Wiring of Chint Moulded Case Circuit Breaker in the Water Pump Power Distribution Box.

 The following is the general wiring method of 

Chint moulded case circuit breaker in the water pump power distribution box:

### Preparation Work

- Ensure that the power distribution box is powered off, and hang a sign that reads "Do not close the switch. Someone is working."

to ensure operational safety.

- Prepare the required tools, such as a screwdriver, wire stripper, etc.

### Main Circuit Wiring

- **Power Inlet**: Connect the three phase wires (usually yellow, green, and red) from the power source end to the inlet terminals of the moulded

 case circuit breaker respectively. These terminals are usually marked as L1, L2, and L3. Note that they should be connected according to the 

corresponding phase sequence to ensure the normal operation of subsequent equipment. When wiring, strip off an appropriate length of the 

insulating layer at the end of the wire first, and then insert the conductor into the wiring hole of the circuit breaker's inlet terminal. Use a screwdriver

 to tighten the wiring screw to ensure a firm connection and good contact, and avoid problems such as overheating caused by looseness.

- **Load Outlet**: Lead out three phase wires from the outlet terminals (marked as T1, T2, T3) of the moulded case circuit breaker and connect 

them to the wiring terminals of the water pump motor. Also, pay attention to the correspondence of the phase sequence and the firmness of the 

wiring. If the water pump motor is also equipped with protection devices such as a thermal relay, then the outlet wire of the moulded case circuit breaker 

should be first connected to the inlet terminal of the thermal relay, and then from the outlet terminal of the thermal relay to the water pump motor.

### Auxiliary Circuit Wiring (if available)

- **Auxiliary Contact Wiring**: Some moulded case circuit breakers are equipped with auxiliary contacts, which are used for signal feedback or 

control circuits. For example, the normally open auxiliary contact can be used to connect to the indicator light circuit. When the circuit breaker is

 closed, the normally open contact closes, and the indicator light turns on, indicating that the circuit is energized. The normally closed auxiliary 

contact can be used to interlock with other protection devices or control circuits. When the circuit breaker trips, the normally closed contact opens,

 triggering the corresponding protection or control action. Connect the connecting wires of the auxiliary contacts to the corresponding control 

circuit terminals according to the design requirements to ensure that the wiring is correct.

### Grounding Wiring

- The casing of the moulded case circuit breaker generally should be grounded to ensure that in case of faults such as electric leakage, the current 

can be safely conducted into the ground to protect the safety of personnel and equipment. Connect the grounding busbar or grounding bar of the

 power distribution box to the grounding terminal of the moulded case circuit breaker through a suitable grounding wire. The grounding terminal

 is usually marked as PE or with a grounding symbol. The grounding connection should be firm and reliable, and the grounding resistance should 

meet the relevant standard requirements.

After the wiring is completed, check again whether all the wiring is firm and correct. Only after confirming that there are no errors can you close 

the main power switch of the power distribution box, conduct a power-on test on the circuit, observe the operation of the moulded case circuit breaker

 and the water pump. If there is any abnormality, power off immediately for inspection. 

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