On functional, an isolator switch is used to disconnect the upstream current, but it can not operate on service . The isolator switch is essential for power distribution system, because it could provide an obvious seen disconnecting point to protect maintenance personnel from the danger of electric shock. Commonly, an isolator switch need to combine with circuit breaker and earthing switch to apply in the power distribution system.
On the function, an isolator switch is designed to provide a visible disconnecting point in power distribution system to protect maintenance personnel from the risk of electric shock. More over, an isolator switch does not have an arc extinguishing chamber to cut down upstream current as the simple design. However, a circuit breaker is designed to shut down electrical circuit to protect electrical equipment from short circuit and over load. That is to say, a circuit breaker has the arc extinguishing chamber. Because of the design, a circuit breaker can not supply a visible disconnecting point.
