1. Isolate the power supply to ensure safety
The main purpose of the isolating switch is to ensure the safety of the work during the maintenance of the device. Between the parts that need to be overhauled and other live parts, an isolating switch is used to form a sufficiently large and visible air insulation interval. The fracture of the isolating switch can not produce spark discharge in any state, so its fracture withstand voltage is generally 10% to 15% higher than the withstand voltage of its ground insulation. If necessary, a grounding switch should be attached to the isolating switch for grounding during maintenance.
2. Switching operation
That is, the isolation switch is used to switch electrical equipment or lines from one set of bus bars to another set of bus bars.
Operation sequence between circuit breaker and isolating switch
Ensure that the isolating switch "makes first and then breaks" (in the equipotential state, the isolating switch can also be operated independently). The operation sequence between the circuit breaker and the isolating switch must be strictly observed. ), otherwise it will cause misoperation, arcing and serious consequences.