The grounding switch refers to a mechanical grounding device that releases the static electricity of the equipment and circuits to be repaired and to ensure the safety of the maintenance personnel during power outages. It can withstand the current for a certain period of time under abnormal conditions (such as a short circuit), but does not pass the load current under normal conditions. It is usually part of a disconnector.
(1) Normal working ground when servicing the line. When the circuit where the circuit breaker is located needs to be repaired, the circuit breaker is in the open position, and the isolation switches on both sides are open and in the open state. The grounding switch is closed for normal working grounding. To ensure the safety of equipment and maintenance personnel.
(2) It is compatible with static and electromagnetic induction current. In two or more common towers or overhead transmission lines arranged in parallel adjacent to each other, when one or more lines are out of power, due to electromagnetic and electrostatic induction between it and adjacent live lines, the circuit will Generates induced voltage and induced current. Therefore it is used for the grounding switch of this kind of line.
(3) Close the short-circuit current. For a grounding switch with a rated short-circuit closing current, it shall be able to close at any applied voltage including its rated voltage, and any current including its rated short-circuit closing current. The earthing switch has a rated short-circuit closing current equal to the rated peak withstand current.