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Dongli Electric

Safety Measures and Protective Grounding of High and Low Voltage Switchgear


Release time:

2020-08-28

High and low voltage switchgear is a kind of electrical equipment. The external line enters the main control switch in the cabinet and then enters the sub-control switch. Each branch is set according to its needs, such as instrument, automatic control, motor magnetic switch, various AC contactors, etc. Some are also equipped with high voltage chamber and low voltage chamber switch cabinets, with high voltage busbars, such as power plants, etc. Some are also equipped with low-cycle load reduction to protect the main equipment.

High and low voltage switchgearWork shall be carried out on fully and partially live panels, the maintenance equipment shall be separated from the operating equipment with obvious signs, and the secondary winding with current transformer and voltage transformer shall have a reliable and reliable protective grounding.

High and low voltage switchgearWhen working on the secondary circuit of a running current transformer. The following safety measures shall be taken:

1. It is forbidden to disconnect the current circuit.

2. In order to reliably short-circuit the secondary coil of the current transformer. Short-circuit pieces and short-circuit lines must be used, and wire winding is prohibited.

3. It is forbidden to do any work on the circuit and wire between the current transformer and the short-circuit terminal.

4. When working on the secondary circuit of the voltage transformer in operation.

High and low voltage switchgearTake the following safety measures:

1. Strictly prevent short circuit or grounding.

2. Insulated tools and insulating gloves should be used. If necessary, stop the relevant relay protection devices before work.

3. When receiving temporary load. Must be equipped with special switches and fuses.

4. During the secondary circuit power-on test, in order to prevent the primary reverse voltage from the secondary side, in addition to disconnecting the secondary circuit, the primary fuse should also be removed.

5. Before the secondary circuit is electrified or withstand voltage test, the attendant and relevant personnel shall be notified. And send people to guard the site, check the circuit, and confirm that no one is working before pressurizing.

6. Check the staff of power-off protection and secondary circuit. No switching operation is allowed without the permission of the personnel on duty.

High and low voltage switchgearIt is a kind of electrical equipment. The external line enters the main control switch in the cabinet and then enters the sub-control switch. Each branch is set according to its needs, such as instrument, automatic control, motor magnetic switch, various AC contactors, etc. Some are also equipped with high-voltage chamber and low-voltage chamber switch cabinets, with high-voltage bus bars, such as power plants, etc., and some are also equipped with low-cycle load shedding to ensure for main equipment.