Maintenance and Upkeep of Low-Voltage Switchgear

The core of low-voltage switchgear maintenance and upkeep is regular inspection, cleaning and dust removal, tightening connections, and testing insulation and functionality to ensure safe and stable equipment operation. Proper maintenance can effectively prevent malfunctions, extend equipment lifespan, and ensure continuous power supply.

 

Daily Maintenance (Daily/Weekly Inspection Recommended)

Appearance and Environmental Inspection

Inspect the cabinet for deformation, corrosion, or coating peeling. Ensure the door seals are intact to prevent dust and moisture intrusion.

Ensure the operating environment temperature is ≤40℃, humidity ≤90% with no condensation, good ventilation, and no risk of water leakage or small animal intrusion.

Listen for any abnormal sounds inside the cabinet (such as discharge sounds or vibration sounds), and observe whether the instruments and indicator lights are functioning normally.

Cleaning and Dust Removal

Use a dry, soft cloth or vacuum cleaner to remove dust from the inside and outside of the cabinet, paying particular attention to cleaning the ventilation holes, busbars, and insulator surfaces.

Avoid using corrosive cleaning agents to prevent damage to electrical components.

Labeling and Tool Check

Check that warning signs, maintenance signs, and operating button labels are clear and correctly positioned.

Confirm that emergency tools, lights, crank handles, fuse handles, etc., are complete and usable

 

Regular Maintenance (Recommended every 3-6 months)

Electrical Connection Tightening

Check that the bolts connecting busbars, cable joints, terminal blocks, etc., are loose. Tighten them to the standard torque using a torque wrench.

Observe the contact points for overheating or discoloration (silver-white is normal; blackening or discoloration requires treatment).

Insulation Performance Testing

After power is off, use a megohmmeter to measure the phase-to-phase and phase-to-ground insulation resistance. It should be ≥1MΩ.

Check the insulation material for cracks, aging, or discharge marks.

 

Functional Component Inspection

Circuit Breaker: Manually open and close the circuit breaker 3 times to check its mechanical performance for flexibility and the integrity of the arc-extinguishing chamber.

Contactor/Relay: Check the contacts for oxidation or ablation; the coil temperature should not exceed 65℃.

Capacitor cabinet: After disconnecting the main switch, discharge each capacitor one by one, checking for bulging, leakage, and reliable grounding.

Fan and cooling system

Check if the cabinet fan is operating normally and if the vents are blocked. Clean or replace the filter if necessary.