Maintenance content and steps of low-voltage distribution cabinet

1: The maintenance should start from the low-voltage side of the transformer. After powering off the power distribution cabinet, clean the dust in the cabinet, check whether the bus and down lead connections are good, whether there is heat or discoloration at the joint points, check whether the cable head and connection pile head are firm and reliable, check whether the ground wire is rusted, and whether the connection pile head is fastened. All secondary circuit wiring connections are reliable, and the insulation meets the requirements.

When checking the drawer type switch, the drawer type switch cabinet should be flexible when being pushed in or pulled out, and the mechanical locking should be reliable. Check whether the automatic air switch operating mechanism on the drawer cabinet is in place and whether the wiring screws are tight. Clean the dirt on and around the contact surface of the contactor, and check whether the contact is in good condition. If the contact is in poor contact, slightly file the contact surface if necessary. If the contact is severely ablated (the contact point is worn to 1/3 of the original thickness), replace the contact. The power indicator and indicator light are intact.

When repairing the capacitor cabinet, first disconnect the main switch of the capacitor cabinet, discharge the capacitors one by one to the ground with a wire of more than 10mm2, and inspect the appearance to ensure that the housing is in good condition without oil leakage. If the capacitor housing expands, it should be handled in a timely manner. Replace the discharge device, the wiring screws of the control circuit, and the grounding device. After closing, debug the indication part and automatic compensation part.

4. Maintenance of circuit breakers in the power receiving cabinet and contact cabinet: first disconnect all loads, and then use the handle to shake out the circuit breaker. Retighten the wiring screws and check whether the elastic force of the blade meets the requirements. Check whether the arc extinguishing grid is cracked or damaged, manually adjust whether the mechanical interlocking opening and closing is accurate, check whether the contact is in good contact, file the contact surface if necessary, and check whether the internal springs, gaskets, and screws are loose, deformed, and falling off.