Safety measures for power failure of electrical equipment in Guizhou

1. Equipment that must be powered off at the workplace:

(1) live equipment with normal activity range less than safety distance (10kV safety distance is 0.35m).

(2) equipment with live parts behind or on both sides of the staff and without reliable safety measures.

2. The scope of power failure for line operation:

(1) repair the outgoing line problem and contact switch of the line.

(2) it is possible to return the power supply to all switches of the maintenance line.

3. Precautions for power failure:

(1) when the inspection equipment is cut off, all aspects of power supply must be disconnected, and at least one obvious disconnection point (such as isolating switch, knife switch, etc.) must be provided. It is forbidden to work on the equipment only passing through the circuit breaker or automatic switching power supply, and the isolating switch of the circuit must be disconnected.

(2) in order to prevent the possibility of reverse power supply, the transformer and voltage transformer related to the power cut equipment should be disconnected from both high and low voltage sides.

(3) the operating handle must be locked for the isolating switch which can be transmitted to the power cut equipment once it is closed.

Electrical safety measures

1. After the power failure of maintenance equipment, before connecting the ground wire, the electroscope must be used to check whether there is voltage.

2. The electroscope with appropriate voltage level and valid test period must be used for electricity test.

3. Before electricity test, the electroscope should be tested on the live equipment to see if it is in good condition.

4. It should be carried out separately at the inlet and outlet of construction or maintenance equipment.

5. Insulating gloves must be worn for high voltage test.

6. When the circuit breaker or switch used for connection is overhauled, the power shall be tested on both sides.

7. The power test of the line should be carried out phase by phase. For multi-layer power lines erected together, the lower layer shall be inspected first, and the upper layer shall be inspected later.

Installation of temporary ground wire for electrical equipment in Guizhou

1. During installation, the grounding end shall be reliably grounded first. When it is verified that the equipment or line has no voltage, the other end (conductor end) of the temporary grounding wire shall be connected to the conductive part of the equipment or line immediately. At this time, the equipment or line has been grounded and three-phase short circuit has occurred. On the contrary, remove the conductor end first.

2. Multiple strands of soft bare copper wire shall be used for temporary grounding wire, and the cross section shall not be less than 25mm2.

3. When the circuit breaker or disconnector of section bus is disconnected, each section shall be checked and grounded respectively before maintenance. If all the high and low voltage power transformation and distribution rooms need to be cut off, the switch of the high voltage incoming cabinet that may come in should be twisted to the grounding position.

4. Temporary grounding wire shall be installed in the place where the working point can be seen.

5. The equipment or cable line with capacitance shall be discharged before installing temporary grounding wire.

6. Installation and removal of temporary grounding wire must be carried out by two people. If one person is on duty, only grounding disconnector is allowed to be used for grounding.