Low-voltage distribution facilities live maintenance precautions

In order not to affect the normal power supply, it is sometimes necessary to perform low-voltage electrification maintenance on low-voltage equipment such as low-voltage distribution cabinets. The general low-voltage electrification maintenance should pay attention to the following matters.

1. There should be special guardianship. The purpose is that if an accident occurs during maintenance, the guardian can immediately cut off the power supply (disconnect the circuit breaker or knife switch in the power distribution cabinet, or unplug the fuse); in addition, when the repairer may touch or excessive When approaching the conductor or mishandling, the guardian can promptly remind you to prevent electric shock and other accidents.

2. Tools with insulated handles should be used. When working, stand on dry insulation (such as wooden ladders, wooden tables, stools, etc.), wear gloves (such as dry cloth gloves), and wear insulated shoes (such as rubber shoes, Plastic bottom shoes). If you are working on the line, you should also bring a helmet. Must work in long sleeves. Tools such as trowels, steel tape measures and metal brushes, piercing screwdrivers and ordinary wire cutters are strictly prohibited.

3. When overhauling the low-voltage strips on the high-voltage and low-voltage poles or overhauling the transformers, check the distance from the high-voltage live parts and take measures to prevent accidental contact with high-voltage live parts. The maintenance personnel shall not traverse when the low-voltage live conductor is not insulated. When acting on power distribution units such as live low-voltage distribution cabinets, isolation measures should be taken to prevent phase-to-phase short-circuit and single-phase grounding.  

4. Before climbing the pole, transformer station or equipment, the phase line, neutral line and ground line should be separated first, and the working position should be selected. When disconnecting the wire, disconnect the phase wire first, then disconnect the neutral wire or ground wire; when the wires are lapped, the order is reversed. The human body must not touch two thread ends at the same time.

5. When overhauling the live watt-hour meter and relay circuit in the power distribution cabinet, the secondary windings of the voltage transformer and current transformer should be reliably grounded. When disconnecting the current loop, short-circuit the dedicated terminal on the secondary side of the current transformer.

6. Standing ladders and stools should be placed firmly, and some people should be supported below to prevent the maintenance personnel from slipping down.

7. When repairing the phase line and the neutral line (the phase line of two different phases), the wiring pile head, such as the power switch, the terminal block of the power distribution cabinet, the relay, the transfer switch, etc., should be carried out with great care (generally Should be shut down for maintenance, eyes should not be close, otherwise it is easy to cause short-circuit accidents and burn your eyes.

8. Charged maintenance should pay attention to the ground moisture-proof and waterproof; outdoor live maintenance should be avoided on rainy days. Thunderstorm days should stop the elective maintenance work.

After the live maintenance is over, you should check it carefully. The inspection content is the same as the power failure maintenance.