Maintenance of High-Voltage Distribution Box and Switchgear

Many factories or construction sites have distribution boxes and cabinets that experience various faults. At such times, we need to inspect and repair the distribution cabinets to ensure safe electricity use and prevent major accidents. So, as an electrician, how should you proceed with inspecting the electrical circuits of a distribution cabinet?

First, the inspection of electrical circuits in low-voltage distribution cabinets should be performed by electricians. Non-electricians might mishandle operations, causing damage to electrical components. Moreover, at least two people are required during the inspection process. One person should guard the main switch distribution box to prevent others from turning the circuit back on after it has been disconnected, ensuring the safety of the electrician performing the inspection. The electrician inspecting the circuit should only proceed after confirming that the main switch is off and using tools like a test pen or multimeter to ensure that the electrical components are not live.

The tasks for inspecting electrical circuits are as follows:

1. Regularly check the motor for vibrations or abnormal noises, and promptly replace bearings or add lubricating oil.

2. Periodically tighten the bolts at electrical connection points, such as contactors, transformers, and motors.

3. Check whether the motor current is normal.

4. Inspect the extent of damage to the contacts of components like contactors and relays, and address any issues.

5. Check whether the motor protective cover is secure and intact.

6. Inspect the operation of the exhaust and cooling systems in each distribution cabinet and address any issues.

7. Regularly check the phase-to-phase insulation and ground insulation of the motor.

8. Inspect the cooling system of the transformer to ensure it is well-ventilated.

9. Frequently check whether the external temperature of the motor is normal.