Float type water level tracking control function board

Abstract

The invention discloses a float-type water level tracking control function board, and relates to the technical field of ship lift water level following positioning, and the float-type water level tracking control function board comprises a power supply unit, a DC / DC unit, a weighing input unit, a communication unit and an MCU unit, the sending permission end is controlled through a reverse circuit of a second triode and controls a fourth pin of a fourth single-chip microcomputer in the communication unit to send signals through the reverse circuit of the second triode, and when a program starts, a control pin is configured to be in an output mode and set to be in a low level, so that the situation that the function board sends data mistakenly after being started is avoided, and the service life of the function board is prolonged. When system initialization is completed and data are ready to be sent, a control pin is set to be at a high level, a second triode is conducted, and a signal is allowed to be transmitted to a fourth pin of a fourth single-chip microcomputer from a collector electrode, so that the signal is sent, a function board can be correctly initialized, sending of wrong data cannot be caused, and the system is ensured to be normal.

Description

Technical Field

[0001] The invention relates to the technical field of water level following positioning of a ship lift, and in particular to a float type water level tracking control function board. Background Art

[0002] With the development of the shipping industry, ship lifts are widely used to raise and lower ships between waterways. Accurate water level control is essential to ensure ship safety and improve traffic efficiency. A float-type water level tracking control function board is suitable for the water level following positioning system of the ship lift. The function board monitors the water level changes in real time through the float and automatically adjusts the operation of the pump to achieve precise control of the water level to prevent overflow or drying up. At the same time, it improves the automation level of the system, reduces manual intervention, and reduces operating costs. In the context of resource management and environmental protection, the application of this technology helps to achieve intelligent water management and promote sustainable development.

[0003] The existing float-type water level tracking and control function board has difficulty in maintaining stable power supply voltage and clock signal when it is turned on, resulting in the inability to initialize the function board correctly, which in turn causes the sending of erroneous data and causes system abnormalities. When the function board collects the force of the float through the weighing sensor, a ground loop is easily generated due to different ground potentials, resulting in signal distortion or equipment failure, thereby affecting the water level tracking accuracy and speed. Therefore, it is necessary to provide a float-type water level tracking and control function board to solve the above-mentioned problems. Summary of the invention

[0004] In order to solve the above technical problems, a float type water level tracking control function board is provided. The technical solution solves the problem that the existing float type water level tracking control function board proposed in the above background technology is difficult to maintain stability when it is turned on, resulting in the inability to initialize the function board correctly, which in turn causes the sending of erroneous data, resulting in system abnormalities. When the function board collects the force of the float through the weighing sensor, a ground loop is easily generated due to different ground potentials, resulting in signal distortion or equipment failure, thereby affecting the water level tracking accuracy and speed.

[0005] In order to achieve the above purpose, the technical solution adopted by the present invention is:

[0006] A float type water level tracking control function board, comprising:

[0007] A power supply unit, which provides power to the function board, and the voltage output by the power supply unit is converted by a DC / DC unit;

[0008] A DC / DC unit, wherein the DC / DC unit provides the converted voltage to the MCU unit, the communication unit, the weighing input unit and the motor drive unit respectively;

[0009] A weighing input unit, the weighing input unit comprising a weighing sensor interface, the weighing sensor interface is connected to a weighing sensor, the weighing sensor outputs a voltage follower circuit, and is received by the weighing input unit and then sent to the MCU unit;

[0010] A communication unit, wherein the communication unit comprises an RS422 interface, wherein the RS422 interface receives an RS422 signal output by the local control unit and sends the RS422 signal to the MCU unit;

[0011] An MCU unit, wherein the MCU unit sends a command signal after receiving the RS422 signal, and the command signal is received and executed by the motor drive unit;

[0012] Wherein, the MCU unit includes a main control single-chip computer, the 29th pin, the 30th pin, the 31st pin and the 32nd pin of the main control single-chip computer are electrically connected to the second pin, the first pin, the fifth pin and the sixth pin of the third single-chip computer respectively, the 81st pin, the 82nd pin, the 83rd pin and the 84th pin of the main control single-chip computer are connected in series with the seventh resistor, the 11th resistor, the tenth resistor and the eighth resistor, the seventh resistor, the 11th resistor, the tenth resistor and the eighth resistor are electrically connected to the anodes of the third light-emitting diode, the fifth light-emitting diode, the first light-emitting diode and the second light-emitting diode respectively, the cathodes of the third light-emitting diode, the fifth light-emitting diode, the first light-emitting diode and the second light-emitting diode are all grounded, and the 77th pin, the 78th pin, the 79th pin and the 80th pin of the main control single-chip computer are electrically connected to the fourth pin, the first pin, the sixth pin and the third pin of the first dip switch respectively;

[0013] The communication unit includes a fourth single-chip microcomputer, the twelfth pin and the eleventh pin of the fourth single-chip microcomputer receive the A and B signals of the RS422 signal respectively through the tenth diode and the eleventh diode, the fourth single-chip microcomputer converts the received A and B signals of the RS422 signal into TTL-level RX signals, and connects the TTL-level RX signal to the main control single-chip microcomputer through the fifth pin and the sixty-second pin of the main control single-chip microcomputer, the sixty-first pin of the main control single-chip microcomputer is electrically connected to the second pin of the fourth single-chip microcomputer, and converts the RS422 signal into Y and Z output signals, and the Y and Z output signals are sent to the local control unit after being absorbed by the twelfth diode and the thirteenth diode, the fourth pin of the fourth single-chip microcomputer is electrically connected to the collector of the second transistor, the base of the second transistor is connected in series with a thirteenth resistor, and the end of the thirteenth resistor away from the second transistor is electrically connected to the fifty-first pin of the main control single-chip microcomputer.

[0014] In an optional embodiment, the DC24V connected to the DC / DC unit is converted into DC5V, DC12V, DC15V, and DC-15V voltage outputs through a first diode, a first multi-way selection switch, a second multi-way selection switch, a third multi-way selection switch, and multiple capacitors for use by the MCU unit, the communication unit, the weighing input unit, and the motor drive unit.

[0015] In an optional embodiment, the main control microcontroller is connected to a first dip switch through a resistor-capacitor network consisting of a fourth resistor, a fifth resistor, a sixth capacitor and a seventh compensation capacitor, and the main control microcontroller is connected to a first dip switch through pin seventy-seven, pin seventy-eight, pin seventy-ninth and pin eightieth, and the first dip switch has 16 states, corresponding to 0-15 respectively, to collect address information and realize the setting of the function board address.

[0016] In an optional embodiment, the eighty-first pin, eighty-second pin, eighty-third pin and eighty-fourth pin of the main control microcontroller are respectively limited by the seventh resistor, the eleventh resistor, the tenth resistor and the eighth resistor, and drive the third light-emitting diode, the fifth light-emitting diode, the first light-emitting diode and the second light-emitting diode to complete the instructions of stop, rise, fall and communication.

[0017] In an optional embodiment, the main control microcontroller in the MCU unit interacts with the third microcontroller through pin 29, pin 30, pin 31 and pin 32 to read and write the external EEROM to complete the access operation of the control parameters.

[0018] In an optional embodiment, the twenty-sixth pin and the twenty-seventh pin of the main control microcontroller in the MCU unit are electrically connected to a third capacitor and a fourth capacitor, respectively, and one end of the third capacitor and the fourth capacitor is connected to a passive crystal oscillator, and the other end of the third capacitor and the fourth capacitor is grounded, and the passive crystal oscillator serves as a clock source for the MCU unit.

[0019] In an optional embodiment, the fourth pin of the fourth single-chip microcomputer in the communication unit is a transmission enable terminal, and the transmission enable terminal is controlled by a reverse circuit of the second transistor to avoid the function board from sending data by mistake when it is turned on.

[0020] In an optional embodiment, the second pin of the fifth single-chip microcomputer is connected to a DC15V voltage, and a DC10V voltage is output through the sixth pin. The DC10V voltage output by the sixth pin is connected to the excitation pin of the weighing sensor after being filtered by the seventh compensation capacitor and the third fuse.

[0021] In an optional embodiment, the S+ signal of the weighing sensor is connected to the IN+ of the differential amplifier after passing through a low-pass filter circuit composed of a first fuse, a first compensation resistor and a first compensation capacitor. The S- signal of the weighing sensor is connected to the IN- of the differential amplifier after passing through a low-pass filter composed of a second compensation resistor and a second compensation capacitor. The signal amplified by the differential amplifier is connected to a follower to complete impedance matching. The follower inputs the impedance-matched signal to the input end of the MCU unit through the eighteenth pin of the main control microcontroller.

[0022] In an optional embodiment, the motor drive unit receives the BREAK and PWM signals output by the MCU unit, connects to a high-speed optocoupler for electrical isolation, and then connects the signal to the motor drive chip. The DIR signal is isolated by a low-speed optocoupler and connected to the motor drive chip. The motor drive unit controls the forward and reverse rotation, stop and speed control of the motor through DIR, BREAK and PWM.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] The float type water level tracking control function board proposed in this scheme controls the fourth pin of the fourth single chip microcomputer in the communication unit to send a signal through the reverse circuit of the second transistor. At the beginning of the program, the control pin is configured as the output mode and set to a low level to avoid the function board from sending data by mistake when it is turned on. When the system is initialized and ready to send data, the control pin is set to a high level, the second transistor is turned on, and the signal is allowed to be transmitted from the collector to the fourth pin of the fourth single chip microcomputer, thereby sending a signal, so that the function board can be initialized correctly, and will not cause the sending of erroneous data, ensuring the normal operation of the system;

[0025] This scheme proposes a float type water level tracking control function board, which receives the BREAK and PWM signals output by the MCU unit through the motor drive unit, connects to the high-speed optocoupler for electrical isolation, and then connects the signal to the motor drive chip. The DIR signal is isolated by the low-speed optocoupler and connected to the motor drive chip, so as to control the forward and reverse rotation, stop and speed of the motor through DIR, BREAK and PWM, so as to avoid the signal distortion caused by the ground loop generated by different ground potentials when the function board collects the force of the float through the weighing sensor, thereby affecting the water level tracking accuracy and speed, and realizing local and remote control through RS422 communication, which is convenient for system debugging. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 A framework diagram of a float type water level tracking control function board proposed by the present invention;

[0027] Figure 2 is a circuit diagram of a DC / DC unit in the present invention;

[0028] Figure 3 and Figure 4 Combined into a circuit diagram of the MCU unit in the present invention;

[0029] Figure 5 is a circuit diagram of the communication unit in the present invention;

[0030] Figure 6 is a circuit diagram of a weighing input unit in the present invention;

[0031] Figure 7 is a circuit diagram of the motor drive unit in the present invention. DETAILED DESCRIPTION

[0032] The following description is used to disclose the present invention so that those skilled in the art can implement the present invention. The preferred embodiments described below are only examples, and those skilled in the art may think of other obvious variations.

[0033] Reference Figure 1 - Figure 7 As shown, a float type water level tracking control function board includes:

[0034] The power supply unit provides power to the function board, and the voltage output by the power supply unit is converted by the DC / DC unit;

[0035] A DC / DC unit, the DC / DC unit provides the converted voltage to the MCU unit, the communication unit, the weighing input unit and the motor drive unit respectively;

[0036] The weighing input unit includes a weighing sensor interface, the weighing sensor interface is connected to the weighing sensor, the weighing sensor outputs a voltage follower circuit, and is received by the weighing input unit and then sent to the MCU unit;

[0037] The communication unit includes an RS422 interface, which receives the RS422 signal output by the local control unit and sends the RS422 signal to the MCU unit;

[0038] MCU unit, the MCU unit sends out a command signal after receiving the RS422 signal, and the command signal is received and executed by the motor drive unit;

[0039] The MCU unit includes a main control microcontroller U2B, and the twenty-ninth pin P1.7, the thirtieth pin P1.6, the thirty-first pin P1.5 and the thirty-second pin P1.4 of the main control microcontroller U2B are electrically connected to the second pin SO, the first pin CS, the fifth pin SI and the sixth pin SCK of the third microcontroller U3B respectively, and the eighty-first pin P5.7, the eighty-second pin P5.6, the eighty-third pin P5.5 and the eighty-fourth pin P5.4 of the main control microcontroller U2B are connected in series with the seventh resistor R7B, the eleventh resistor R11B, the tenth resistor R10B and the eighth resistor R8B, and the seventh resistor R7B, the eleventh resistor R11B, the tenth resistor R10B and the eighth resistor R8B. 1B, the tenth resistor R10B and the eighth resistor R8B are electrically connected to the anode 1 of the third light-emitting diode D3B, the fifth light-emitting diode D5B, the first light-emitting diode D1B and the second light-emitting diode D2B respectively, the cathode 2 of the third light-emitting diode D3B, the fifth light-emitting diode D5B, the first light-emitting diode D1B and the second light-emitting diode D2B are all grounded DGND, and the seventy-seventh pin P6.3, the seventy-eighth pin P6.2, the seventy-ninth pin P6.1 and the eightieth pin P6.0 of the main control microcontroller U2B are electrically connected to the fourth pin 4, the first pin 1, the sixth pin 6 and the third pin 3 of the first dip switch BK1 respectively;

[0040] The communication unit includes a fourth single-chip microcomputer U4B. The twelfth pin A and the eleventh pin B of the fourth single-chip microcomputer U4B receive the A and B signals of the RS422 signal respectively through the tenth diode XD11 and the eleventh diode XD10. The fourth single-chip microcomputer U4B converts the A and B signals of the received RS422 signal into a TTL level RX signal, and connects the TTL level RX signal to the main control single-chip microcomputer U2B through the fifth pin DI and the sixty-second pin P0.0 of the main control single-chip microcomputer U2B. The sixty-first pin P0.1 of the main control single-chip microcomputer U2B is connected to The second pin RO of the fourth single-chip microcomputer U4B is electrically connected to convert the RS422 signal into Y and Z output signals. The Y and Z output signals are absorbed by the twelfth diode XD12 and the thirteenth diode XD13 and then sent to the local control unit. The fourth pin DE of the fourth single-chip microcomputer U4B is electrically connected to the collector 1 of the second transistor Q2B, and the base 2 of the second transistor Q2B is connected in series with the thirteenth resistor R13B. The end of the thirteenth resistor R13B away from the second transistor Q2B is electrically connected to the fifty-first pin P3.3 of the main control single-chip microcomputer U2B.

[0041] Furthermore, the DC24V connected to the DC / DC unit is converted into DC5V, DC12V, DC15V, and DC-15V voltage outputs respectively through the first diode D1, the first multi-way selection switch S1, the second multi-way selection switch S2, the third multi-way selection switch S3 and multiple capacitors (the first capacitor C1 to the 11th capacitor C12, and the 30th capacitor C30, the 31st capacitor C31, the 32nd capacitor C32 and the 33rd capacitor C33) for use by the MCU unit, the communication unit, the weighing input unit and the motor drive unit.

[0042] Furthermore, the main control microcontroller U2B is connected to the first dip switch BK1 through the seventy-seventh pin P6.3, the seventy-eighth pin P6.2, the seventy-ninth pin P6.1 and the eightieth pin P6.0 through the resistor-capacitor network composed of the fourth resistor R4B, the fifth resistor R5B, the sixth capacitor C6B and the seventh compensation capacitor C7B. The first dip switch BK1 has 16 states, corresponding to 0-15 respectively, to collect address information and realize the setting of the function board address.

[0043] Furthermore, the eighty-first pin P5.7, the eighty-second pin P5.6, the eighty-third pin P5.5 and the eighty-fourth pin P5.4 of the main control microcontroller U2B respectively pass through the seventh resistor R7B, the eleventh resistor R11B, the tenth resistor R10B and the eighth resistor R8B, and drive the third light-emitting diode D3B, the fifth light-emitting diode D5B, the first light-emitting diode D1B and the second light-emitting diode D2B to complete the instructions of stop, rise, fall and communication.

[0044] Furthermore, the main control microcontroller U2B in the MCU unit interacts with the third microcontroller U3B through the twenty-ninth pin P1.7, the thirtieth pin P1.6, the thirty-first pin P1.5 and the thirty-second pin P1.4 to read and write the external EEROM, thereby completing the access operation of the control parameters.

[0045] Furthermore, the twenty-sixth pin XTAL1 and the twenty-seventh pin XTAL2 of the main control microcontroller U2B in the MCU unit are electrically connected to the third capacitor C3B and the fourth capacitor C4B, respectively, and one end of the third capacitor C3B and the fourth capacitor C4B are connected to the passive crystal oscillator Y1, and the other end of the third capacitor C3B and the fourth capacitor C4B is grounded DGND, and the passive crystal oscillator Y1 serves as the clock source of the MCU unit.

[0046] Furthermore, the fourth pin DE of the fourth single-chip microcomputer U4B in the communication unit is a transmission enable terminal, and the transmission enable terminal DE is controlled by the reverse circuit of the second transistor Q2B to avoid the function board from sending data by mistake when it is turned on.

[0047] Furthermore, the second pin VDD of the fifth single-chip computer U5A is connected to a DC15V voltage, and a DC10V voltage is output through the sixth pin V-OUT. The DC10V voltage output by the sixth pin V-OUT is filtered by the seventh compensation capacitor C7A and the third fuse F3A and then connected to the excitation pin of the weighing sensor.

[0048] Furthermore, the S+ signal of the weighing sensor is connected to IN+ of the differential amplifier U1A after passing through a low-pass filter circuit composed of a first fuse F1A, a first compensation resistor R1A and a first compensation capacitor C1A. The S- signal of the weighing sensor is connected to IN- of the differential amplifier U1A after passing through a low-pass filter composed of a second compensation resistor R2A and a second compensation capacitor C2A. The signal amplified by the differential amplifier U1A is connected to the follower U2AA to complete impedance matching. The follower U2AA inputs the impedance-matched signal to the input end of the MCU unit through the eighteenth pin of the main control microcontroller U2B.

[0049] Further, see Figure 1 and Figure 7 As shown, the motor drive unit receives the BREAK and PWM signals output by the MCU unit, and is connected to the high-speed optocoupler U1C for electrical isolation, and then the signal is connected to the motor drive chip U2C. The DIR signal is isolated by the low-speed optocoupler and connected to the motor drive chip U2C. The motor drive unit controls the forward and reverse rotation, stop and speed control of the motor through DIR, BREAK and PWM. The motor drive unit receives the BREAK signal output by the eighty-sixth pin P5.2 of the main control microcontroller U2B in the MCU unit, and the PWM signal output by the main control microcontroller U2B. The PWM signal is connected to the second pin 1- of the high-speed optocoupler U1C, and the BREAK signal is connected to the third pin 2- of the high-speed optocoupler U1C, and is connected to the seventh pin OUT1 and the sixth pin OU The T6 output signal is connected to the fifth pin PWM and the fourth pin BREAK of the motor driver chip U2C. The DIR signal sent by the main control microcontroller U2B passes through the low-speed optocoupler G optocoupler (521-4) through four pins (P4.2, P4.3, P4.4 and P5.1) and is connected to the third pin DIR of the motor driver chip U2C. The DC12V output by the DC / DC unit is connected to the third pin VCC of the fourth conversion microcontroller U4C and converted to DC5V1 (VCC1). DC5V1 (VCC1) provides power for the high-speed optocoupler U1C and the low-speed optocoupler G optocoupler (521-4). The motor driver chip U2C is connected to an external DC motor through the second pin OUTPUT1 and the tenth pin OUTPUT2 to control the direction and speed of the motor.

[0050] Specifically, refer to Figure 2As shown in the figure, the DC / DC unit uses a three-phase power module (S1, S2, S3) to convert the DC24V input into DC5V, DC12V, DC-15V, and DC15V outputs. The DC24V1 input first passes through the D1 unidirectional diode to achieve reverse protection. DC24V2 passes through the filter capacitor and is connected to the input end of the three-phase power module. After each output passes through the filter capacitor, it outputs DC5V, DC12V, DC-15V, and DC15V for use by other units.

[0051] Reference Figure 3 and Figure 4 As shown, the core of the MCU unit uses a 100-pin C8051F020 chip, which realizes power-on reset through a resistor-capacitor network composed of a fourth resistor R4B, a fifth resistor R5B, a sixth capacitor C6B, and a seventh compensation capacitor C7B. The third single-chip microcomputer U3B (25045) communicates with the main single-chip microcomputer U2B through the fifth pin SI, the second pin SO, the first pin CS, and the sixth pin SCK to complete the storage and reading of data and realize the power-off protection function of the control parameters. The four pins of the main single-chip microcomputer U2B (the eighty-first pin P5.7, the eighty-second pin P5.6, the eighty-third pin P5.5, and the eighty-fourth pin P5.4) are respectively limited by the seventh resistor R7B, the eleventh resistor R11B, the tenth resistor R10B, and the eighth resistor R8B to drive four light-emitting diodes (the third light-emitting diode D3B, the fifth light-emitting diode D5B, the first light-emitting diode D1B, and the second light-emitting diode D2B) to complete the instructions of stop, rise, fall, and communication. The main control microcontroller U2B collects address information through the 77th pin P6.3, the 78th pin P6.2, the 79th pin P6.1 and the 80th pin P6.0 external dip switches to achieve the setting of the function board address.

[0052] Reference Figure 5 As shown, the communication unit uses MAX489 as the fourth single-chip microcomputer U4B (communication interface chip), and the sending enable control signal is connected to the fourth pin DE of the fourth single-chip microcomputer U4B through the thirteenth resistor R13B, the second reverse capacitor Q2B, and the twelfth resistor R12B reverse circuit to realize the sending enable control.

[0053] The working principle of the present invention is as follows: the water level tracking mark mirror realizes up and down changes synchronously with the water level through a float, a DC motor, a steering wheel, a weighing sensor, etc. The float-type water level tracking control function board receives information from the weighing sensor and the local control unit, controls the forward and reverse rotation and speed of the DC motor, and completes the control of the float and the water level tracking mark mirror.

[0054] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions only describe the principles of the present invention. The present invention may be subject to various changes and improvements without departing from the spirit and scope of the present invention. These changes and improvements fall within the scope of the present invention. The scope of protection claimed by the present invention is defined by the attached claims and their equivalents.

Claims

1. A float type water level tracking control function board, characterized in that: include: A power supply unit, which provides power to the function board, and the voltage output by the power supply unit is converted by a DC / DC unit; A DC / DC unit, wherein the DC / DC unit provides the converted voltage to the MCU unit, the communication unit, the weighing input unit and the motor drive unit respectively; A weighing input unit, the weighing input unit comprising a weighing sensor interface, the weighing sensor interface is connected to a weighing sensor, the weighing sensor outputs a voltage follower circuit, and is received by the weighing input unit and then sent to the MCU unit; A communication unit, wherein the communication unit comprises an RS422 interface, wherein the RS422 interface receives an RS422 signal output by the local control unit and sends the RS422 signal to the MCU unit; An MCU unit, wherein the MCU unit sends a command signal after receiving the RS422 signal, and the command signal is received and executed by the motor drive unit; Wherein, the MCU unit includes a main control single-chip computer, the 29th pin, the 30th pin, the 31st pin and the 32nd pin of the main control single-chip computer are electrically connected to the second pin, the first pin, the fifth pin and the sixth pin of the third single-chip computer respectively, the 81st pin, the 82nd pin, the 83rd pin and the 84th pin of the main control single-chip computer are connected in series with the seventh resistor, the 11th resistor, the tenth resistor and the eighth resistor, the seventh resistor, the 11th resistor, the tenth resistor and the eighth resistor are electrically connected to the anodes of the third light-emitting diode, the fifth light-emitting diode, the first light-emitting diode and the second light-emitting diode respectively, the cathodes of the third light-emitting diode, the fifth light-emitting diode, the first light-emitting diode and the second light-emitting diode are all grounded, and the 77th pin, the 78th pin, the 79th pin and the 80th pin of the main control single-chip computer are electrically connected to the fourth pin, the first pin, the sixth pin and the third pin of the first dip switch respectively; The communication unit includes a fourth single-chip microcomputer, the twelfth pin and the eleventh pin of the fourth single-chip microcomputer receive the A and B signals of the RS422 signal respectively through the tenth diode and the eleventh diode, the fourth single-chip microcomputer converts the received A and B signals of the RS422 signal into TTL-level RX signals, and connects the TTL-level RX signal to the main control single-chip microcomputer through the fifth pin and the sixty-second pin of the main control single-chip microcomputer, the sixty-first pin of the main control single-chip microcomputer is electrically connected to the second pin of the fourth single-chip microcomputer, and converts the RS422 signal into Y and Z output signals, and the Y and Z output signals are sent to the local control unit after being absorbed by the twelfth diode and the thirteenth diode, the fourth pin of the fourth single-chip microcomputer is electrically connected to the collector of the second transistor, the base of the second transistor is connected in series with a thirteenth resistor, and the end of the thirteenth resistor away from the second transistor is electrically connected to the fifty-first pin of the main control single-chip microcomputer.

2. A float type water level tracking control function board according to claim 1, characterized in that: The DC24V connected to the DC / DC unit is converted into DC5V, DC12V, DC15V, and DC-15V voltage outputs through the first diode, the first multi-way selection switch, the second multi-way selection switch, the third multi-way selection switch and multiple capacitors for use by the MCU unit, the communication unit, the weighing input unit and the motor drive unit.

3. A float type water level tracking control function board according to claim 1, characterized in that: The main control microcontroller is connected to a resistor-capacitor network composed of a fourth resistor, a fifth resistor, a sixth capacitor and a seventh compensation capacitor. The main control microcontroller is externally connected to a first dip switch through pin 77, pin 78, pin 79 and pin 80. The first dip switch has 16 states, corresponding to 0-15 respectively, to collect address information and realize the setting of the function board address.

4. A float type water level tracking control function board according to claim 1, characterized in that: The 81st pin, 82nd pin, 83rd pin and 84th pin of the main control microcontroller are respectively limited by the seventh resistor, the eleventh resistor, the tenth resistor and the eighth resistor, and drive the third light-emitting diode, the fifth light-emitting diode, the first light-emitting diode and the second light-emitting diode to complete the instructions of stop, rise, fall and communication.

5. A float type water level tracking control function board according to claim 1, characterized in that: The main control microcontroller in the MCU unit exchanges signals with the third microcontroller through the twenty-ninth pin, the thirtieth pin, the thirty-first pin and the thirty-second pin, reads and writes the external EEROM, and completes the access operation of the control parameters.

6. A float type water level tracking control function board according to claim 1, characterized in that: The twenty-sixth pin and the twenty-seventh pin of the main control microcontroller in the MCU unit are electrically connected to the third capacitor and the fourth capacitor respectively, and one end of the third capacitor and the fourth capacitor is connected to the passive crystal oscillator, and the other end of the third capacitor and the fourth capacitor is grounded, and the passive crystal oscillator serves as the clock source of the MCU unit.

7. A float type water level tracking control function board according to claim 1, characterized in that: The fourth pin of the fourth single-chip microcomputer in the communication unit is a transmission enable terminal, and the transmission enable terminal is controlled by the reverse circuit of the second transistor to avoid the function board from sending data by mistake when starting up.

8. A float type water level tracking control function board according to claim 1, characterized in that: The second pin of the fifth single-chip microcomputer is connected to a DC15V voltage, and a DC10V voltage is output through the sixth pin. The DC10V voltage output by the sixth pin is connected to the excitation pin of the weighing sensor after being filtered by the seventh compensation capacitor and the third fuse.

9. A float type water level tracking control function board according to claim 8, characterized in that: The S+ signal of the weighing sensor is connected to the IN+ of the differential amplifier after passing through a low-pass filter circuit composed of a first fuse, a first compensation resistor and a first compensation capacitor. The S- signal of the weighing sensor is connected to the IN- of the differential amplifier after passing through a low-pass filter composed of a second compensation resistor and a second compensation capacitor. The signal amplified by the differential amplifier is connected to the follower to complete impedance matching. The follower inputs the impedance-matched signal to the input end of the MCU unit through the eighteenth pin of the main control microcontroller.

10. A float type water level tracking control function board according to claim 1, characterized in that: The motor drive unit receives the BREAK and PWM signals output by the MCU unit, and is connected to a high-speed optocoupler for electrical isolation. The signal is then connected to the motor drive chip. The DIR signal is isolated by a low-speed optocoupler and connected to the motor drive chip. The motor drive unit controls the forward and reverse rotation, stop and speed control of the motor through DIR, BREAK and PWM.

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