liquid level conditions of different water tanks, and obtain comprehensive liquid level information, so as to detect abnormalities in time and take corresponding measures.

[0034] The advantages of the present invention compared with the prior art are:

[0035] (1) The present invention can not only detect the water level, but also set the thresholds of high water level and low water level alarms on the touch screen according to actual conditions, thereby providing a guarantee for the safe operation of the pump room and reducing equipment loss.

[0036] (2) The present invention can clearly display the actual value of the water level in the water tank in real time with high accuracy.

[0037] (3) The present invention can send the data collected underground to the ground dispatching room through the shielded signal line, and can monitor the water level of the water tank at the same time.

[0038] (5) One device can be used for multiple purposes. Multiple water tanks can be monitored at the same time, saving equipment investment.

[0039] (6) The device of the present invention has a reasonable and simple structure, is easy to install and use, has strong practicality, and is easy to promote. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 This is a structural diagram of the existing liquid level sensor GUY10(A).

[0041] Figure 2 This is the electrical schematic diagram of the liquid level sensor GUY10(A).

[0042] Figure 3 The invention discloses a structural schematic diagram of a water tank high and low water level alarm device and method.

[0043] Figure 4 It is a system diagram of a water tank high and low water level alarm device and method of the present invention.

[0044] Figure 5 The invention discloses a circuit schematic diagram of a high and low water level alarm device for a water tank.

[0045] As shown in the figure: 1. Explosion-proof box, 2. Power module, 3. Touch screen, 4. Liquid level sensor, 5. PLC module, 6. Explosion-proof voice box, 7. Analog acquisition module, 9. Power switch, 10. Explosion-proof horn, 11. Shielded signal line, 12. Intrinsically safe junction box, 13. Box body, 14. Box door, 15. Hinge, 16. Explosion-proof glass, 17. Screw hole. DETAILED DESCRIPTION

[0046] In the description of the present invention, it is necessary to understand that the orientations or positional relationships indicated by terms such as “upper”, “lower”, “front”, “back”, “left”, “right”, “inside”, “outside”, “vertical” and “circumferential” are based on the orientations or positional relationships shown in the accompanying drawings and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0047] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0048] The following is a further detailed description of a silo high and low water level alarm device and method of the present invention in conjunction with the accompanying drawings.

[0049] Combined with Figure 3-5 , the present invention is introduced in detail.

[0050] A high and low water level alarm device and method for a water tank, comprising an explosion-proof box 1, a power module 2, a touch screen 3, a liquid level sensor 4, a PLC module 5 and an explosion-proof voice box 6. The touch screen 3 is fixed on the explosion-proof box 1, and the power module 2 and the PLC module 5 are both arranged in the explosion-proof box 1. The power module 2 is of model MDR-60-24; the power module 2 provides a 24V DC voltage to the touch screen 3, the liquid level sensor 4 and the PLC module 5. The liquid level sensor 4 is electrically connected to the PLC module 5, and is used to measure the water level of the water tank and convert it into a 4-20mA current signal and send it to the PLC module 5. The touch screen 3 is connected to the PLC module 5 and the explosion-proof voice box 6 through a shielded twisted pair (two-wire system), and data is exchanged using an RS485 serial communication method. The touch screen 3 receives the water level information output by the PLC module 5 and displays it intuitively, and at the same time, the alarm threshold of the PLC internal register can be changed on the touch screen 3 according to actual conditions. The PLC module 5 compares the received water level value with the set alarm threshold, and drives the explosion-proof voice box 6 to emit an audible and visual alarm signal when the alarm threshold is exceeded, and sends the water level data to the touch screen 3 to display the real-time water level. The PLC module 5 can be selected as model 224XP CN DC / DC / RLY.

[0051] Furthermore, the present invention also includes an analog quantity acquisition module 7, which is a matching analog quantity acquisition module 7 provided with the PLC module 5 and converts the 4-20mA current signal output by the liquid level sensor 4 into a digital signal for the PLC module 5 to read and calculate.

[0052] A power switch 9 for controlling the power module 2 is provided in the explosion-proof box 1, so that the user can control the switch state of the entire device conveniently.

[0053] An explosion-proof bell mouth 10 is provided on the side wall of the explosion-proof box 1, and the bell mouth connects the electronic device in the box body 13 and the liquid level sensor 4 outside the box body 13 through the shielded signal line 11 to ensure the safety and stability of signal transmission. An intrinsically safe junction box 12 is provided on the shielded signal line 11, which is used for the transition connection between the liquid level sensor 4 and the shielded line, further improving the explosion-proof performance of the device.

[0054] The explosion-proof box 1 includes a box body 13 and a box door 14, which are rotatably connected by a hinge 15, so that the user can easily maintain and operate the device. The box door 14 is provided with an explosion-proof glass 16, and the touch screen 3 is embedded in the explosion-proof glass 16, which not only ensures that the touch screen 3 is clearly visible, but also improves the safety of the device. The box door 14 and the box body 13 are provided with screw holes 17 at the corresponding positions of the edges, which are used to fix the box door 14 to ensure the stability of the device.

[0055] The explosion-proof box 1 is rectangular and made of carbon steel. All non-intrinsically safe components are installed in the explosion-proof box 1 and comply with the provisions of the "Coal Mine Safety Regulations". The water level data displayed on the touch screen 3 is observed through the explosion-proof glass 16. It is connected to the external power cord through the explosion-proof horn 10, connected to the external explosion-proof voice box 6, and connected to the external intrinsically safe junction box 12 and the liquid level sensor 4. The explosion-proof box 1 adopts a special explosion-proof design, which can operate safely in an environment containing gas and coal dust to prevent explosions caused by failure of internal electrical components. It has waterproof and dustproof functions to adapt to the harsh environment of damp and dusty underground in coal mines.

[0056] In order to monitor multiple water tanks, the liquid level sensor 4 in the present invention is provided with several and is respectively located in different water tanks, and the water level data of each water tank is uniformly managed and processed by the PLC module 5. The liquid level sensor 4 can be selected as GH-136-10 / 10-4, and the output is 4-20 ma , detection range 0-10 meters.

[0057] The present invention also provides a water tank high and low water level alarm method, comprising the following steps:

[0058] Set alarm thresholds for each water tank through the touch screen, including the upper threshold of high water level H max and low water mark thresholds H min;

[0059] The liquid level sensors are located in different water tanks, and the water level data of each water tank is collected in real time. The collected liquid level data is processed by the sliding average filter method. Let the liquid level value currently collected by the i-th sensor be h i (n), the filter window size is m, then the liquid level value after filtering is The calculation formula is:

[0060]

[0061] Where n is the current number of acquisitions; in this way, some short-term fluctuations can be smoothed out to obtain a more stable liquid level value.

[0062] The analog quantity acquisition module receives the electrical signal output by the liquid level sensor and converts it into a digital signal.

[0063] The PLC module reads the converted digital signal, i.e. the water level value of each water tank; the PLC module compares the received water level value with the alarm threshold set on the touch screen. If the water level value exceeds the preset high water level threshold or is lower than the preset low water level threshold, the PLC module determines that the water level is abnormal.

[0064] When the PLC module determines that the water level is abnormal, it first drives the explosion-proof voice box to send out sound and light signal alarms, reminding the operator to pay attention to the abnormal water level in an intuitive way.

[0065] The touch screen displays the current water level information and alarm status of each water tank in real time, which is convenient for operators to view and record.

[0066] Abnormal liquid level judgment:

[0067] Set the upper and lower limit thresholds H of the liquid level max and H min For each tank’s level sensor data Determine whether it is satisfied if or The water tank liquid level is determined to be abnormal, an alarm signal is triggered, and the abnormal time and abnormal liquid level value are recorded.

[0068] Silo level calculation:

[0069] For non-abnormal liquid level data, calculate the total water tank liquid level Htotal. Assume that there are N water tanks, and the effective bottom area of ​​each water tank is S i (pre-measured and stored in the system), the total water tank level calculation formula is:

[0070]

[0071] This formula calculates the overall liquid level based on the weighted average of the liquid level and bottom area of ​​each water tank, and can reflect the comprehensive liquid level status of the entire water tank system.

[0072] Data storage and transmission:

[0073] The processed liquid level data (including the filtered liquid level value of each water tank, whether it is abnormal, the total water tank liquid level, etc.) is stored in the database in a certain format for subsequent query and analysis. At the same time, the data can be transmitted to the monitoring center or other related systems through the network as needed to achieve remote monitoring.

[0074] Through the above data collection and processing methods, the data of multiple liquid level sensors can be effectively utilized to accurately monitor the liquid level conditions of different water tanks, and obtain comprehensive liquid level information, so as to detect abnormalities in time and take corresponding measures.

[0075] Liquid level control strategy based on set value

[0076] Level set point determination:

[0077] According to the purpose of the water tank (such as water supply, drainage, etc.), a desired liquid level target value H is pre-set targetFor example, for the water supply tank, it is necessary to ensure that there is sufficient water supply, H target It may be set to about 70% of the tank capacity; for drain tanks, H target Might be set to a lower value to prevent water from overflowing.

[0078] The PID feedback control algorithm is used to control the output. The calculation formula of the control output u(t) is:

[0079]

[0080] where e(t) = H target -H total (t) is the liquid level deviation, K p , K i and K d They are proportional, integral and differential coefficients. By adjusting these coefficients, the control output (such as flow regulation of a pump or opening regulation of a valve) can be adjusted to reduce the level deviation.

[0081] For example, when the liquid level is lower than the target value H target When the liquid level is higher than the target value, e(t)<0, the control output will reduce the flow of water into the water tank (such as closing the water inlet valve) or increase the drainage flow (such as opening the drainage pump or drainage valve).

[0082] The specific implementation process of a water tank high and low water level alarm device and method of the present invention is as follows:

[0083] The liquid level sensor 4 is placed in the water tank to be monitored, and the water level depth is converted into a 4-20mA analog electrical signal by the sensor, and then transmitted to the multi-channel analog acquisition module 7 through the shielded signal line 11 to convert the analog electrical signal into a digital signal for identification by the PLC module 5. The programmed PLC module 5 obtains the data and processes and calculates the data, converting it into the actual water level value. The touch screen 3 reads the water level value and displays it for the staff to understand the water level of the water tank.

[0084] Click the setting button on the touch screen 3 to enter the value and set the high and low values ​​of the water level alarm value by changing the internal vw register value of the PLC module 5. When the actual water level is not within the set range, after the PLC module 5 compares and judges with the set threshold, the internal relay is activated to connect the power supply, and the explosion-proof voice box 6 issues a voice alarm to remind the staff to start or stop the pump in time. When the water level reaches the normal level, the alarm stops automatically.

[0085] The present invention can use an explosion-proof box 1 and a touch screen 3 to realize water level monitoring and alarm of multiple water tanks, and one device has multiple uses. One explosion-proof box 1 can lead to at least three liquid level sensors 4, which are placed in different water absorption wells. A small amount of external components can be freely added according to the on-site conditions to monitor multiple water tanks.

[0086] Control logic relationship description:

[0087] The liquid level sensor 4 is placed at the bottom of the water tank. The higher the water level, the greater the pressure on the liquid level sensor 5, and vice versa. According to this principle, the change of water depth is converted into an electrical signal (and the probe measurement range of 0-10 meters corresponds to a 4-20ma current signal). The current signal is transmitted to the EM235 module (an accessory of the PLC module 5 and the analog quantity acquisition module 7, which is connected to the main module PLC through a strip cable) through a two-core shielded cable through the intrinsically safe junction box 12 (which serves to connect the sensor wiring length). The analog signal is converted into a digital signal. Since the two signals are linearly related, the function relationship A=f(D) can be expressed as a mathematical equation: A=(D-D0)X(Am-A0) / (Dm-D0)+A0; the external input 4-20ma current signal corresponds to a value of 6400-32000, completing the conversion of the analog signal into a digital value and storing it in the VW register. Take one of the routes as an example, the principle process; integer to double integer - double integer to real number - floating point number division to get the actual value with decimal point, and store it in the VD register for touch screen 3 to read and display (actual value of water level). Alarm principle: Use touch screen 3 to write a warning point value (power-off save) to the VD register of PLC and compare it with the actual water level. When it is higher (or lower) than the input value, after a certain delay, the internal relay of PLC will act, triggering the voice alarm box 6 to issue a high water level or low water level alarm. (When the water level is between the high alarm value and the low alarm value, the internal relay of PLC will not act, and the voice box will not issue an alarm.) The duration of the alarm sound can be adjusted according to the actual situation on site. Multiple water tanks share one explosion-proof voice box 6, and record different voices for each route in advance, which will be triggered by the PLC relay.

[0088] The present invention and its embodiments are described above, and such description is not restrictive. The drawings show only one embodiment of the present invention, and the actual structure is not limited thereto. In short, if ordinary technicians in the field are inspired by it, without departing from the purpose of the invention, they can design a structure and embodiment similar to the technical solution without creativity, which should belong to the protection scope of the present invention.

Claims

1. A high and low water level alarm device for a water tank, characterized in that: It comprises an explosion-proof box (1), a power module (2), a touch screen (3), a liquid level sensor (4), a PLC module (5) and an explosion-proof voice box (6); The touch screen (3) is fixed on the explosion-proof box (1); the power module (2) and the PLC module (5) are both arranged in the explosion-proof box (1); the power module (2) supplies power to the entire water level alarm device; a plurality of liquid level sensors (4) are provided and are respectively arranged in different water tanks; the liquid level sensors (4) are electrically connected to the PLC module (5) and convert the collected water level data into electrical signals and send them to the PLC module (5); the touch screen (3) is electrically connected to the PLC module (5) and the explosion-proof voice box (6); the touch screen (3) receives and displays the water level information output by the PLC module (5); the touch screen (3) is used to input the alarm threshold of the explosion-proof voice box (6); the PLC module (5) compares the received water level value with the set alarm threshold, and drives the explosion-proof voice box (6) to emit an audible and visual signal alarm when the alarm threshold is exceeded.

2. A water tank high and low water level alarm device according to claim 1, characterized in that: It also comprises an analog quantity acquisition module (7), which is connected to the PLC module (5) and the liquid level sensor (4) and converts the electrical signal output by the liquid level sensor (4) into a digital signal for the PLC module (5) to perform reading operations.

3. A water tank high and low water level alarm device according to claim 2, characterized in that: A power switch (9) for controlling the power module (2) is provided in the explosion-proof box (1).

4. A water tank high and low water level alarm device according to claim 3, characterized in that: The explosion-proof box (1) is provided with an explosion-proof bell mouth (10) on the side wall, and the explosion-proof bell mouth (10) is connected to the electronic device in the box body (13) and the liquid level sensor (4) outside the box body (13) through a shielded signal line (11).

5. A water tank high and low water level alarm device according to claim 4, characterized in that: An intrinsically safe junction box (12) is provided on the shielded signal line (11).

6. A water tank high and low water level alarm device according to claim 5, characterized in that: The explosion-proof box (1) comprises a box body (13) and a box door (14), and the box body (13) and the box door (14) are rotatably connected via a hinge (15).

7. A water tank high and low water level alarm device according to claim 6, characterized in that: The box door (14) is provided with explosion-proof glass (16), and the touch screen (3) is embedded in the explosion-proof glass (16).

8. A water tank high and low water level alarm device according to claim 7, characterized in that: Screw holes (17) are provided at positions corresponding to the edges of the box door (14) and the box body (13).

9. A method for high and low water level alarm in a water tank, characterized in that: The following steps are included: Set the alarm threshold of each water tank through the touch screen, including the upper limit threshold H of the high water level max and the lower water level threshold H min ; The liquid level sensors are located in different water tanks, and the water level data of each water tank is collected in real time. The collected liquid level data is processed by the sliding average filter method. Suppose the liquid level value currently collected by the i-th sensor is h i (n), the filter window size is m, then the liquid level value after filtering is The calculation formula is: Where n is the current number of acquisitions; The analog quantity acquisition module receives the electrical signal output by the liquid level sensor and converts it into a digital signal; The PLC module reads the converted digital signal, that is, the water level value of each water tank; for each water tank liquid level sensor data The PLC module determines whether if or If the liquid level in the water tank is abnormal, an alarm signal is triggered, and the abnormal time and abnormal liquid level value are recorded; When the PLC module determines that the water tank liquid level is abnormal, it first drives the explosion-proof voice box to send out sound and light signal alarms to remind the operator to pay attention to the abnormal water level; For non-abnormal liquid level data, calculate the total water tank liquid level H total ; Assume there are N water tanks, and the effective bottom area of ​​each water tank is S i , then the total water tank level calculation formula is: The processed liquid level data, including the filtered liquid level value of each water tank, whether it is abnormal, and the total water tank liquid level, are stored in the database in a certain format for subsequent query and analysis; at the same time, they are displayed in real time on the touch screen.

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