Valve control system

Abstract

The present invention provides a valve control system, comprising: a control signal module and a valve control circuit board; the valve control circuit board comprises a parallel valve opening control module and a valve closing control module; the valve opening control module comprises a first switch unit, a first timed closing circuit and a valve opening relay, one end of the first timed closing circuit is connected to the first switch unit, and the other end of the first timed closing circuit is connected to the valve opening relay; the closing of the first switch unit is controlled by an opening command from the control signal module; the valve closing control module comprises a second switch unit, a second timed closing circuit and a valve closing relay, one end of the second timed closing circuit is connected to the second switch unit, and the other end of the second timed closing circuit is connected to the valve closing relay; the closing of the second switch unit is controlled by a closing command from the control signal module.

Description

Technical Field

[0001] The present invention relates to the field of automatic control technology, and in particular to a valve control system. Background Art

[0002] Nuclear-grade valve control boxes are electronically controlled devices used in nuclear power plants to control the electric actuators of valves such as fire dampers and smoke exhaust dampers. These control boxes control the opening and closing of the valve actuators, display their open and closed status, and feature control interfaces for remote control and monitoring of the actuators.

[0003] In the related art, the valve control box is mainly assembled from electrical equipment such as circuit breakers, time relays, and contactors. The box is relatively large in size, and the number of valve control channels generally does not exceed 4. When there are many electric valve executions on site, the arrangement of more valve control boxes will result in a large number of on-site control boxes, occupying more installation space and being inconvenient to operate. Valve control boxes are divided into different types according to their purpose and the number of valves they control. The large number of types is not convenient for the procurement, design, and manufacture of equipment. Since imported discrete electrical components are used in the manufacturing, there are many devices in the control circuit. When the equipment fails, professional and experienced engineers are required to conduct inspections. It takes a lot of time to troubleshoot the fault and complete the repair by replacing the faulty components. The fault recovery time is relatively long.

[0004] In related technologies, a programmable controller (PLC) can also be used to configure digital input and output modules to achieve miniaturization of the control box. However, the equipment needs to be programmed, and the control system containing software is not suitable for industries with high control requirements such as nuclear power.

[0005] How to provide a relatively small valve control box suitable for the nuclear power field has become an urgent problem to be solved. Summary of the Invention

[0006] The present invention provides a valve control system to solve the defects in the prior art that the valve control box needs to occupy too much installation space, the small valve control box needs to be programmed, and is not suitable for nuclear power. The valve control system can be reduced in size, is implemented purely by hardware, does not require programming, and is suitable for the nuclear power field.

[0007] The present invention provides a valve control system, comprising:

[0008] Control signal module and valve control circuit board;

[0009] The valve control circuit board includes a parallel valve opening control module and a valve closing control module;

[0010] The valve opening control module includes a first switch unit, a first timed closing circuit, and a valve opening relay. One end of the first timed closing circuit is connected to the first switch unit, and the other end of the first timed closing circuit is connected to the valve opening relay. The closing of the first switch unit is controlled by an opening command from the control signal module. The start time T1 of the first timed closing circuit is the time when the first switch unit is closed, and the disconnect time of the first timed closing circuit is T2, where T2 = T1 + t1, and t1 is the timing duration of the first timed closing circuit.

[0011] The valve closing control module includes a second switch unit, a second timed closing circuit and a valve closing relay, one end of the second timed closing circuit is connected to the second switch unit, and the other end of the second timed closing circuit is connected to the valve closing relay; the closing of the second switch unit is controlled by the closing command from the control signal module; wherein, the starting time T3 of the second timed closing circuit is the time when the second switch unit is closed, the disconnection time of the second timed closing circuit is T4, T4=T3+t2, t2 is the timing duration of the second timed closing circuit.

[0012] Optionally, the control signal module includes a DCS control module and / or an input button, and the first switch unit includes a first switch and a second switch connected in parallel;

[0013] The closing of the first switch is controlled by an opening command from a DCS control module, and the closing of the second switch is controlled by an opening command from an input button module.

[0014] Optionally, the control signal module includes a DCS control module and / or an input button, and the second switch unit includes a third switch and a fourth switch connected in parallel;

[0015] The closing of the third switch is controlled by an off command from the DCS control module, and the closing of the fourth switch is controlled by an off command from the input button module.

[0016] Optionally, the valve control system includes a box body, wherein a plurality of interfaces are provided in the box body, and the plurality of interfaces are used to connect a plurality of the valve control circuit boards;

[0017] A power supply module is provided in the box body, and the power supply module supplies power to the valve control circuit board through the interface.

[0018] Optionally, a detachable cable gland mounting plate is provided in the box body, and a plurality of accommodating spaces are provided above the cable gland mounting plate, and the plurality of accommodating spaces are used to accommodate a plurality of the valve control circuit boards.

[0019] Optionally, the power supply module includes an isolated power supply module.

[0020] Optionally, the isolation voltage of the isolated power supply module is not less than 1500V.

[0021] Optionally, input signals of multiple valve control circuit boards are isolated by optocouplers or relays.

[0022] Optionally, the output signals of the multiple valve control circuit boards are isolated by relays.

[0023] Optionally, the current carrying capacity of the valve opening relay and the valve closing relay is not less than 5A / 250VAC.

[0024] The valve control system provided by the present invention achieves miniaturization of the valve control system by integrating hardware such as a switch unit, a timed closing circuit, and a relay on a valve control circuit board, eliminating the need for discrete electrical components. Furthermore, by using a timed closing circuit to control the output of the relay, the opening and closing of the valve is controlled by the output of the relay, eliminating the need for software programming and being suitable for the nuclear power field. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions in the present invention or the prior art, a brief introduction is given below to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0026] Figure 1 It is a structural diagram of the valve control system provided by the present invention;

[0027] Figure 2 It is a structural schematic diagram of the valve control circuit board provided by the present invention;

[0028] Figure 3 It is one of the schematic diagrams of the box provided by the present invention;

[0029] Figure 4 This is the second schematic diagram of the box provided by the present invention;

[0030] Figure 5 This is the third schematic diagram of the box provided by the present invention;

[0031] Figure 6 This is the fourth schematic diagram of the box provided by the present invention;

[0032] Figure 7 This is a control principle block diagram of the valve control system provided by the present invention;

[0033] Figure 8This is the fifth schematic diagram of the box provided by the present invention. DETAILED DESCRIPTION

[0034] To make the objectives, technical solutions, and advantages of the present invention more clear, the technical solutions of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0035] With the advancement of electronic technology, nuclear power plants are developing at a rapid pace. Digital and electronic technologies are being widely applied, and third-generation nuclear power will be fully digitized. Valve control boxes designed with discrete electrical components or programmable controllers generally suffer from drawbacks such as large size, a single type of control valve, a small number of control valves, and low reliability.

[0036] The valve control system provided by the present invention can reduce the volume of the valve control system, is implemented purely by hardware, does not require programming, and is suitable for the nuclear power field.

[0037] The valve control system of the present invention will be described below with reference to the accompanying drawings.

[0038] Figure 1 This is a schematic diagram of the structure of the valve control system provided by the present invention. Figure 1 As shown, the system 1000 includes: a control signal module 1100 and a valve control circuit board 1200;

[0039] The valve control circuit board 1200 includes a valve opening control module 1210 and a valve closing control module 1220 in parallel;

[0040] The valve opening control module 1210 includes a first switch unit 1211, a first timed closing circuit 1212, and a valve opening relay 1213. One end of the first timed closing circuit 1212 is connected to the first switch unit 1211, and the other end of the first timed closing circuit 1212 is connected to the valve opening relay 1213. The closing of the first switch unit 1211 is controlled by an opening command from the control signal module 1100. The start time T1 of the first timed closing circuit 1212 is the time when the first switch unit 1211 is closed, and the disconnection time of the first timed closing circuit 1212 is T2, where T2 = T1 + t1, and t1 is the timing duration of the first timed closing circuit 1212.

[0041] The valve closing control module 1220 includes a second switch unit 1221, a second timed closing circuit 1222 and a valve closing relay 1223, one end of the second timed closing circuit 1222 is connected to the second switch unit 1221, and the other end of the second timed closing circuit 1222 is connected to the valve closing relay 1223; the closing of the second switch unit 1221 is controlled by the closing command from the control signal module 1100; wherein, the starting time T3 of the second timed closing circuit 1222 is the time when the second switch unit 1221 is closed, and the disconnection time of the second timed closing circuit 1222 is T4, T4=T3+t2, t2 is the timing duration of the second timed closing circuit 1222.

[0042] Optionally, a valve control circuit board 1200 can be used as an independent valve controller, which is the core component of a miniaturized valve control box and adopts a pure hardware circuit design without programmable devices.

[0043] Optionally, the first timer-off circuit 1212 may be a 555 timing circuit.

[0044] Optionally, the timing duration of the first time-off circuit 1212 can be set to 10 seconds.

[0045] Optionally, the timing duration of the first timer-off circuit 1212 may be set based on user input.

[0046] Optionally, a knob may be provided to receive user input to set the timing duration of the first timed closing circuit 1212 .

[0047] Optionally, the second timer-off circuit 1222 may be a 555 timing circuit.

[0048] Optionally, the timing duration of the second timer-off circuit 1222 can be set to 10 seconds.

[0049] Optionally, the timing duration of the second timer-off circuit 1222 may be set based on user input.

[0050] Optionally, a knob may be provided to receive user input to set the timing duration of the second timed closing circuit 1222 .

[0051] Optionally, the valve opening control module 1210 can receive an opening command from the control signal module 1100, and at this time when the first timed closing circuit 1212 has not reached the timing time and there is no valve closing relay output, the valve opening relay 1213 is closed and self-locked, and the first timed closing circuit 1212 is started. When the valve opening feedback is received (starting from T1) for about 10 seconds (the timing length of the first timed closing circuit 1212 can be set by the knob), the first timed closing circuit 1212 is disconnected, the valve opening relay stops outputting, and the valve opening execution is completed.

[0052] Optionally, the valve closing control module 1220 can receive a closing command from the control signal module 1100, and at this time when the second timed closing circuit 1222 has not reached the timing time and there is no valve opening relay output, the valve closing relay 1223 is closed and self-locked, and the second timed closing circuit 1222 is started. When the valve closing feedback is received (starting from T3) for about 10 seconds (the timing length of the second timed closing circuit 1222 can be set by the knob), the second timed closing circuit 1222 is disconnected, the valve closing relay 1223 stops outputting, and the valve closing execution is completed.

[0053] Optionally, the valve control circuit board 1200 is a core component of a miniaturized valve control system, which adopts a pure hardware circuit design without programmable devices.

[0054] The valve control system provided by the present invention achieves miniaturization of the valve control system by integrating hardware such as a switch unit, a timed closing circuit, and a relay on a valve control circuit board, eliminating the need for discrete electrical components. Furthermore, by using a timed closing circuit to control the output of the relay, the opening and closing of the valve is controlled by the output of the relay, eliminating the need for software programming and being suitable for the nuclear power field.

[0055] Optionally, the control signal module 1100 includes a DCS control module and / or an input button, and the first switch unit 1211 includes a first switch and a second switch connected in parallel;

[0056] The closing of the first switch is controlled by an opening command from a DCS control module, and the closing of the second switch is controlled by an opening command from an input button module.

[0057] Optionally, the control signal module 1100 includes a DCS control module and / or an input button, and the second switch unit 1221 includes a third switch and a fourth switch connected in parallel;

[0058] The closing of the third switch is controlled by an off command from the DCS control module, and the closing of the fourth switch is controlled by an off command from the input button module.

[0059] Optionally, the DCS control module may receive a control signal from other devices or systems through wired or wireless communication, and the control signal may be used to instruct the valve control system to control the valve to open or close.

[0060] Optionally, when the control signal instructs the valve control system to control the valve to open, the control signal module 1100 may send an opening command to the valve opening control module 1210 .

[0061] Optionally, when the control signal instructs the valve control system to control the valve to close, the control signal module 1100 may send a closing command to the valve opening control module 1220 .

[0062] Optionally, the input buttons may include an on button and / or an off button.

[0063] Optionally, when the user presses the open button, the control signal module 1100 may send an open command to the valve open control module 1210 .

[0064] Optionally, when the user presses the close button, the control signal module 1100 may send a close command to the valve close control module 1220 .

[0065] Figure 2 This is a schematic diagram of the structure of the valve control circuit board provided by the present invention. Figure 2 As shown, the control signal module 1100 may include a DCS control module and / or an input button, the first switch unit 1211 may include a first switch and a second switch connected in parallel, and the second switch unit 1221 may include a third switch and a fourth switch connected in parallel;

[0066] Optionally, when the valve opening control module 1210 receives an opening command from the DCS control module, the first switch is closed;

[0067] Optionally, when the valve opening control module 1210 receives an opening command from an input button, the second switch is closed;

[0068] Optionally, when the valve closing control module 1220 receives a closing command from the DCS control module, the third switch is closed;

[0069] Optionally, when the valve closing control module 1220 receives a closing command from an input button, the third switch is closed;

[0070] Optionally, in order to avoid the signal of the DCS control module being discontinuous or the input button being unable to be kept pressed for a long time, the switch corresponding to the valve opening relay 1213 can be closed at the moment when the first switch is closed or the second switch is closed, that is, when the valve opening relay needs to start outputting, to ensure that the valve opening relay 1213 can continue to output within the timing time period of the first timing closing circuit 1212.

[0071] Optionally, to prevent discontinuity of the DCS control module's signal or the inability to maintain a long press of the input button, the switch corresponding to the valve close relay 1223 may be closed at the moment the third or fourth switch is closed, i.e., the moment the valve close relay is required to begin outputting, to ensure that the valve close relay 1223 can continue outputting within the timed period of the second timed-off circuit 1222. Specifically, the valve open control module 1210 may receive an open command from the DCS control module and / or the input button, and if the first timed-off circuit 1212 has not reached its timed duration and the valve close relay is not outputting, the switch corresponding to the valve open relay 1213 is closed and self-locked, and the first timed-off circuit 1212 is activated. After receiving valve open feedback (starting from T1) for approximately 10 seconds (the timed duration of the first timed-off circuit 1212 can be set via the knob), the first timed-off circuit 1212 is disconnected, the switch corresponding to the valve open relay 1213 is disconnected, the valve open relay stops outputting, and the valve opening operation is completed.

[0072] Among them, the valve closing control module 1220 can receive a closing command from the DCS control module and / or the input button, and at this time when the second timed closing circuit 1222 has not reached the timing time and there is no valve opening relay output, the switch corresponding to the valve closing relay 1223 is closed and self-locked, and the second timed closing circuit 1222 is started. When the valve closing feedback is received (starting from T3) for about 10 seconds (the timing length of the second timed closing circuit 1222 can be set by the knob), the second timed closing circuit 1222 is disconnected, the switch corresponding to the valve closing relay 1223 is disconnected, the valve closing relay 1223 stops outputting, and the valve closing execution is completed.

[0073] This invention uses an electronic board to integrate protection, delay, and valve drive functions, replacing discrete electrical components. Without the use of programming devices, hardware circuits are used to implement logic control functions, achieving a high degree of localization and also being applicable to various specialized fields such as nuclear power.

[0074] Optionally, the valve control system includes a box body, wherein a plurality of interfaces are provided in the box body, and the plurality of interfaces are used to connect a plurality of the valve control circuit boards 1200;

[0075] A power supply module is provided in the box body, and the power supply module supplies power to the valve control circuit board 1200 through the interface.

[0076] In the present invention, an electronic board is used to integrate functions such as power supply, protection, delay, and valve drive, replacing discrete electrical components to achieve miniaturization of the valve control system.

[0077] Figure 3This is one of the schematic diagrams of the box provided by the present invention, such as Figure 3 As shown, the box size can be 120mm (height) × 230mm (width) × 110mm (depth).

[0078] Optionally, the box body may be made of 304L stainless steel with a thickness of 1.2 mm.

[0079] Optionally, the door of the box body can be made of aluminum plate with matte oxidized wire drawing treatment, installed with organic glass windows, and fastened to the box body with stainless steel captive screws.

[0080] Optionally, a fixing plate for fixing the valve control circuit board is fastened to the box body using stainless steel countersunk screws.

[0081] Optionally, Figure 4 This is the second schematic diagram of the box provided by the present invention, as shown in FIG. Figure 4 As shown, when the user replaces, disassembles or assembles the valve control circuit board 1200 , the user can open the box door and pull out the valve control circuit board 1200 .

[0082] This invention utilizes a universal and modular design. A single board (valve control circuit board 1200) integrates common valve control functions, such as fire dampers and smoke exhaust valves. Replacement requires only the removal of the corresponding board, facilitating maintenance and replacement. Furthermore, its compact design increases the number of valve control paths while reducing the size of the control box.

[0083] Optionally, a detachable cable gland mounting plate is provided in the box body, and a plurality of accommodating spaces are provided above the cable gland mounting plate, and the plurality of accommodating spaces are used to accommodate a plurality of the valve control circuit boards 1200 .

[0084] Figure 5 This is the third schematic diagram of the box provided by the present invention, as shown in FIG. Figure 5 Shown is a removable gland mounting plate at the bottom of the box, which has multiple glands on it.

[0085] Figure 6 This is the fourth schematic diagram of the box provided by the present invention, as shown in FIG. Figure 6 As shown, there are multiple accommodating spaces above the cable gland mounting plate, and the multiple accommodating spaces are used to accommodate multiple valve control circuit boards 1200.

[0086] Optionally, the power supply module includes an isolated power supply module.

[0087] Optionally, the power supply uses an isolated power module with EMC certification.

[0088] Optionally, the isolation voltage of the isolated power supply module is not less than 1500V.

[0089] In the present invention, the isolation voltage is not less than 1500V, which can improve the electromagnetic compatibility and anti-interference ability of the equipment.

[0090] Optionally, the input signals of the multiple valve control circuit boards 1200 are isolated by optocouplers or relays.

[0091] Optionally, the external input signals of the multiple valve control circuit boards 1200 can be isolated using optocouplers or relays.

[0092] In the present invention, by isolating the input signal, when a certain valve control circuit board encounters a high-voltage environment, other valve control circuit boards can be effectively protected.

[0093] Optionally, the output signals of the multiple valve control circuit boards 1200 are isolated by relays.

[0094] Optionally, the current carrying capacity of the valve opening relay 1213 and the valve closing relay 1223 is not less than 5A / 250VAC.

[0095] Optionally, the brand of the control relay in the valve control system may be Omron.

[0096] Optionally, the current carrying capacity of the control relay in the valve control system is not less than 5A / 250VAC.

[0097] In one embodiment, taking eight valve control circuit boards (a1, a2, a3, a4, a5, a6, a7, and a8) provided in the box as an example, Figure 7 This is a control principle block diagram of the valve control system provided by the present invention, such as Figure 7 As shown, an external power supply can power the valve control system via power modules 1 and 2, with a circuit breaker provided between the external power supply and the power modules. The DCS control module can receive control signals from other devices or systems via wired or wireless communication. These control signals can be used to instruct the valve control system to open or close the valves. For example, a1, a2, a3, a4, a5, a6, and a7 can be instructed to open the valve, and a8 can be instructed to close the valve; or a1, a2, a3, a4, and a5 can be instructed to close the valve, and a6, a7, and a8 can be instructed to open the valve. Input buttons can receive user input, and the valve control system can determine which valves to open and which to close based on the user input. For example, if a user presses the buttons corresponding to a1, a2, a3, and a4, it indicates that a1, a2, a3, and a4 control the valves to open. If a user presses the buttons corresponding to a5, a6, a7, and a8, it indicates that a5, a6, a7, and a8 control the valves to close.

[0098] Optionally, after the valve control system determines that each valve needs to be controlled to be opened or closed, the open or closed state of each valve may be sent to the valve execution module so that the valve execution module executes the opening or closing of the valve.

[0099] Figure 8 This is the fifth schematic diagram of the box provided by the present invention, as shown in FIG. Figure 8 As shown, taking the case where 8 valve control circuit boards (a1, a2, a3, a4, a5, a6, a7, and a8) are provided in the box, 8 buttons can be provided on the box (one-to-one corresponding to the 8 valve control circuit boards a1, a2, a3, a4, a5, a6, a7, and a8), and each button corresponds to 2 indicator lights (type i light and type ii light, corresponding to the valve open state and valve closed state respectively); for example, when the user presses the button corresponding to a1, a2, a3, and a4, it indicates that a1 is on. , a2, a3, and a4 control the valve to open, the i-type lights next to the buttons corresponding to a1, a2, a3, and a4 light up, and the user determines that the valves controlled by a1, a2, a3, and a4 are in the open state; for example, if the user presses the buttons corresponding to a5, a6, a7, and a8, it indicates that a5, a6, a7, and a8 control the valve to close, the ii-type lights next to the buttons corresponding to a5, a6, a7, and a8 dim, and the user determines that the valves controlled by a5, a6, a7, and a8 are in the closed state.

[0100] Through the description of the above embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus a necessary general hardware platform, or of course, by hardware. Based on this understanding, the essence of the above technical solution or the part that contributes to the existing technology can be embodied in the form of a software product. The computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a magnetic disk, an optical disk, etc., and includes a number of instructions for enabling a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or certain parts of the embodiments.

[0101] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A valve control system, characterized in that: include: Control signal module and valve control circuit board; The valve control circuit board includes a parallel valve opening control module and a valve closing control module; The valve opening control module includes a first switch unit, a first timed closing circuit, and a valve opening relay. One end of the first timed closing circuit is connected to the first switch unit, and the other end of the first timed closing circuit is connected to the valve opening relay. The closing of the first switch unit is controlled by an opening command from the control signal module. The start time T1 of the first timed closing circuit is the time when the first switch unit is closed, and the disconnect time of the first timed closing circuit is T2, where T2 = T1 + t1, and t1 is the timing duration of the first timed closing circuit. The valve closing control module includes a second switch unit, a second timed closing circuit, and a valve closing relay. One end of the second timed closing circuit is connected to the second switch unit, and the other end of the second timed closing circuit is connected to the valve closing relay. The closing of the second switch unit is controlled by a closing command from the control signal module. The start time T3 of the second timed closing circuit is the time when the second switch unit is closed, and the disconnect time of the second timed closing circuit is T4, where T4=T3+t2, and t2 is the timing duration of the second timed closing circuit. The control signal module includes a DCS control module and / or an input button, and the first switch unit includes a first switch and a second switch connected in parallel; The closing of the first switch is controlled by an opening command from a DCS control module, and the closing of the second switch is controlled by an opening command from an input button module; The control signal module includes a DCS control module and / or an input button, and the second switch unit includes a third switch and a fourth switch connected in parallel; The closing of the third switch is controlled by an off command from the DCS control module, and the closing of the fourth switch is controlled by an off command from the input button module.

2. The valve control system according to claim 1, characterized in that: The valve control system includes a box body, wherein a plurality of interfaces are provided in the box body, and the plurality of interfaces are used to connect a plurality of the valve control circuit boards; A power supply module is provided in the box body, and the power supply module supplies power to the valve control circuit board through the interface.

3. The valve control system according to claim 2, characterized in that: A detachable cable gland mounting plate is provided in the box body, and a plurality of accommodating spaces are provided above the cable gland mounting plate. The plurality of accommodating spaces are used to accommodate a plurality of the valve control circuit boards.

4. The valve control system according to claim 2, characterized in that: The power supply module includes an isolated power supply module.

5. The valve control system according to claim 4, characterized in that: The isolation voltage of the isolated power supply module is not less than 1500V.

6. The valve control system according to claim 2, characterized in that: The input signals of multiple valve control circuit boards are isolated by optocouplers or relays.

7. The valve control system according to claim 2, characterized in that: The output signals of multiple valve control circuit boards are isolated by relays.

8. The valve control system according to claim 1, characterized in that: The current carrying capacity of the valve opening relay and the valve closing relay is not less than 5A / 250VAC.

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