Isolating switch (disconnect switch) is a kind of switch equipment without arc extinguishing device. It is mainly used to disconnect the circuit with no load current and isolate the power supply. There is an obvious disconnecting point in the open state to ensure the safe inspection and repair of other electrical equipment. It can reliably pass the normal load current and short-circuit fault current in the closed state.
Because it has no special arc extinguishing device, it cannot cut off the load current and short-circuit current. Therefore, the isolating switch can only be operated when the circuit has been disconnected by the circuit breaker. It is strictly forbidden to operate with load to avoid serious equipment and personal accidents. Only voltage transformers, lightning arresters, no-load transformers with excitation current less than 2A, and no-load circuits with current less than 5A can be directly operated with isolation switches.
Load bvreak switch (LBS) is a kind of switching device between the circuit breaker and the isolating switch. It has a simple arc extinguishing device, which can cut off the rated load current and a certain overload current, but cannot cut off the short-circuit current.
The difference:
Different from the isolating switch, the load switch has an arc extinguishing device, which can automatically trip the load switch through the thermal release when overloaded.
Post time: Nov-30-2021