Intelligent far-end drainage control system

Through the intelligent remote drainage control system, cloud control and mobile terminals are used to realize remote control and automatic analysis of water pumps, the problems of high operating costs and on-duty risks of drainage pumps on site overhaul of the power plant are solved, and an efficient unattended operation mode is achieved.

CN222232887UActive Publication Date: 2024-12-24SOUTH-TO-NORTH WATER DIVERSION (JIANGSU) DIGITAL INTELLIGENCE TECH CO LTD
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Patent Information

Application Number
CN202420318510.2
Authority / Receiving Office
CN · China
Patent Type
Utility models(China)
Current Assignee / Owner
Filing Date
2024-02-21
Publication Date
2024-12-24
Estimated Expiration
2034-02-21

AI Technical Summary

Technical Problem

The drainage pump on the power plant overhaul site lacks the support of automation systems, and the operating conditions and water level data need to be observed on the spot, resulting in high operating costs and high night duty pressure, which poses a risk of duty.

Method used

Design an intelligent remote drainage control system, including control cabinets, water pumps, water level meters, cloud management and control systems and mobile terminals, realize two-way communication through 4G networks and wireless networks, support remote control and video surveillance, integrate high-performance IO modules and alarms Indication circuit can automatically collect and analyze water pump operation data, realizing automatic start-stop and fault alarms.

Benefits of technology

The investment in water pump operation and duty personnel has been reduced, production and operation efficiency has been improved, and the operation mode of "unmanned duty and fewer duty" has been realized, providing a theoretical and practical basis for the construction of smart pump stations.

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Abstract

The utility model relates to the technical field of intelligent far-end drainage control systems, in particular to an intelligent far-end drainage control system which comprises a control cabinet, a water pump, a water level gauge, a cloud management and control system and a mobile terminal. One side of the control cabinet is electrically connected with the water pump and the water level gauge, and the other side of the control cabinet is in two-way communication with the cloud management and control system through a 4G network; the cloud management and control system is in two-way communication with the mobile terminal and the camera; the camera, the water pump and the water level gauge are arranged at the drainage runner; four groups of water pumps are arranged, and two groups of water level gauges and two groups of cameras are arranged. The design can reduce the investment of water pump operation personnel and improve the production and operation efficiency. And the system is applied to small and medium-sized gate stations, so that an unattended and few-person on-duty operation mode is realized, and a theoretical and practical basis is provided for exploring the construction of an intelligent pump station.
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Description

Technical Field

[0001] The utility model relates to the technical field of intelligent remote drainage control systems, in particular to an intelligent remote drainage control system. Background Art

[0002] The following problems exist in the operation of drainage pumps at power plant overhaul sites: (1) The operation of the pumps lacks support from an automated system, and the operating conditions, water level data, and on-site conditions need to be observed on-site; (2) Pump inspection personnel need to arrive at the site to observe the water level and check the operation of the pumps, resulting in high operating costs; (3) The operation of the pumps needs to be monitored at night, and the inspection pressure on the operating personnel is high, with certain risks incurred during duty. Utility Model Content

[0003] In order to overcome the existing deficiencies, the utility model provides an intelligent remote drainage control system, which includes 4 water pump interfaces, which respectively collect the operation signals and overheating signals of the 4 water pumps, have the function of controlling the tripping of the main circuit breaker, and can switch between on-site and remote control modes; the system can be connected to two water level meters, and the access method is 4-20mA analog input; it supports the collection of the three-phase total current of the motor operation, and the collection method is 4-20mA analog input; it supports the collection of insulation monitor data and alarm signals in the control cabinet, and the communication method is Modbus 485; the wireless camera uploads the video image to the cloud platform via the wireless network.

[0004] The technical solution adopted by the utility model to solve its technical problems is: an intelligent remote drainage control system, including a control cabinet, a water pump, a water level meter, a cloud management and control system and a mobile terminal; one side of the control cabinet is electrically connected to the water pump and the water level meter, and the other side communicates bidirectionally with the cloud management and control system through a 4G network; the cloud management and control system communicates bidirectionally with the mobile terminal and the camera; the camera, the water pump and the water level meter are arranged at the drainage flow channel; a conversion switch, a signal light and a button are provided on the cabinet door of the control cabinet, and the interior includes a switching power supply, an intelligent remote control terminal, a high-performance IO module, a main power supply circuit and a water pump control circuit; the switching power supply is connected to the intelligent remote control terminal and the high-performance IO module; the intelligent remote control terminal is electrically connected to the high-performance IO module, the current transmitter, the water level meter and the cloud management and control system; the high-performance IO module is connected to a relay, one end of the main power supply circuit is connected to a power supply, and the other end is connected to a water pump through an AC contactor and a thermal relay; the water pump control circuit includes a start-stop operation control circuit and an alarm indication circuit; the alarm indication circuit is connected to a signal light, and the start-stop operation control circuit is connected to a conversion switch and a button.

[0005] According to another embodiment of the utility model, the intelligent remote control terminal further includes a 485\232 communication module, an RS485 communication module, a DC analog input module, a working power supply module, a door control module and an output module; the DC analog input module is connected to the water level meter and the current transmitter TA-A, the current transmitter TA-B, and the current transmitter TA-C; the RS485 communication module wirelessly communicates with the cloud control system; the 485\232 communication module is connected to a high-performance IO module; the door control module is connected to the conversion switch SA1 and the molded case switch DL; the output module is connected to the circuit breaker shunt KA9.

[0006] According to another embodiment of the utility model, the high-performance IO module is further connected to the AC contactor KM1-4 and the relay ZJ1-4 through the switch input module, connected to the relay KA1-8 through the switch output, and connected to the intelligent remote control terminal through the RS485 module.

[0007] According to another embodiment of the utility model, it further includes that the main power supply circuit module includes an AC380V power supply, a current transmitter TA-A, a current transmitter TA-B, a current transmitter TA-C, an AC contactor KM1, an AC contactor KM2, an AC contactor KM3, an AC contactor KM4, a thermal relay FR1, a thermal relay FR2, a thermal relay F3, a thermal relay FR4 and a water pump M1, a water pump M2, a water pump M3 and a water pump M4; the three phases of the AC380V power supply are respectively connected to the current transmitter TA-A, the current transmitter TA-B and the current transmitter TA-C through the molded case switch DL, and are respectively connected to the thermal relay FR1 through the AC contactor KM1 to control the water pump M1, the AC contactor KM2 is connected to the thermal relay FR2 to control the water pump M2, the AC contactor KM3 is connected to the thermal relay FR3 to control the water pump M3, and the AC contactor KM4 is connected to the thermal relay FR4 to control the water pump M5.

[0008] According to another embodiment of the utility model, the start-stop operation control circuit is further included, one end of the conversion switch SA1 is connected to the button SB11, the button SB21, the button SB31, and the button SB41, and the other end is connected to the circuit breaker KA1, the circuit breaker KA2, the circuit breaker KA3, and the circuit breaker KA4; the button SB11 and the circuit breaker KA1 are connected in parallel with the AC contactor KM1, and the AC contactor KM1 coil, the thermal relay FR1 relay KA2, and the button SB12 are connected together; the button SB21 and the circuit breaker are connected to the AC contactor KM1 coil, the thermal relay FR1 relay KA2, and the button SB12; The AC contactor KM2 is connected in parallel at both ends of the circuit breaker KA2, and the AC contactor KM2 coil, thermal relay FR2, relay KA4, and button SB22 are connected together; the button SB31 and the circuit breaker KA3 are connected in parallel with the AC contactor KM3, and the AC contactor KM3 coil, thermal relay FR3, relay KA6, and button SB32 are connected together; the button SB41 and the circuit breaker KA4 are connected in parallel with the AC contactor KM4 coil, thermal relay FR4, relay KA7, and button SB42.

[0009] According to another embodiment of the utility model, it further includes that the alarm indication circuit is connected in series with the indicator light HL11 through the AC contactor KM1, the thermal relay FR1 is connected in series with the relay ZJ1 coil, the relay ZJ1 is connected in series with the indicator light HL12, the AC contactor KM2 is connected in series with the indicator light HL21, the thermal relay FR2 is connected in series with the relay ZJ2 coil, the relay ZJ2 is connected in series with the indicator light HL22, the AC contactor KM3 is connected in series with the indicator light HL31, the thermal relay FR3 is connected in series with the relay ZJ3 coil, the relay ZJ3 is connected in series with the indicator light HL32, the AC contactor KM4 is connected in series with the indicator light HL41, the thermal relay FR4 is connected in series with the relay ZJ4 coil, and the relay ZJ14 is connected in series with the indicator light HL42.

[0010] The beneficial effect of the utility model is to reduce the input of water pump operation personnel and improve production and operation efficiency. For social promotion, the application of this system in small and medium-sized gate stations can realize the "unmanned and less-staffed" operation mode, providing a theoretical and practical basis for exploring the construction of smart pump stations. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] The utility model is further described below in conjunction with the accompanying drawings and embodiments.

[0012] Figure 1 It is a structural schematic diagram of the utility model;

[0013] Figure 2 It is a schematic diagram of the structure of the control cabinet;

[0014] Figure 3 It is the schematic diagram of the intelligent remote control terminal;

[0015] Figure 4 This is the schematic diagram of the high-performance IO module;

[0016] Figure 5 It is the main power supply circuit schematic;

[0017] Figure 6 It is the start-stop operation control circuit diagram;

[0018] Figure 7 It is the alarm indication circuit diagram;

[0019] Figure 8 It is a switching power supply control circuit.

[0020] In the figure, 1, control cabinet, 2, water pump, 3, water level meter, 4, cloud management and control system, 5, mobile terminal, 6, camera. DETAILED DESCRIPTION

[0021] like Figure 1 It is a structural schematic diagram of the utility model, an intelligent remote drainage control system, including a control cabinet 1, a water pump 2, a water level meter 3, a cloud management and control system 4 and a mobile terminal 5; one side of the control cabinet 1 is electrically connected to the water pump 2 and the water level meter 3, and the other side communicates with the cloud management and control system 4 through a 4G network; the cloud management and control system 4 communicates with the mobile terminal 5 and the camera 6 in a two-way manner; the camera 6, the water pump 2, and the water level meter 3 are arranged at the drainage channel; the water pump 2 is provided with four groups, and the water level meter 3 and the camera 6 are provided with two groups respectively; the cabinet door of the control cabinet 1 is provided with a conversion switch, a signal light and a button, and the interior includes a switch Turn off the power supply, intelligent remote control terminal, high-performance IO module, main power supply circuit, and water pump control circuit; the switch power supply is connected to the intelligent remote control terminal and the high-performance IO module; the intelligent remote control terminal is electrically connected to the high-performance IO module, the current transmitter, the water level meter 3 and the cloud management and control system 4; the high-performance IO module is connected to the relay, one end of the main power supply circuit is connected to the power supply, and the other end is connected to the water pump through the AC contactor and the thermal relay; the water pump control circuit includes a start-stop operation control circuit and an alarm indication circuit; the alarm indication circuit is connected to the signal light, and the start-stop operation control circuit is connected to the conversion switch and the button.

[0022] Specifically, the intelligent remote control terminal has interfaces for 4 water pumps 2, and supports motors within the performance parameter range of 7.5KW and rated current 16.8A; the cloud service is built on the cloud management and control system 4, mainly including data interaction with the intelligent terminal, collecting images from the camera 6, and data interaction with the mobile terminal 5; the mobile terminal 5 can use a mobile phone APP, and the functions it can have include water pump 2 operation data and camera image display, remote control of water pump 2, historical data query, parameter setting, etc. Specifically, the mobile terminal 5 collects and displays data such as water level, current, and operation signals. When the instruction is issued, the contactor is actuated and the water pump 2 is not started at the same time, there should be no water pump 2 operation indication. Only when the water pump 2 starts normally can the operation signal be displayed, various alarms can be monitored, and push notifications can be accepted. The push notification method is to send alarm information and alarm sounds in the APP, and the operator pushes text messages to the user's mobile phone, communicate with the insulation monitor of the control cabinet 1, and collect and display the insulation resistance value and insulation resistance alarm signal of the water pump 2 motor.

[0023] According to another embodiment of the utility model, the intelligent remote control terminal further includes a 485\232 communication module, an RS485 communication module, a DC analog input module, a working power supply module, a door control module and an output module; the DC analog input module is connected to the water level meter 3 current transmitter TA-A, current transmitter TA-B, and current transmitter TA-C; the RS485 communication module wirelessly communicates with the cloud control system; the 485\232 communication module is connected to a high-performance IO module; the door control module is connected to the conversion switch SA1 and the molded case switch DL; the output module is connected to the circuit breaker shunt KA9.

[0024] According to another embodiment of the utility model, it further includes that the high-performance IO module is connected to the AC contactor KM1-4 and the relay ZJ1-4 through the switch quantity input module, connected to the relay KA1-8 through the switch quantity output, and connected to the intelligent remote control terminal through the RS485 module, and is used to collect data information of the AC contactor KM1-4, the relay ZJ1-4 and the relay KA1-8, the relay KA1-8 is used to confirm the start and stop of the water pump 2, the AC contactor KM1-4 is used to confirm the operation signal of the water pump 2, and the relay ZJ1-4 is used to confirm the fault signal of the water pump 2.

[0025] According to another embodiment of the utility model, it further includes that the main power supply circuit module includes an AC380V power supply, a current transmitter TA-A, a current transmitter TA-B, a current transmitter TA-C, an AC contactor KM1, an AC contactor KM2, an AC contactor KM3, an AC contactor KM4, a thermal relay FR1, a thermal relay FR2, a thermal relay F3, a thermal relay FR4 and a water pump M1, a water pump M2, a water pump M3 and a water pump M4; the three phases of the AC380V power supply are respectively connected to the current transmitter TA-A, the current transmitter TA-B and the current transmitter TA-C through the molded case switch DL, and are respectively connected to the thermal relay FR1 through the AC contactor KM1 to control the water pump M1, the AC contactor KM2 is connected to the thermal relay FR2 to control the water pump M2, the AC contactor KM3 is connected to the thermal relay FR3 to control the water pump M3, and the AC contactor KM4 is connected to the thermal relay FR4 to control the water pump M5.

[0026] According to another embodiment of the utility model, the start-stop operation control circuit is further included, one end of the conversion switch SA1 is connected to the button SB11, the button SB21, the button SB31, and the button SB41, and the other end is connected to the circuit breaker KA1, the circuit breaker KA2, the circuit breaker KA3, and the circuit breaker KA4; the button SB11 and the circuit breaker KA1 are connected in parallel with the AC contactor KM1, and the AC contactor KM1 coil, the thermal relay FR1 relay KA2, and the button SB12 are connected together; the button SB21 and the circuit breaker are connected to the AC contactor KM1 coil, the thermal relay FR1 relay KA2, and the button SB12; The AC contactor KM2 is connected in parallel at both ends of the circuit breaker KA2, and the AC contactor KM2 coil, thermal relay FR2, relay KA4, and button SB22 are connected together; the button SB31 and the circuit breaker KA3 are connected in parallel with the AC contactor KM3, and the AC contactor KM3 coil, thermal relay FR3, relay KA6, and button SB32 are connected together; the button SB41 and the circuit breaker KA4 are connected in parallel with the AC contactor KM4 coil, thermal relay FR4, relay KA7, and button SB42.

[0027] Specifically, in the start-stop operation control circuit, button SB11 is used to manually control the start and stop of the first group of water pumps 2, button SB21 is used to manually control the start and stop of the second group of water pumps 2, button SB31 is used to manually control the start and stop of the third group of water pumps 2, and button SB41 is used to manually control the start and stop of the fourth group of water pumps 2; the circuit breakers KA1, KA2, KA3, and KA4 are respectively used to automatically control the start and stop of the four groups of water pumps 2.

[0028] According to another embodiment of the utility model, it further includes that the alarm indication circuit is connected in series with the indicator light HL11 through the AC contactor KM1, the thermal relay FR1 is connected in series with the relay ZJ1 coil, the relay ZJ1 is connected in series with the indicator light HL12, the AC contactor KM2 is connected in series with the indicator light HL21, the thermal relay FR2 is connected in series with the relay ZJ2 coil, the relay ZJ2 is connected in series with the indicator light HL22, the AC contactor KM3 is connected in series with the indicator light HL31, the thermal relay FR3 is connected in series with the relay ZJ3 coil, the relay ZJ3 is connected in series with the indicator light HL32, the AC contactor KM4 is connected in series with the indicator light HL41, the thermal relay FR4 is connected in series with the relay ZJ4 coil, and the relay ZJ14 is connected in series with the indicator light HL42.

[0029] Specifically, the alarm indication circuit displays the operation and fault signals of four groups of water pumps 2 through indicator lights. Indicator lights HL11 and HL12 are used to display the operation and fault of the first group of water pumps 2, indicator lights HL21 and HL22 are used to display the operation and fault of the second group of water pumps 2, indicator lights HL31 and HL32 are used to display the operation and fault of the third group of water pumps 2, and indicator lights HL41 and HL42 are used to display the operation and fault of the fourth group of water pumps 2.

[0030] In the specific operation process, the system functions include collection and monitoring of the mobile terminal 5, equipment control, recording and statistics, image monitoring, parameter configuration, and current analysis and water level analysis of the intelligent remote end based on edge computing. That is, in addition to collecting and processing data, the main function of the edge end is data judgment and analysis. It can automatically start and stop the water pump 2 and push an alarm when an abnormality or failure occurs. For example: during operation, when the current exceeds the thermal relay current or exceeds a certain proportion of the set value, and the thermal relay does not operate, the water pump 2 should be stopped automatically. After the motor starts and the current value stabilizes, when the current is missing or unbalanced, there should be an alarm, and the water pump 2 should be stopped automatically. The percentage of the unbalanced value can be set; when the water level reaches the upper limit or the upper-high limit, the system should automatically start the water pump 2, and issue an alarm and equipment action prompt. The upper limit and the upper-high limit can be set to start the pump. Number of units. When the water level reaches the lower limit, all water pumps 2 are stopped (this function can be turned off or on). When the water level difference is greater than the set value, the pump should be stopped or the pump should be prohibited from starting (this function can be turned off or on). In the automatic pump start program, the smaller value of the two water level gauge 3 data is taken as the upper limit action value. In the automatic pump stop program, the larger value of the two water level data is taken as the lower limit action value. Automatically detect the operating status and communication status of the water level sensor. When there are abnormal data of the water level gauge 3, water level sensor failure, communication with the water level gauge 3 and other failures, a corresponding alarm should be issued. When the equipment communication is interrupted, a corresponding alarm should be issued. When there is no action after the control command is issued, a corresponding alarm should be issued. When the automatic pump start program is executed, the water pump 2 does not start normally, a fault alarm should be issued. When the automatic pump stop program is executed, the water pump 2 does not stop normally, the circuit breaker should be tripped and a fault alarm should be issued.

[0031] The insulation monitor can monitor the insulation resistance of the motor in real time when the motor is shut down. When the insulation resistance is lower than the set value, an alarm will be sounded through an alarm light or buzzer. At the same time, the edge gateway will collect the alarm signal and send it to the cloud. Finally, an alarm prompt will be issued through the APP and an alarm text message will be pushed.

[0032] When the four water pumps 2 are turned on at the same time and the water level does not drop within a certain period of time, an alarm should be issued. The interval time and water level change difference for judgment can be selected. The preset value and time can be set through the APP.

[0033] The intelligent remote drainage control system based on edge computing will provide a new idea for the "unattended" operation mode, break through the limitations of traditional LAN, and use mobile terminals 5, cloud management and control systems 4, and edge gateways to build a complete intelligent remote monitoring platform for water pumps 2. Through water level meters 3 and cameras 6, the operating conditions, flow channel water levels, alarm status, video image information, etc. of water pumps 2 can be monitored in real time, and the start and stop of water pumps 2 can be remotely controlled. At the same time, edge computing can be used to analyze operating data and water level data in real time.

[0034] The above description is only illustrative rather than restrictive of the present invention. Those skilled in the art will understand that many modifications, changes or equivalents may be made without departing from the spirit and scope defined by the appended claims, but all will fall within the scope of protection of the present invention.

Claims

1. An intelligent remote drainage control system, characterized in that: The invention comprises a control cabinet (1), a water pump (2), a water level gauge (3), a cloud management and control system (4) and a mobile terminal (5); one side of the control cabinet (1) is electrically connected to the water pump (2) and the water level gauge (3), and the other side communicates bidirectionally with the cloud management and control system (4) via a 4G network; the cloud management and control system (4) communicates bidirectionally with the mobile terminal (5) and the camera (6); the camera (6), the water pump (2) and the water level gauge (3) are arranged at the drainage channel; the water pump (2) is provided with four groups, and the water level gauge (3) and the camera (6) are provided with two groups respectively; a conversion switch, a signal light and a button are provided on the cabinet door of the control cabinet (1), and the inner The device comprises a switching power supply, an intelligent remote control terminal, a high-performance IO module, a main power supply circuit, and a water pump control circuit; the switching power supply is connected to the intelligent remote control terminal and the high-performance IO module; the intelligent remote control terminal is electrically connected to the high-performance IO module, the current transmitter, the water level meter (3) and the cloud management and control system (4); the high-performance IO module is connected to a relay, one end of the main power supply circuit is connected to a power supply, and the other end is connected to a water pump through an AC contactor and a thermal relay; the water pump control circuit comprises a start-stop operation control circuit and an alarm indication circuit; the alarm indication circuit is connected to a signal light, and the start-stop operation control circuit is connected to a conversion switch and a button.

2. The intelligent remote drainage control system according to claim 1 is characterized in that: The intelligent remote control terminal comprises a 485\232 communication module, an RS485 communication module, a DC analog input module, a working power supply module, a box door control module and an output module; the DC analog input module is connected to a water level meter (3) and current transmitters TA-A, TA-B and TA-C; the RS485 communication module communicates wirelessly with a cloud control system; the 485\232 communication module is connected to a high-performance IO module; the box door control module is connected to a conversion switch SA1 and a molded case switch DL; and the output module is connected to a circuit breaker shunt KA9.

3. The intelligent remote drainage control system according to claim 1 is characterized in that: The high-performance IO module is connected to the AC contactor KM1-4 and the relay ZJ1-4 through the switch quantity input module, connected to the relay KA1-8 through the switch quantity output, and connected to the intelligent remote control terminal through the RS485 module.

4. The intelligent remote drainage control system according to claim 1 is characterized in that: The main power supply circuit module includes an AC380V power supply, a current transmitter TA-A, a current transmitter TA-B, a current transmitter TA-C, an AC contactor KM1, an AC contactor KM2, an AC contactor KM3, an AC contactor KM4, a thermal relay FR1, a thermal relay FR2, a thermal relay F3, a thermal relay FR4 and water pumps M1, water pumps M2, water pumps M3 and water pumps M4; the three phases of the AC380V power supply are respectively connected to the current transmitter TA-A, the current transmitter TA-B and the current transmitter TA-C through the molded case switch DL, and are respectively connected to the thermal relay FR1 through the AC contactor KM1 to control the water pump M1, the AC contactor KM2 is connected to the thermal relay FR2 to control the water pump M2, the AC contactor KM3 is connected to the thermal relay FR3 to control the water pump M3, and the AC contactor KM4 is connected to the thermal relay FR4 to control the water pump M5.

5. The intelligent remote drainage control system according to claim 1 is characterized in that: The start-stop operation control circuit is connected to buttons SB11, SB21, SB31 and SB41 at one end of the conversion switch SA1, and is connected to circuit breakers KA1, KA2, KA3 and KA4 at the other end; the button SB11 and circuit breaker KA1 are connected with AC contactor KM1 in parallel at both ends, and the coil of AC contactor KM1, thermal relay FR1, relay KA2 and button SB12 are connected together; the button SB21 and circuit breaker KA2 are connected with AC contactor KM2 in parallel at both ends, and the coil of AC contactor KM2, thermal relay FR2, relay KA4 and button SB22 are connected together; the button SB31 and circuit breaker KA3 are connected with AC contactor KM3 in parallel at both ends, and the coil of AC contactor KM3, thermal relay FR3, relay KA6 and button SB32 are connected together; the button SB41 and circuit breaker KA4 are connected with AC contactor KM4 in parallel at both ends, and the coil of AC contactor KM4, thermal relay FR4, relay KA7 and button SB42 are connected together.

6. The intelligent remote drainage control system according to claim 1, characterized in that: The alarm indication circuit is connected in series with the indicator light HL11 of the AC contactor KM1, the thermal relay FR1 in series with the relay ZJ1 coil, the relay ZJ1 in series with the indicator light HL12, the AC contactor KM2 in series with the indicator light HL21, the thermal relay FR2 in series with the relay ZJ2 coil, the relay ZJ2 in series with the indicator light HL22, the AC contactor KM3 in series with the indicator light HL31, the thermal relay FR3 in series with the relay ZJ3 coil, the relay ZJ3 in series with the indicator light HL32, the AC contactor KM4 in series with the indicator light HL41, the thermal relay FR4 in series with the relay ZJ4 coil, and the relay ZJ14 in series with the indicator light HL42.