Floating ball type liquid level meter calibration device

Abstract

The invention discloses a floating ball type liquid level meter calibration device which comprises a square box, a liquid inlet, a check valve, an electromagnetic valve, a filter, a liquid inlet pump, a liquid inlet pipeline, a liquid inlet pump connecting flange, a filter connecting flange, an electromagnetic valve connecting flange, a check valve connecting flange and a control console. The liquid inlet pipeline is sequentially connected with the check valve, the electromagnetic valve, the filter and the liquid inlet pump from left to right. The check valve is fixed to the portion, between the liquid inlet and the electromagnetic valve, of the liquid inlet pipeline through a check valve connecting flange, the electromagnetic valve is fixed to the portion, between the electromagnetic valve and the filter, of the liquid inlet pipeline through an electromagnetic valve connecting flange, and a filter connecting flange is arranged on the portion, between the filter and the liquid inlet pump, of the liquid inlet pipeline. The liquid inlet pump is fixed on the liquid inlet pipeline through the liquid inlet pump connecting flange; according to the method, the high-precision radar liquid level meter is used as a reference, the liquid level meter to be detected is calibrated, and confidence results of different liquid level ranges can be obtained.

Description

Technical Field

[0001] The invention relates to the technical field of liquid level gauge calibration, and in particular to a float type liquid level gauge calibration device. Background Art

[0002] The "Liquefied Gas Tank Truck" standard stipulates that due to the maximum filling volume requirement for liquefied gas, at least one liquid level gauge must be installed on the tank body; during use, the liquid level change of the medium in the tank truck and the shaking of the liquid medium during the vehicle's driving will cause an impact on the liquid level gauge, causing its body to deform or even damage; not only that, because impurities in the liquid medium are often adsorbed on the connecting rod or float, the float's up and down movement is restricted or even blocked. Therefore, the "Rules for Periodic Inspection of Pressure Vessels" stipulate that the inspection agency should inspect the liquid level gauge when conducting regular inspections on tank trucks. The inspection content includes whether the liquid level gauge is damaged or deformed, and whether the indication is accurate, otherwise it must be calibrated. Not only that, during the use of the tank truck liquid level gauge, the operator can judge the operating status of the tank truck and the flow of the liquid through the measurement data of the liquid level gauge, so as to adjust and optimize the production process. If the liquid level is too high, the liquid may overflow from the equipment, causing environmental pollution and safety accidents; if the liquid level is too low, the equipment may be evacuated, damaging the equipment or affecting production efficiency; by adjusting the liquid level in the tank, the loading and unloading efficiency of the tank truck can be optimized; the accurate measurement and real-time monitoring of the liquid level gauge can also promptly detect and deal with abnormal liquid levels such as leaks. Traditional calibration methods usually use macroscopic inspection methods, or use measuring tools such as steel tape measures to check the scale of the liquid level gauge. Due to the lack of dedicated inspection equipment, the inspection accuracy is low, especially the lack of targeted inspection at the extreme liquid level, and the lack of liquid level display accuracy under different working conditions such as extremely low, extremely high, and drastic liquid level fluctuations, leaving a large safety hazard for the use of tank trucks. Summary of the invention

[0003] The purpose of the present invention is to overcome the shortcomings of the above-mentioned background technology and to provide a float type liquid level gauge calibration device, which uses a high-precision radar liquid level gauge (accuracy ±1mm) as a calibrated liquid level gauge, simulates the driving process of a tank truck in a square box container, and the working state of liquid level fluctuation during liquid filling and unloading, and divides the liquid level height into eight characteristic ranges (characteristic liquid levels L1, L2, L3, L4, L5, L6, L7) according to the working conditions, focusing on the correction of the detection results of the universal float liquid level gauge (accuracy above ±10mm) at extremely low and extremely high liquid levels, and finally gives the display accuracy of the liquid level gauge to be tested in different liquid level ranges.

[0004] The technical scheme of the present invention is: a float type liquid level gauge calibration device, which comprises: a square box, a liquid inlet, a check valve, a solenoid valve, a filter, a liquid inlet pump, a liquid inlet pipeline, a liquid inlet pump connecting flange, a filter connecting flange, a solenoid valve connecting flange, a check valve connecting flange, and a control console, wherein a liquid inlet is provided at the lower right corner inside the square box, the liquid inlet is connected to the liquid inlet pipeline, and the liquid inlet pipeline is respectively connected to the check valve, the solenoid valve, the filter, and the liquid inlet pump from left to right; the check valve is fixed to the liquid inlet pipeline between the liquid inlet and the solenoid valve through the check valve connecting flange, the solenoid valve is fixed to the liquid inlet pipeline between the solenoid valve and the filter through the solenoid valve connecting flange, the liquid inlet pipeline between the filter and the liquid inlet pump is provided with a filter connecting flange, and the liquid inlet pump is fixed to the liquid inlet pipeline through the liquid inlet pump connecting flange;

[0005] The square box is composed of legs, characteristic liquid level markings, radar level gauge I, liquid level gauge to be checked, adjustment block, top plate, liquid inlet, electromagnetic relief valve, connecting rod, float, radar level gauge II. Legs for fixing and supporting the square box are respectively arranged at the positions around the bottom of the square box, and an electromagnetic relief valve is arranged at the middle position of the bottom of the square box. Characteristic liquid level markings are arranged on the inner and outer surfaces of the square box. A top plate is arranged on the top of the square box. Radar level gauge I and radar level gauge II are respectively arranged at the two ends of the top plate. A liquid level gauge to be checked and an adjustment block are arranged at the middle position of the top plate. The liquid level gauge to be checked is fixed to the adjustment block by bolts. The connecting rod is threadedly connected to the liquid level gauge to be checked. The float is sleeved on the connecting rod, and the connecting rod is connected to the electromagnetic relief valve.

[0006] The control console is respectively connected with the radar level gauge I, the radar level gauge II, the level gauge to be inspected, the electromagnetic discharge valve, the electromagnetic valve and the liquid inlet pump circuit.

[0007] The circuit of the control console in the float type liquid level gauge calibration device is set as a three-phase five-wire circuit, and the circuit includes: surge protector, liquid inlet pump current relay, communication interface RS485, liquid inlet pump circuit breaker, solenoid valve circuit breaker, solenoid valve AC contactor, control power circuit breaker, power switch, power indicator, PLC power circuit breaker, DC power circuit breaker, rectifier, console emergency stop button, system start button, system stop button, touch screen, network cable interface, communication interface, alarm indication switch, buzzer switch, liquid inlet pump operation switch, programmable logic controller (PLC), grounding, equipment casing grounding, PLC expansion module, isolator G1, liquid inlet pump operation indication, alarm indication, buzzer, electromagnetic discharge valve switch, electromagnetic discharge valve indication, electromagnetic discharge valve AC contactor, electromagnetic discharge valve circuit breaker;

[0008] A, B, C, N and PE wires are arranged in the three-phase five-wire circuit, wherein A, B and C are three wires in the three-phase electrical system, N is the ground wire, and PE is the protective ground wire; the five wires are all connected to the surge protector, the A, B and C wires are connected to the liquid inlet pump circuit breaker, and then connected to the communication interface RS485, the liquid inlet pump current relay is connected to the RS485DI1 end and the COM end of the communication interface, the U1V1W1 end is connected to the liquid inlet pump, and the 485A and 485B ends are respectively connected to the communication interface; the A and N wires are connected to the solenoid valve circuit breaker, and then connected to the solenoid valve AC contactor; the A and N wires are connected to the control power circuit breaker, and then connected to the wires L1 and L2; the A and N wires are connected to the electromagnetic discharge valve circuit breaker, and then connected to the electromagnetic discharge valve AC contactor;

[0009] The wire L1 is connected to a power switch, and then connected in parallel to a PLC power circuit breaker and a DC power circuit breaker, and power indicators are connected to the wires L1 and L2; the PLC power circuit breaker is connected to a wire L3, and connected to a programmable logic controller (PLC) power supply terminal together with the wire L2; the DC power circuit breaker is connected to a wire L7, and connected to a rectifier together with the wire L2, and then respectively connected to the positive (24V) and negative (24G) terminals of the programmable logic controller (PLC) DC power supply;

[0010] The positive terminal (24V) of the DC power supply of the programmable logic controller (PLC) is connected in parallel to the emergency stop button, the system start button, and the system stop button of the console, and then connected to the input relay terminals 0, 1, and 2 of the programmable logic controller (PLC) respectively; the network cable interface in the programmable logic controller (PLC) is connected to the network cable interface in the touch screen with a network cable; the output relay terminals 0, 1, 2, and 3 of the programmable logic controller (PLC) are respectively connected to the alarm indication switch, the buzzer switch, the liquid inlet pump operation switch, and the electromagnetic discharge valve switch; the device housing grounding in the programmable logic controller (PLC) is connected to the ground;

[0011] The PLC expansion module is connected to a dedicated interface of a programmable logic controller (PLC); the terminals 0+, 0-, 1+, 1-, 2+, and 2- in the PLC expansion module are respectively connected to the terminals 5, 6, 11, 12, 13, and 14 in the isolator G1; the terminals 1, 2, 3, 4, 7, and 8 in the isolator G1 are respectively connected to the radar level gauge I signal terminals 401+ and 401-, the radar level gauge II signal terminals 402+ and 402-, and the signal terminals 403+ and 403- of the level gauge to be inspected; the terminals 9 and 10 in the isolator G1 are respectively connected to the positive (24V) and negative (24G) terminals of the DC power supply in the programmable logic controller (PLC);

[0012] The liquid inlet pump operation switch is connected in parallel with the liquid inlet pump operation indication and the electromagnetic valve AC contactor, the alarm indication switch is connected with the alarm indication, the buzzer switch is connected with the buzzer, and the electromagnetic discharge valve switch is connected in parallel with the electromagnetic discharge valve indication and the electromagnetic discharge valve AC contactor.

[0013] The specific operation process of the float type liquid level gauge calibration device is as follows:

[0014] The first step is to install the liquid level gauge to be inspected on the adjustment block and start the liquid inlet process verification through the console;

[0015] The second step is to turn on the power switch SA1 in the console, and the power indicator H1 lights up; turn on the system start button, and the AC 220V (50HZ) connects the PLC power circuit breaker and the DC power circuit breaker. The rectifier rectifies the AC 220V (50HZ) into 24V DC, providing power for the console emergency stop button, system start button, system stop button, and the programmable logic controller PLC to output 24V DC; the programmable logic controller PLC starts and sends a signal to the communication interface RS485 through the communication interface, and the liquid pump fills the liquid according to the liquid filling mode 1 (flow rate 2m / s). , radar level gauge I, radar level gauge II and the level gauge to be tested start measuring the liquid level values, and transmit the results to the input end of isolator G1 through signal lines respectively. Isolator G1 is not only used to protect the lower control loop and weaken the influence of environmental noise on the circuit, but also to suppress the interference of common ground, solenoid valve and unknown pulse on the equipment, and convert the input signal and output it to the PLC expansion module; the programmable logic controller PLC determines whether the measurement value of radar level gauge I or radar level gauge II reaches the characteristic liquid level (L1, L2, L3, L4, L5, L6, L7) through the PLC expansion module;

[0016] If so, the console issues a command to stop the liquid inlet pump and close the solenoid valve;

[0017] If not, continue to determine whether the liquid level is the characteristic liquid level L1, L2, L3, L4, L5, L6, L7. At this time, the solenoid valve remains open, and when the liquid level is in the range of [0, L3], continue to use the liquid inlet pump to infuse liquid; when the liquid level is in the range of [L3, L4], the liquid inlet pump infuse liquid according to the liquid inlet mode 2 (flow rate 1m / s, frequency 10HZ); when the liquid level is in the range of (L4, L7], the liquid inlet pump infuse liquid according to the liquid inlet mode 3 (flow rate 0.5m / s); When the system determines that the characteristic liquid level is L1, L2, L3, L5, L6, and L7, after waiting for 10 seconds, the radar level gauge I, radar level gauge II, and the level gauge to be tested record the measured values ​​and transmit the results to the input end of the isolator G1; when the characteristic liquid level is L4, the radar level gauge I, radar level gauge II, and the level gauge to be tested record the liquid level values ​​every 3 seconds (a total of 10 seconds) and transmit the results to the input end of the isolator G1; the relevant process parameters can be queried in real time through the touch screen;

[0018] In the third step, after the measurement of the liquid inlet process is completed, the programmable logic controller PLC is used to control the electromagnetic discharge valve switch, the electromagnetic discharge valve indicator, and the electromagnetic discharge valve AC contactor to open the electromagnetic discharge valve with a liquid discharge speed of 1m / s; the radar level gauge I, the radar level gauge II, and the level gauge to be tested record the measured values; the programmable logic controller PLC determines whether the measured value of the radar level gauge I or the radar level gauge II reaches the characteristic liquid level L1, L2, L3, L4, L5, L6 through the PLC expansion module;

[0019] If yes, use the programmable logic controller PLC to control the electromagnetic relief valve switch to disconnect, close the electromagnetic relief valve, wait for 10 seconds, and then the radar level meter I, radar level meter II and the level meter to be tested will record the measured values ​​and transmit the results to the input end of the isolator G1;

[0020] If not, continue to keep the electromagnetic discharge valve open, unload the liquid at a speed of 1m / s, and continue to determine whether the liquid level is the characteristic liquid level L1, L2, L3, L4, L5, L6, L7, until the calibration of the level meter to be inspected is completed; the console outputs the calibration result, and then starts the calibration of the next level meter.

[0021] Compared with the prior art, the present invention uses a high-precision radar level gauge as a benchmark to calibrate the level gauge to be inspected, and can obtain confidence results in different liquid level ranges; according to the liquid level characteristics of the level gauge during use, focus is placed on the display of the level gauge under extreme liquid level conditions; the medium working conditions during the use of the tank truck are simulated, and the display results of the level gauge are checked under impact (liquid inlet mode one), vibration (liquid inlet mode two) and static (liquid inlet mode three) modes, which can more realistically reflect the measurement conditions of the level gauge under different working conditions; finally, the display accuracy of the level gauge to be inspected in different liquid level ranges is given. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic diagram of the structure of the present invention;

[0023] Figure 2 It is a left-side structural schematic diagram of the present invention;

[0024] Figure 3 It is a schematic diagram of the top view structure of the present invention;

[0025] Figure 4 This is the main circuit diagram of the console of the present invention;

[0026] Figure 5 This is the control loop diagram of the present invention;

[0027] Figure 6 It is the PLC module diagram of the present invention;

[0028] Figure 7 This is a diagram of the PLC expansion module of the present invention;

[0029] Figure 8 This is a connection circuit diagram of the isolator of the present invention;

[0030] Fig. 9 This is the peripheral control circuit diagram of the present invention;

[0031] Among them: 1. Leg, 2. Box, 3. Characteristic liquid level mark, 4. Radar level gauge I, 5. Level gauge to be inspected, 6. Adjustment block, 7. Top plate, 8. Liquid inlet, 9. Solenoid discharge valve, 10. Check valve, 11. Solenoid valve, 12. Filter, 13. Liquid inlet pump, 14. Liquid inlet pipeline, 15. Liquid inlet pump connecting flange, 16. Filter connecting flange, 17. Solenoid valve connecting flange, 18. Check valve connecting flange, 19. Control console, 20. Connecting rod, 21. Float, 22. Radar level gauge II, 23. Surge protector, 24. Liquid inlet pump current relay, 25. Communication interface RS485, 26. Liquid inlet pump circuit breaker, 27. Solenoid valve circuit breaker, 28. Solenoid valve AC contactor, 29. Control power circuit breaker, 30. Power switch, 31. Power indication, 32. PLC power circuit breaker, 33. DC power circuit breaker, 34. Rectifier, 35. Console emergency stop button, 36. System start button, 37. System stop button, 38. Touch screen, 39. Network cable interface, 40. Communication interface, 41. Alarm indication switch, 42. Buzzer switch, 43. Liquid inlet pump operation switch, 44. Programmable logic controller (PLC), 45. Grounding, 46. Equipment casing grounding, 47. PLC expansion module, 48. Isolator G1, 49. Liquid inlet pump operation indication, 50. Alarm indication, 51. Buzzer, 52. Electromagnetic discharge valve switch, 53. Electromagnetic discharge valve indication, 54. Electromagnetic discharge valve AC contactor, 55. Electromagnetic discharge valve circuit breaker. DETAILED DESCRIPTION

[0032] The present embodiment is a float type liquid level gauge calibration device, which comprises: a square box (2), a liquid inlet (8), a check valve (10), a solenoid valve (11), a filter (12), a liquid inlet pump (13), a liquid inlet pipeline (14), a liquid inlet pump connecting flange (15), a filter connecting flange (16), a solenoid valve connecting flange (17), a check valve connecting flange (18), and a control console (19).

[0033] like Figure 1 , Figure 2 , Figure 3 As shown, a liquid inlet (8) is provided at the lower right corner of the square box (2), and the liquid inlet (8) is connected to a liquid inlet pipe (14). The liquid inlet pipe (14) is respectively connected to a check valve (10), a solenoid valve (11), a filter (12), and a liquid inlet pump (13) from left to right; the check valve (10) is fixed to the liquid inlet pipe (14) between the liquid inlet (8) and the solenoid valve (11) through a check valve connecting flange (18); the solenoid valve (11) is fixed to the liquid inlet pipe (14) between the solenoid valve (11) and the filter (12) through a solenoid valve connecting flange (17); a filter connecting flange (16) is provided on the liquid inlet pipe (14) between the filter (12) and the liquid inlet pump (13); and the liquid inlet pump (13) is fixed to the liquid inlet pipe (14) through a liquid inlet pump connecting flange (15);

[0034] The square box (2) is composed of legs (1), characteristic liquid level markings (3), radar level gauge I (4), a liquid level gauge to be inspected (5), an adjustment block (6), a top plate (7), a liquid inlet (8), an electromagnetic discharge valve (9), a connecting rod (20), a floating ball (21), and a radar level gauge II (22). Legs (1) for fixing and supporting the square box are respectively arranged at positions around the bottom of the square box (2). An electromagnetic discharge valve (9) is arranged at a middle position of the bottom of the square box (2). Characteristic liquid level markings are arranged on both the inner and outer surfaces of the square box (2). (3), a top plate (7) is provided on the top of the square box (2), a radar level gauge I (4) and a radar level gauge II (22) are provided at both ends of the top plate (7), a level gauge to be checked (5) and an adjustment block (6) are provided at the middle of the top plate (7), the level gauge to be checked (5) is fixed to the adjustment block (6) by bolts, the connecting rod (20) is threadedly connected to the level gauge to be checked (5), the float (21) is sleeved on the connecting rod (20), and the connecting rod (20) is connected to the electromagnetic discharge valve (9);

[0035] The control console (19) is respectively connected to the radar level meter I (4), the radar level meter II (22), the level meter to be inspected (5), the electromagnetic discharge valve (9), the electromagnetic valve (11) and the liquid inlet pump (13) circuit.

[0036] like Figure 4 As shown, the circuit of the control console in the float type liquid level gauge calibration device is set as a three-phase five-wire circuit, and the circuit includes: a surge protector, a liquid inlet pump current relay, a communication interface RS485, a liquid inlet pump circuit breaker, a solenoid valve circuit breaker, a solenoid valve AC contactor, a control power circuit breaker, a power switch, a power indicator, a PLC power circuit breaker, a DC power circuit breaker, a rectifier, a console emergency stop button, a system start button, a system stop button, a touch screen, a network cable interface, a communication interface, an alarm indicator switch, a buzzer switch, a liquid inlet pump operation switch, a programmable logic controller (PLC), grounding, equipment casing grounding, a PLC expansion module, an isolator G1, a liquid inlet pump operation indication, an alarm indication, a buzzer, an electromagnetic discharge valve switch, an electromagnetic discharge valve indication, an electromagnetic discharge valve AC contactor, and an electromagnetic discharge valve circuit breaker;

[0037] A, B, C, N and PE wires are arranged in a three-phase five-wire circuit, wherein A, B and C are three wires in a three-phase electrical system, N is a ground wire, and PE is a protective ground wire; the five wires are all connected to a surge protector (23); the A, B and C wires are connected to a liquid inlet pump circuit breaker (26), and then connected to a communication interface RS485 (25); the DI1 terminal and the COM terminal of the communication interface RS485 (25) are connected to a liquid inlet pump current relay (24); the U1V1W1 terminal is connected to a liquid inlet pump (13); and the 485A and 485B terminals are respectively connected to a communication interface (40); the A and N wires are connected to a solenoid valve circuit breaker (27), and then connected to a solenoid valve AC contactor (28); the A and N wires are connected to a control power circuit breaker (29), and then connected to wires L1 and L2; the A and N wires are connected to an electromagnetic discharge valve circuit breaker (55), and then connected to an electromagnetic discharge valve AC contactor (54);

[0038] like Figure 5 As shown, the wire L1 is connected to a power switch (30), and then connected in parallel to a PLC power circuit breaker (32) and a DC power circuit breaker (33); the wires L1 and L2 are connected to a power indicator (31); the PLC power circuit breaker (32) is connected to a wire L3, and together with the wire L2, is connected to a power supply terminal of a programmable logic controller (PLC) (44); the DC power circuit breaker (33) is connected to a wire L7, and together with the wire L2, is connected to a rectifier (34), and then respectively connected to the positive (24V) and negative (24G) terminals of the DC power supply of the programmable logic controller (PLC) (44);

[0039] like Figure 6As shown, the positive terminal (24V) of the DC power supply of the programmable logic controller (PLC) (44) is connected in parallel to the emergency stop button (35), the system start button (36), and the system stop button (37) of the console, and then connected to the input relay terminals 0, 1, and 2 of the programmable logic controller (PLC) (44) respectively; the network cable interface (39) in the programmable logic controller (PLC) (44) and the network cable interface (39) in the touch screen (38) are connected by a network cable; the output relay terminals 0, 1, 2, and 3 of the programmable logic controller (PLC) (44) are respectively connected to the alarm indication switch (41), the buzzer switch (42), the liquid inlet pump operation switch (43), and the electromagnetic discharge valve switch (52); the equipment housing ground (46) in the programmable logic controller (PLC) (44) is connected to the ground (45);

[0040] like Figure 7 , Figure 8 As shown, the PLC expansion module (47) is connected to the dedicated interface of the programmable logic controller (PLC) (44); the connection terminals 0+, 0-, 1+, 1-, 2+, and 2- in the PLC expansion module (47) are respectively connected to the connection terminals 5, 6, 11, 12, 13, and 14 in the isolator G1 (48); the connection terminals 1, 2, 3, 4, 7, and 8 in the isolator G1 (48) are respectively connected to the signal terminals 401+ and 401- of the radar level gauge I (4), the signal terminals 402+ and 402- of the radar level gauge II (22), and the signal terminals 403+ and 403- of the level gauge to be inspected (5); the connection terminals 9 and 10 in the isolator G1 (48) are respectively connected to the positive (24V) and negative (24G) terminals of the DC power supply in the programmable logic controller (PLC) (44);

[0041] like Fig. 9 As shown, the liquid inlet pump operation switch (43) is connected in parallel to the liquid inlet pump operation indication (49) and the electromagnetic valve AC contactor (28), the alarm indication switch (41) is connected to the alarm indication (50), the buzzer switch (42) is connected to the buzzer (51), and the electromagnetic discharge valve switch (52) is connected in parallel to the electromagnetic discharge valve indication (53) and the electromagnetic discharge valve AC contactor (54).

[0042] The specific operation process of the float type liquid level gauge calibration device is as follows:

[0043] The first step is to install the liquid level meter (5) to be inspected on the adjustment block (7) and start the liquid inlet process verification through the control console (19);

[0044] The surge protector (23) in the three-phase five-wire circuit provides safety protection for various electronic equipment, instruments and communication lines in the control system and keeps them in working condition; the AC 380V (50HZ) provides power for the liquid inlet pump; the liquid inlet pump circuit breaker (26, 25A) is connected to the incoming line, and in addition to connecting and disconnecting the circuit, it can also protect against short circuit and overload; the liquid inlet pump current relay (24) is used to control the flow direction, size and switch of the current of the communication interface RS485 (25); the AC 220 V (50HZ) is used as the control power supply, and then connected to the control power supply circuit breaker (29, 10A) for controlling the connection and disconnection of the console power supply and protecting against short circuit and overload; the alternating current 220V (50HZ) is then connected in parallel to the electromagnetic valve circuit breaker (27, 10A) and the electromagnetic discharge valve circuit breaker (27, 10A), and then respectively connected to the electromagnetic valve AC contactor (28) and the electromagnetic discharge valve AC contactor (55), which can allow a large current to pass through and has overcurrent or grounding protection functions;

[0045] The second step is to turn on the power switch SA1 (30) in the control console (19), and the power indicator H1 (31) lights up; turn on the system start button (36), and the AC 220V (50HZ) connects the PLC power circuit breaker (32) and the DC power circuit breaker (33). The rectifier (34) rectifies the AC 220V (50HZ) into 24V DC power, providing power for the console emergency stop button (35), the system start button (36), the system stop button (37) and the programmable logic controller PLC (44) to output 24V DC power; the programmable logic controller PLC (44) starts, sends a signal to the communication interface RS485 (25) through the communication interface (40), and the liquid inlet pump (13) is operated according to the liquid inlet mode. When liquid is introduced into the device at a flow rate of 2 m / s, the radar level gauge I (4), the radar level gauge II (22) and the level gauge to be inspected (5) start to measure the liquid level value, and transmit the results to the input end of the isolator G1 (48) through the signal line respectively. The isolator G1 (48) is not only used to protect the control circuit of the lower level and weaken the influence of environmental noise on the circuit, but also to suppress the interference of the common ground, the solenoid valve and unknown pulses on the equipment, and converts the input signal and outputs it to the PLC expansion module (47); the programmable logic controller PLC (44) determines whether the measurement value of the radar level gauge I (4) or the radar level gauge II (22) reaches the characteristic liquid level (L1, L2, L3, L4, L5, L6, L7) through the PLC expansion module (47);

[0046] If yes, the control console (19) issues a command to stop the liquid inlet pump (13) and close the solenoid valve (11);

[0047] If not, it continues to determine whether the liquid level is the characteristic liquid level L1, L2, L3, L4, L5, L6, L7. At this time, the solenoid valve (11) remains open, and when the liquid level is within the range of [0, L3], the liquid inlet pump (13) continues to be used to infuse liquid; when the liquid level is within the range of [L3, L4], the liquid inlet pump (13) infuse liquid according to the second liquid inlet mode (flow rate 1m / s, frequency 10HZ); when the liquid level is within the range of (L4, L7], the liquid inlet pump infuse liquid according to the third liquid inlet mode (flow rate 0.5m / s); the system determines that the characteristic liquid level is L 1, L2, L3, L5, L6, L7, after waiting for 10 seconds, the radar level gauge I (4), radar level gauge II (22) and the level gauge to be checked (5) record the measured values ​​and transmit the results to the input end of the isolator G1 (48); when the characteristic liquid level is L4, the radar level gauge I (4), radar level gauge II (22) and the level gauge to be checked (5) record the liquid level values ​​every 3 seconds (a total of 10 seconds) and transmit the results to the input end of the isolator G1 (48); the relevant process parameters can be queried in real time through the touch screen (38);

[0048] In the third step, after the measurement of the liquid inlet process is completed, the electromagnetic discharge valve switch (52), the electromagnetic discharge valve indicator (53), and the electromagnetic discharge valve AC contactor (54) are controlled by the programmable logic controller PLC (44) to open the electromagnetic discharge valve (9) and discharge the liquid at a speed of 1 m / s; the radar level gauge I (4), the radar level gauge II (22) and the liquid level gauge to be tested (5) record the measured values; the programmable logic controller PLC (44) determines whether the measured value of the radar level gauge I (4) or the radar level gauge II (22) reaches the characteristic liquid level L1, L2, L3, L4, L5, L6 through the PLC expansion module (47);

[0049] If yes, the electromagnetic discharge valve switch (52) is turned off by the programmable logic controller PLC (44), the electromagnetic discharge valve (9) is closed, and after waiting for 10 seconds, the radar level meter I (4), the radar level meter II (22) and the level meter to be tested (5) record the measured values ​​and transmit the results to the input end of the isolator G1 (48);

[0050] If not, the electromagnetic discharge valve is kept open, the liquid discharge speed is 1m / s, and the liquid level is continuously determined to be the characteristic liquid level L1, L2, L3, L4, L5, L6, L7, until the calibration of the liquid level meter to be inspected (5) is completed; the control console (19) outputs the calibration result, and then the calibration of the next liquid level meter is started.

Claims

1. A float type liquid level gauge calibration device, characterized in that it include: Square box, liquid inlet, check valve, solenoid valve, filter, liquid inlet pump, liquid inlet pipeline, liquid inlet pump connecting flange, filter connecting flange, solenoid valve connecting flange, check valve connecting flange, control console, the liquid inlet is provided at the lower right corner inside the square box, the liquid inlet is connected to the liquid inlet pipeline, the liquid inlet pipeline is respectively connected to the check valve, solenoid valve, filter, and liquid inlet pump from left to right; the check valve is fixed to the liquid inlet pipeline between the liquid inlet and the solenoid valve through the check valve connecting flange, the solenoid valve is fixed to the liquid inlet pipeline between the solenoid valve and the filter through the solenoid valve connecting flange, the liquid inlet pipeline between the filter and the liquid inlet pump is provided with a filter connecting flange, and the liquid inlet pump is fixed to the liquid inlet pipeline through the liquid inlet pump connecting flange; The square box is composed of legs, characteristic liquid level markings, radar level gauge I, liquid level gauge to be checked, adjustment block, top plate, liquid inlet, electromagnetic relief valve, connecting rod, float, radar level gauge II. Legs for fixing and supporting the square box are respectively arranged at the positions around the bottom of the square box, and an electromagnetic relief valve is arranged at the middle position of the bottom of the square box. Characteristic liquid level markings are arranged on the inner and outer surfaces of the square box. A top plate is arranged on the top of the square box. Radar level gauge I and radar level gauge II are respectively arranged at the two ends of the top plate. A liquid level gauge to be checked and an adjustment block are arranged at the middle position of the top plate. The liquid level gauge to be checked is fixed to the adjustment block by bolts. The connecting rod is threadedly connected to the liquid level gauge to be checked. The float is sleeved on the connecting rod, and the connecting rod is connected to the electromagnetic relief valve. The control console is respectively connected with the radar level gauge I, the radar level gauge II, the level gauge to be inspected, the electromagnetic discharge valve, the electromagnetic valve and the liquid inlet pump circuit.

2. A float type liquid level gauge calibration device according to claim 1, characterized in that The circuit of the control console in the float type liquid level gauge calibration device is set as a three-phase five-wire circuit, and the circuit includes: surge protector, liquid inlet pump current relay, communication interface RS485, liquid inlet pump circuit breaker, solenoid valve circuit breaker, solenoid valve AC contactor, control power circuit breaker, power switch, power indicator, PLC power circuit breaker, DC power circuit breaker, rectifier, console emergency stop button, system start button, system stop button, touch screen, network cable interface, communication interface, alarm indication switch, buzzer switch, liquid inlet pump operation switch, programmable logic controller (PLC), grounding, equipment casing grounding, PLC expansion module, isolator G1, liquid inlet pump operation indication, alarm indication, buzzer, electromagnetic discharge valve switch, electromagnetic discharge valve indication, electromagnetic discharge valve AC contactor, electromagnetic discharge valve circuit breaker; A, B, C, N and PE wires are arranged in the three-phase five-wire circuit, wherein A, B and C are three wires in the three-phase electrical system, N is the ground wire, and PE is the protective ground wire; the five wires are all connected to the surge protector, the A, B and C wires are connected to the liquid inlet pump circuit breaker, and then connected to the communication interface RS485, the liquid inlet pump current relay is connected to the RS485DI1 end and the COM end of the communication interface, the U1V1W1 end is connected to the liquid inlet pump, and the 485A and 485B ends are respectively connected to the communication interface; the A and N wires are connected to the solenoid valve circuit breaker, and then connected to the solenoid valve AC contactor; the A and N wires are connected to the control power circuit breaker, and then connected to the wires L1 and L2; the A and N wires are connected to the electromagnetic discharge valve circuit breaker, and then connected to the electromagnetic discharge valve AC contactor; The wire L1 is connected to a power switch, and then connected in parallel to a PLC power circuit breaker and a DC power circuit breaker, and power indicators are connected to the wires L1 and L2; the PLC power circuit breaker is connected to a wire L3, and connected to a programmable logic controller (PLC) power supply terminal together with the wire L2; the DC power circuit breaker is connected to a wire L7, and connected to a rectifier together with the wire L2, and then respectively connected to the positive (24V) and negative (24G) terminals of the programmable logic controller (PLC) DC power supply; The positive terminal (24V) of the DC power supply of the programmable logic controller (PLC) is connected in parallel to the emergency stop button, the system start button, and the system stop button of the console, and then connected to the input relay terminals 0, 1, and 2 of the programmable logic controller (PLC) respectively; the network cable interface in the programmable logic controller (PLC) is connected to the network cable interface in the touch screen with a network cable; the output relay terminals 0, 1, 2, and 3 of the programmable logic controller (PLC) are respectively connected to the alarm indication switch, the buzzer switch, the liquid inlet pump operation switch, and the electromagnetic discharge valve switch; the device housing grounding in the programmable logic controller (PLC) is connected to the ground; The PLC expansion module is connected to a dedicated interface of a programmable logic controller (PLC); the terminals 0+, 0-, 1+, 1-, 2+, and 2- in the PLC expansion module are respectively connected to the terminals 5, 6, 11, 12, 13, and 14 in the isolator G1; the terminals 1, 2, 3, 4, 7, and 8 in the isolator G1 are respectively connected to the radar level gauge I signal terminals 401+ and 401-, the radar level gauge II signal terminals 402+ and 402-, and the signal terminals 403+ and 403- of the level gauge to be inspected; the terminals 9 and 10 in the isolator G1 are respectively connected to the positive (24V) and negative (24G) terminals of the DC power supply in the programmable logic controller (PLC); The liquid inlet pump operation switch is connected in parallel with the liquid inlet pump operation indication and the electromagnetic valve AC contactor, the alarm indication switch is connected with the alarm indication, the buzzer switch is connected with the buzzer, and the electromagnetic discharge valve switch is connected in parallel with the electromagnetic discharge valve indication and the electromagnetic discharge valve AC contactor.

3. A float type liquid level gauge calibration device according to claim 1, characterized in that The specific operation process of the float type liquid level gauge calibration device is as follows: The first step is to install the liquid level gauge to be inspected on the adjustment block and start the liquid inlet process verification through the console; The second step is to turn on the power switch SA1 in the console, and the power indicator H1 lights up; turn on the system start button, and the AC 220V (50HZ) connects the PLC power circuit breaker and the DC power circuit breaker. The rectifier rectifies the AC 220V (50HZ) into 24V DC, providing power for the console emergency stop button, system start button, system stop button, and the programmable logic controller PLC to output 24V DC; the programmable logic controller PLC starts and sends a signal to the communication interface RS485 through the communication interface, and the liquid pump fills the liquid according to the liquid filling mode 1 (flow rate 2m / s). , radar level gauge I, radar level gauge II and the level gauge to be tested start measuring the liquid level values, and transmit the results to the input end of isolator G1 through signal lines respectively. Isolator G1 is not only used to protect the lower control loop and weaken the influence of environmental noise on the circuit, but also to suppress the interference of common ground, solenoid valve and unknown pulse on the equipment, and convert the input signal and output it to the PLC expansion module; the programmable logic controller PLC determines whether the measurement value of radar level gauge I or radar level gauge II reaches the characteristic liquid level (L1, L2, L3, L4, L5, L6, L7) through the PLC expansion module; If so, the console issues a command to stop the liquid inlet pump and close the solenoid valve; If not, continue to determine whether the liquid level is the characteristic liquid level L1, L2, L3, L4, L5, L6, L7. At this time, the solenoid valve remains open, and when the liquid level is in the range of [0, L3], continue to use the liquid inlet pump to infuse liquid; when the liquid level is in the range of [L3, L4], the liquid inlet pump infuse liquid according to the liquid inlet mode 2 (flow rate 1m / s, frequency 10HZ); when the liquid level is in the range of (L4, L7], the liquid inlet pump infuse liquid according to the liquid inlet mode 3 (flow rate 0.5m / s); When the system determines that the characteristic liquid level is L1, L2, L3, L5, L6, and L7, after waiting for 10 seconds, the radar level gauge I, radar level gauge II, and the level gauge to be tested record the measured values ​​and transmit the results to the input end of the isolator G1; when the characteristic liquid level is L4, the radar level gauge I, radar level gauge II, and the level gauge to be tested record the liquid level values ​​every 3 seconds (a total of 10 seconds) and transmit the results to the input end of the isolator G1; the relevant process parameters can be queried in real time through the touch screen; In the third step, after the measurement of the liquid inlet process is completed, the programmable logic controller PLC is used to control the electromagnetic discharge valve switch, the electromagnetic discharge valve indicator, and the electromagnetic discharge valve AC contactor to open the electromagnetic discharge valve with a liquid discharge speed of 1m / s; the radar level gauge I, the radar level gauge II, and the level gauge to be tested record the measured values; the programmable logic controller PLC determines whether the measured value of the radar level gauge I or the radar level gauge II reaches the characteristic liquid level L1, L2, L3, L4, L5, L6 through the PLC expansion module; If yes, use the programmable logic controller PLC to control the electromagnetic relief valve switch to disconnect, close the electromagnetic relief valve, wait for 10 seconds, and then the radar level meter I, radar level meter II and the level meter to be tested will record the measured values ​​and transmit the results to the input end of the isolator G1; If not, continue to keep the electromagnetic discharge valve open, unload the liquid at a speed of 1m / s, and continue to determine whether the liquid level is the characteristic liquid level L1, L2, L3, L4, L5, L6, L7, until the calibration of the level meter to be inspected is completed; the console outputs the calibration result, and then starts the calibration of the next level meter.

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