There are 7 typical risks associated with switchgear wiring.
1. In the voltage transformer cabinet, the lightning arrester is directly connected to the busbar;
2. There is a live busbar connected from adjacent cabinets at the bottom of the busbar switchgear;
3. The switchgear adopts a dual busbar connection method, which can introduce the operating busbar voltage into the maintenance room;
4. The lower part of the switchgear is not completely isolated from the rear, and maintenance personnel can access the rear live equipment;
5. The upper part of the switchgear is not tightly sealed, and the live busbar can be seen;
6. The switchgear belongs to the main transformer incoming cabinet, with live contacts or the ability to make phone calls at any time;
7. The switchgear belongs to the contact cabinet, and the contacts can be electrified or make phone calls at any time.
Three isolation measures should be taken during maintenance.
When charging the static contact of the switch, the static contact hole must be closed with an isolation baffle. If there are no signs of stop or high voltage danger on the isolation baffle, an insulation bracket should be added in front of the isolation baffle and a stop or high voltage danger sign should be hung. It is strictly prohibited to open the isolation barrier during work, and any part of the body is strictly prohibited from passing through the isolation barrier.
2. If there is no grounded cable in the outgoing (or incoming) cable compartment, the cable compartment must be reliably locked and hung with stop and high-voltage danger signs.
3. In the switchgear, if the busbar is exposed above the maintenance work area and does not meet the safety distance requirements, a partition must be installed.
Two should:
1. The interconnection line switchgear should be equipped with a live display and a live locking device.
2. Clear warning signs should be set up at the entrance doors of the switch cabinets of lines that may be called for, such as interconnection lines and main transformer incoming lines.
Two mustaches:
1. It is necessary to accurately grasp the internal structure and electrical wiring methods of the switchgear, clarify the main danger points in work, and notify all class members.
2. In the maintenance state of the switchgear, the maintenance compartment must be completely isolated from the electric compartment.
Three mustn't:
1. After the work permit is granted, maintenance personnel are not allowed to open unauthorized enclosed compartments on their own.
2. The handcart switch in the maintenance position must be pulled outside the cabinet, and the test position or middle position must not work.
3. The interlocking inside the switchgear shall not be forcibly released, and the key shall not be unlocked arbitrarily.
Three Stricts:
1. Strictly implement the operation ticket system.
2. Strictly implement the operation monitoring system.
3. Strictly check the equipment status and displacement, and confirm that the operating object is correct and the equipment status is accurate.