Fault simulation device for temperature and pressure sensor of ammonia cracker

Abstract

The invention discloses a fault simulation device for temperature and pressure sensors of an ammonia cracker, and belongs to the technical field of sensor fault simulation. The device comprises a temperature sensor fault simulation module, a pressure sensor fault simulation module, a control module and a display module. And the temperature and pressure sensor fault simulation module is used for simulating various fault states of the temperature and pressure sensor of the ammonia cracker. The control module is used for controlling work of the temperature and pressure sensor fault simulation module and transmitting simulated fault state information to the display module to be displayed. According to the invention, various fault states of the temperature and pressure sensor of the ammonia cracker can be accurately simulated, an effective technical means is provided for fault diagnosis and maintenance of the ammonia cracker, and the reliability and safety of the system are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of sensor fault simulation, and particularly to a fault simulation device for temperature and pressure sensors of an ammonia cracker. Background Art

[0002] An ammonia cracker is a device that decomposes ammonia into hydrogen and nitrogen, and is widely used in industries such as chemical engineering, metallurgy, and electronics. The normal operation of an ammonia cracker requires temperature and pressure sensors to monitor its working state. Once the temperature and pressure sensors fail, it will affect the normal operation of the ammonia cracker and even lead to safety accidents. Therefore, it is very necessary to diagnose and maintain the temperature and pressure sensors of the ammonia cracker.

[0003] Currently, the fault diagnosis of temperature and pressure sensors of ammonia crackers mainly uses the method of off-line detection, that is, first disassemble the sensor from the ammonia cracker, and then use special detection equipment to detect the sensor. This method is not only time-consuming and laborious, but also cannot monitor the working state of the sensor in real time, and cannot meet the needs of on-line fault diagnosis and maintenance of ammonia crackers.

[0004] To solve the above problems, a device that can simulate the fault states of temperature and pressure sensors of an ammonia cracker is needed to provide an effective test means for the fault diagnosis and maintenance of the ammonia cracker. Summary of the Invention

[0005] The purpose of the present invention is to provide a fault simulation device for temperature and pressure sensors of an ammonia cracker, which can simulate the output signals of temperature and pressure sensors of an ammonia cracker in different fault states, and provides an effective test means for the fault diagnosis and maintenance of the ammonia cracker.

[0006] To achieve the above purpose, the present invention adopts the following technical solutions:

[0007] A fault simulation device for temperature and pressure sensors of an ammonia cracker, comprising a temperature sensor fault simulation module, a pressure sensor fault simulation module, a control module, and a display module;

[0008] The temperature sensor fault simulation module is used to simulate various fault states of the temperature sensor of the ammonia cracker and output corresponding simulation signals to the control module;

[0009] The pressure sensor fault simulation module is used to simulate various fault states of the pressure sensor of the ammonia cracker and output corresponding simulation signals to the control module;

[0010] The control module is used to control the operation of the temperature sensor fault simulation module and the pressure sensor fault simulation module, receive the analog signals output by the temperature sensor fault simulation module and the pressure sensor fault simulation module, and transmit the simulated fault status information to the display module for display;

[0011] The display module is used to select faults of the ammonia cracker temperature sensor and the ammonia cracker pressure sensor, and the selection result is transmitted to the control module for displaying the fault simulation results of the temperature sensor fault simulation module and the pressure sensor fault simulation module.

[0012] Compared with the prior art, the fault simulation device for the temperature and pressure sensors of an ammonia cracker according to the present invention has the following beneficial effects:

[0013] 1. It can simulate various fault states of the temperature sensor and the pressure sensor, providing an effective test means for the fault diagnosis and maintenance of the ammonia cracker.

[0014] 2. Controlled by a microprocessor, it has the advantages of high intelligence and convenient operation.

[0015] 3. It provides an innovative diagnosis technology for the ammonia cracker, facilitating users to observe and analyze.

[0016] 4. It has a simple structure, low cost, and is easy to promote and apply. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0018] FIG. 1 is a structural block diagram of the fault simulation device for the temperature and pressure sensors of the ammonia cracker according to the present invention;

[0019] FIG. 2 is a circuit schematic diagram of the fault simulation device for the temperature and pressure sensors of the ammonia cracker. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0020] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0021] To make the above objects, features, and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0022] Figure 1 is a structural block diagram of a fault simulation device for temperature and pressure sensors of an ammonia cracker according to the present invention. As Figure 1 shown, the device includes a temperature sensor fault simulation module, a pressure sensor fault simulation module, a control module, and a display module. The temperature sensor fault simulation module is used to simulate various fault states of the temperature sensor of the ammonia cracker and output corresponding simulation signals to the control module; the pressure sensor fault simulation module is used to simulate various fault states of the pressure sensor of the ammonia cracker and output corresponding simulation signals to the control module; the control module is used to control the operation of the temperature sensor fault simulation module and the pressure sensor fault simulation module, receive the simulation signals output by the temperature sensor fault simulation module and the pressure sensor fault simulation module, and transmit the simulated fault state information to the display module for display; the display module is used for fault selection of the temperature sensor of the ammonia cracker and the pressure sensor of the ammonia cracker, transmit the selection result to the control module, and for displaying the fault simulation results of the temperature sensor fault simulation module and the pressure sensor fault simulation module.

[0023] I. Temperature Sensor Fault Simulation Module

[0024] In one embodiment, the temperature sensor fault simulation module includes a resistance adjustment unit, and the resistance adjustment unit is used to adjust the resistance value of the temperature sensor fault simulation module to simulate different temperature fault states.

[0025] Next, refer to Figure 2Describe an exemplary circuit schematic diagram of a temperature sensor fault simulation module. In this example, the control module can use STM32, and its 8 pins are VCC, GPIO1, GPIO2, GPIO3, GPIO4, GPIO5, GPIO6, and GND respectively. The temperature sensor fault simulation module can use a digital potentiometer X9C103, and its 8 pins are INC, U / D, VL, GND, VCC, CS, VH, and VW respectively. The two resistors are a pull-down resistor R1 connected to the 3rd pin VL and a pull-up resistor R2 connected to the 6th pin VH. The switch is connected to the 5th pin VW. The three pins of the temperature sensor are 1st VCC, 2nd Vout, and 3rd GND respectively; the 1st pin VCC of the control module, the 8th pin VCC of the digital potentiometer X9C103, one end of the pull-up resistor R2, and the 1st pin VCC of the temperature sensor are all connected to 5V. The 2nd pin GPIO1 of the control module is connected to the 1st pin INC of the digital potentiometer X9C103 to increase the value of the digital potentiometer. The 3rd pin GPIO2 of the control module is connected to the 2nd pin U / D of the digital potentiometer X9C103 to set the adjustment direction (increase or decrease) of the digital potentiometer. The 4th pin GPIO3 of the control module is connected to the 7th pin CS of the digital potentiometer X9C103 to enable or disable the operation of the digital potentiometer. The 5th pin GPIO4 of the control module is connected to the control terminal of the switch. The 6th pin GPIO5 of the control module is connected to the 2nd pin Vout of the temperature sensor. One branch is connected to the switch. The 8th pin GND of the control module, the 4th pin GND of the digital potentiometer X9C103, one end of the pull-down resistor R1, and the 3rd pin GND of the temperature sensor are all grounded. The 3rd pin VL of the digital potentiometer X9C103 is connected to the other end of the pull-down resistor to simulate a low-end voltage of 0.1V. The 5th pin VW of the digital potentiometer X9C103 is connected to the switch to output a variable voltage from 0.1V to 4.9V. The 6th pin VH of the digital potentiometer X9C103 is connected to the other end of the pull-up resistor R2 to simulate a high-end voltage of 4.9V. The 2nd pin Vout of the temperature sensor is connected to the switch. The digital potentiometer X9C103 forms a parallel connection with the temperature sensor through the switch.

[0026] Control of the switch:

[0027] The control module controls the switch by changing the level of the GPIO4 pin according to preset conditions or external instructions. For example, when the control module STM32 detects a specific input signal or the internal logic condition is satisfied, it sends a signal to the control terminal of the switch to close or open the switch. In Figure 2In the circuit shown, the switching switch can be a relay, whose normally open contacts are connected to the GPIO pin. When the control module STM32 controls the relay coil to be energized, the contacts close, and the pins VW and the output of the temperature sensor are in parallel; when the relay coil is de-energized, the contacts open, simulating an open circuit state. The control terminal of the relay coil is connected to the GPIO4 pin of the control module STM32.

[0028] Connect the temperature sensor of the ammonia cracker to the interface of the temperature sensor fault simulation module. Set the simulated temperature fault state on the touch display screen of the display module through the control module, such as the temperature being higher than the expected value, the temperature being lower than the expected value, the temperature sensor being short-circuited or open-circuited. The control module sends corresponding control signals to the switching switch and the digital potentiometer control circuit of the temperature sensor fault simulation module according to the set fault state. The switching switch selects the connection mode of the digital potentiometer and the temperature sensor according to the signal, and the digital potentiometer adjusts the resistance value according to the control signal to simulate different temperature fault states. The simulated temperature fault state information is collected by the control module and transmitted to the display module for display.

[0029] Specific meanings of various fault states and fault state simulation:

[0030] Temperature higher than the expected value: Simulate that the temperature sensor detects that the temperature of the ammonia cracker is higher than the set working range. Among them, the control module STM32 sets U / D to low level through pin GPIO2, sets INC to low level through pin GPIO1, increases the resistance value of the digital potentiometer, makes VW less than VL, so as to reduce the total resistance of the parallel branch.

[0031] Temperature lower than the expected value: Simulate that the temperature sensor detects that the temperature of the ammonia cracker is lower than the set working range. Among them, the control module STM32 sets U / D to high level through pin GPIO2, sets INC to low level through pin GPIO1, decreases the resistance value of the digital potentiometer, makes VW greater than VH, so as to increase the total resistance of the parallel branch.

[0032] Temperature sensor short circuit: Simulate the situation where the internal circuit of the temperature sensor has a short circuit fault, resulting in the resistance approaching zero. Among them, the control module STM32 sets the resistance value of the digital potentiometer to be close to zero, sets U / D to high level through pin GPIO2, sets INC to low level through pin GPIO1 multiple times, and then closes the switching switch through pin GPIO4, so that VW is in parallel with the Vout output of the 2nd pin of the temperature sensor.

[0033] Temperature sensor open circuit: Simulate the situation where the temperature sensor is disconnected from the circuit and cannot work properly. Among them, the control module STM32 disconnects the switching switch through pin GPIO4, so that VW is disconnected from the output of the temperature sensor.

[0034] II. Pressure Sensor Fault Simulation Module

[0035] The pressure sensor fault simulation module includes a resistance adjustment unit, which is used to adjust the resistance value of the pressure sensor fault simulation module to simulate different pressure fault states.

[0036] The following refers to Figure 2 Describe an exemplary circuit schematic diagram of the pressure sensor fault simulation module. The control module can use STM32, and its 8 pins are VCC, GPIO1, GPIO2, GPIO3, GPIO4, GPIO5, GPIO6, and GND respectively. The pressure sensor fault simulation module can use the digital potentiometer X9C103, and its 8 pins are INC, U / D, VL, GND, VCC, CS, VH, and VW respectively. The two resistors are the pull-down resistor R1 connected to pin 3 and the pull-up resistor R2 connected to pin 6 respectively. There is a toggle switch. The three pins of the pressure sensor are 4 VCC, 5 Vout, and 6 GND respectively; the VCC of pin 1 of the control module, the VCC of pin 8 of the digital potentiometer X9C103, one end of the pull-up resistor R2, and the VCC of pin 4 of the pressure sensor are all connected to 5V. The GPIO1 of pin 2 of the control module is connected to the INC pin 1 of the digital potentiometer X9C103 to increment the value of the digital potentiometer. The GPIO2 of pin 3 of the control module is connected to the U / D pin 2 of the digital potentiometer X9C103 to set the adjustment direction (increment or decrement) of the digital potentiometer. The GPIO3 of pin 4 of the control module is connected to the CS pin 7 of the digital potentiometer X9C103 to enable or disable the operation of the digital potentiometer. The GPIO4 of pin 5 of the control module is connected to the control end of the toggle switch. The GPIO5 of pin 6 of the control module is connected to the Vout pin 5 of the pressure sensor. One branch is connected to the toggle switch. The GND of pin 8 of the control module, the GND of pin 4 of the digital potentiometer X9C103, one end of the pull-down resistor R1, and the GND of pin 6 of the pressure sensor are all grounded. The VL pin 3 of the digital potentiometer X9C103 is connected to the other end of the pull-down resistor to simulate the low-end voltage of 0.1V. The VW pin 5 of the digital potentiometer X9C103 is connected to the toggle switch to output a variable voltage from 0.1V to 4.9V. The VH pin 6 of the digital potentiometer X9C103 is connected to the other end of the pull-up resistor R2 to simulate the high-end voltage of 4.9V. The Vout pin 5 of the pressure sensor is connected to the toggle switch. The digital potentiometer X9C103 forms a parallel connection with the pressure sensor through the toggle switch.

[0037] Control of the toggle switch:

[0038] The control module controls the toggle switch by changing the level of the GPIO4 pin according to the preset conditions or external instructions.

[0039] For example, when the control module STM32 detects a specific input signal or internal logic conditions are met, it sends a signal to the control terminal of the switching switch to close or open the switch. In the above circuit, the switching switch can be a relay, whose normally open contacts are connected to the GPIO pin. When the control module STM32 controls the relay coil to be energized, the contacts close, and the outputs of VW and the pressure sensor are in parallel; when the relay coil is de-energized, the contacts open, simulating an open circuit state. The control terminal of the relay coil is connected to the GPIO4 pin of the control module STM32.

[0040] Connect the pressure sensor of the ammonia cracker to the interface of the pressure sensor fault simulation module. Set the simulated pressure fault state on the touch display screen of the display module through the control module, such as the pressure being higher than the expected value, the pressure being lower than the expected value, the pressure sensor being short-circuited or open-circuited. The control module sends corresponding control signals to the switching switch and the digital potentiometer control circuit of the pressure sensor fault simulation module according to the set fault state. The switching switch selects the connection mode of the digital potentiometer and the pressure sensor according to the signal, and the digital potentiometer adjusts the resistance value according to the control signal to simulate different pressure fault states. The simulated pressure fault state information is collected by the control module and transmitted to the display module for display.

[0041] Specific meanings of various fault states and fault state simulation:

[0042] Pressure higher than the expected value: Simulate that the pressure sensor detects that the pressure of the ammonia cracker is higher than the set working range. Among them, the control module STM32 sets U / D to high level through pin GPIO2, sets INC to low level through pin GPIO1, decreases the resistance value of the digital potentiometer, makes VW greater than VH, thereby increasing the total resistance of the parallel branch.

[0043] Pressure lower than the expected value: Simulate that the pressure sensor detects that the pressure of the ammonia cracker is lower than the set working range. Among them, the control module STM32 sets U / D to low level through pin GPIO2, sets INC to low level through pin GPIO1, increases the resistance value of the digital potentiometer, makes VW less than VL, thereby reducing the total resistance of the parallel branch.

[0044] Pressure sensor short circuit: Simulate the situation where the internal circuit of the pressure sensor has a short circuit fault, resulting in the resistance approaching zero. Among them, the control module STM32 sets the resistance value of the digital potentiometer to be close to zero, sets U / D to high level through pin GPIO2, sets INC to low level multiple times through pin GPIO1, and then closes the switching switch through pin GPIO4 to make VW in parallel with the Vout output of the 5th pin of the pressure sensor.

[0045] Open circuit of pressure sensor: This refers to the situation where the analog pressure sensor is disconnected from the circuit and cannot work properly. Among them, the control module STM32 disconnects the switching switch through pin GPIO4, so that VW is disconnected from the output of the pressure sensor.

[0046] III. Control Module

[0047] In one embodiment, the control module uses a microprocessor. The microprocessor communicates with the temperature sensor fault simulation module, the pressure sensor fault simulation module, and the display module through a communication interface. The communication interface is connected to the control module in a serial communication manner.

[0048] After receiving the fault simulation instruction input by the user on the touch display screen of the display module, the control module generates corresponding control signals according to the instruction and sends them to the temperature sensor fault simulation module and the pressure sensor fault simulation module through the communication interface. At the same time, the control module monitors the working status of each module in real time, collects the simulated fault status information, encodes it and then transmits it to the display module. The control module adjusts the control signal according to the feedback information to ensure the accuracy and stability of the fault simulation.

[0049] IV. Display Module

[0050] In one embodiment, the display module uses a touch display screen, which is used to display the simulated fault status information and the fault selection of the ammonia cracker temperature sensor and pressure sensor.

[0051] The display module receives the fault status information data from the control module and displays the image through the touch display screen. The display content includes the current simulated temperature fault status and pressure fault status, as well as the corresponding parameter values. Users can intuitively understand the simulated fault situation through the display module for fault diagnosis and maintenance.

[0052] As described above, only the preferred examples of the present invention are given, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution and inventive concept of the present invention, makes equivalent substitutions or changes, and should be covered by the protection scope of the present invention.

Claims

1. A fault simulation device for ammonia cracker temperature and pressure sensors, characterized in that: It includes a temperature sensor fault simulation module, a pressure sensor fault simulation module, a control module and a display module; The temperature sensor fault simulation module is used to simulate various fault states of the ammonia cracker temperature sensor and output corresponding simulation signals to the control module; The pressure sensor fault simulation module is used to simulate various fault states of the ammonia cracker pressure sensor and output corresponding simulation signals to the control module; The control module is used to control the operation of the temperature sensor fault simulation module and the pressure sensor fault simulation module, receive the simulation signals output by the temperature sensor fault simulation module and the pressure sensor fault simulation module, and transmit the simulated fault status information to the display module for display; The display module is used for fault selection of the ammonia cracker temperature sensor and the ammonia cracker pressure sensor. The selection result is transmitted to the control module for displaying the fault simulation results of the temperature sensor fault simulation module and the pressure sensor fault simulation module.

2. The fault simulation device for the temperature and pressure sensor of the ammonia cracker according to claim 1, characterized in that: The temperature sensor fault simulation module includes a resistance adjustment unit, and the resistance adjustment unit is used to adjust the resistance value of the temperature sensor fault simulation module to simulate different temperature fault states.

3. The fault simulation device for the temperature and pressure sensor of the ammonia cracker according to claim 2, characterized in that: The control module uses STM32, and its 8 pins are VCC, GPIO1, GPIO2, GPIO3, GPIO4, GPIO5, GPIO6, and GND. The temperature sensor fault simulation module uses a digital potentiometer X9C103, and its 8 pins are INC, U / D, VL, GND, VCC, CS, VH, and VW. The two resistors are the pull-down resistor R1 connected to pin 3 VL, the pull-up resistor R2 connected to pin 6 VH, and the switch connected to pin 5 VW. Switch the switch, the three pins of the temperature sensor are No. 1 VCC, No. 2 Vout, and No. 3 GND; the No. 1 pin VCC of the control module, the No. 8 pin VCC of the digital potentiometer X9C103, one end of the pull-up resistor R2 and the No. 1 pin VCC of the temperature sensor are connected to 5V, the No. 2 pin GPIO1 of the control module is connected to the No. 1 pin INC of the digital potentiometer X9C103 for increasing the value of the digital potentiometer, and the No. 3 pin GPIO2 of the control module is connected to the No. 2 pin U / D of the digital potentiometer X9C103 for setting The adjustment direction of the digital potentiometer is set (incremental or decremental). The control module No. 4 pin GPIO3 is connected to the digital potentiometer X9C103 No. 7 pin CS to enable or disable the operation of the digital potentiometer. The control module No. 5 pin GPIO4 is connected to the control end of the switch. The control module No. 6 pin GPIO5 is connected to the temperature sensor No. 2 pin Vout. One branch is connected to the switch. The control module No. 8 pin GND, the digital potentiometer X9C103 No. 4 pin GND, one end of the pull-down resistor R1 and the temperature sensor Pin 3 GND of the digital potentiometer is grounded together, Pin 3 VL of the digital potentiometer X9C103 is connected to the other end of the pull-down resistor to simulate the low-end voltage 0.1V, Pin 5 VW of the digital potentiometer X9C103 is connected to the switching switch to output a variable voltage from 0.1V to 4.9V, Pin 6 VH of the digital potentiometer X9C103 is connected to the other end of the pull-up resistor R2 to simulate the high-end voltage 4.9V, Pin 2 Vout of the temperature sensor is connected to the switching switch, and the digital potentiometer X9C103 is connected in parallel with the temperature sensor through the switching switch.

4. The fault simulation device for the temperature and pressure sensor of the ammonia cracker according to claim 3, characterized in that: The switching switch is a relay whose normally open contact is connected to the GPIO pin. When the control module STM32 controls the relay coil to be energized, the contacts are closed, and the pin VW is connected in parallel with the temperature sensor output; when the relay coil loses power, the contacts are disconnected to simulate the open circuit state, and the control end of the relay coil is connected to the GPIO4 pin of the control module STM32.

5. The fault simulation device for the temperature and pressure sensor of the ammonia cracker according to claim 4, characterized in that: When the analog temperature sensor detects that the temperature of the ammonia cracker is higher than the set working range, the control module STM32 sets U / D to a low level through the pin GPIO2 and sets INC to a low level through the pin GPIO1, and increases the resistance of the digital potentiometer to make VW less than VL, thereby reducing the total resistance of the parallel branch; When the analog temperature sensor detects that the temperature of the ammonia cracker is lower than the set working range, the control module STM32 sets U / D to a high level through the pin GPIO2 and sets INC to a low level through the pin GPIO1, and decreases the resistance value of the digital potentiometer to make VW greater than VH, thereby increasing the total resistance of the parallel branch; When a short circuit occurs in the internal circuit of the analog temperature sensor, the control module STM32 sets the resistance of the digital potentiometer to near zero, sets U / D to a high level through pin GPIO2, sets INC to a low level multiple times through pin GPIO1, and then closes the switch through pin GPIO4 to connect VW in parallel with the output Vout of pin 2 of the temperature sensor; When the analog temperature sensor is disconnected from the circuit, the control module STM32 disconnects the switch through the pin GPIO4 to disconnect VW from the output of the temperature sensor.

6. The fault simulation device for the temperature and pressure sensor of the ammonia cracker according to claim 1, characterized in that: The pressure sensor fault simulation module includes a resistance adjustment unit, and the resistance adjustment unit is used to adjust the resistance value of the pressure sensor fault simulation module to simulate different pressure fault states.

7. The fault simulation device for the temperature and pressure sensor of the ammonia cracker according to claim 6, characterized in that: When the analog pressure sensor detects that the pressure of the ammonia cracker is higher than the set working range, the control module STM32 sets U / D to a high level through the pin GPIO2 and sets INC to a low level through the pin GPIO1, and decreases the resistance of the digital potentiometer to make VW greater than VH, thereby increasing the total resistance of the parallel branch; When the analog pressure sensor detects that the pressure of the ammonia cracker is lower than the set working range, the control module STM32 sets U / D to a low level through the pin GPIO2 and sets INC to a low level through the pin GPIO1, and increases the resistance of the digital potentiometer to make VW less than VL, thereby reducing the total resistance of the parallel branch; When a short circuit occurs in the internal circuit of the analog pressure sensor, the control module STM32 sets the resistance of the digital potentiometer to near zero, sets U / D to a high level through pin GPIO2, sets INC to a low level multiple times through pin GPIO1, and then closes the switch through pin GPIO4 to connect VW in parallel with the output Vout of pin 5 of the pressure sensor; When the analog pressure sensor is disconnected from the circuit, the control module STM32 disconnects the switch through the pin GPIO4 to disconnect VW from the output of the pressure sensor.

8. The fault simulation device for the temperature and pressure sensor of the ammonia cracker according to claim 7, characterized in that: The switching switch is a relay whose normally open contacts are connected to the GPIO pin. When the control module STM32 controls the relay coil to be energized, the contacts are closed, and the VW and pressure sensor outputs are connected in parallel; when the relay coil loses power, the contacts are disconnected to simulate the open circuit state, and the control end of the relay coil is connected to the GPIO4 pin of the control module STM32.

9. The fault simulation device for temperature and pressure sensors of an ammonia cracker according to claim 1, characterized in that: The control module adopts a microprocessor, and the microprocessor communicates with the temperature sensor fault simulation module, the pressure sensor fault simulation module and the display module through a communication interface, and the communication interface is connected to the control module of the ammonia cracker in a serial communication mode.

10. The fault simulation device for temperature and pressure sensors of an ammonia cracker according to claim 1, characterized in that: The display module adopts a touch display screen, which is used to display simulated fault state information and fault selection of the ammonia cracker temperature sensor and pressure sensor.

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