What is a circuit switcher?

Answer 1

Circuit Switching

Circuit switching is used for ordinary non-digital telephone systems. It allows communications equipment and circuits to be shared among users. Each user has sole access to a circuit (functionally equivalent to a pair of copper wires) during network use.

A circuit switching network is the one that establishes a dedicated circuit or channel between nodes and terminals before the user may communicate. Each circuit that is dedicated cannot be used by other callers until the circuit is released and a new connection is set up. Even if no actual communication is taking place in a dedicated circuit's channel, that channel still remains unavailable to other users. Any other channel that is available remains unconnected (set to "idle") until a new call appears.

Answer 2

A mechanical switching device with an integral interrupter, suitable for making, carrying, and interrupting currents under normal circuit conditions. It is also suitable for interrupting specified primary-bus fault current and transformer-limited fault current that may be less than its rated short circuit making current and rated short-time withstand current.

This definition comes from IEEE Standard C37.016 titled "IEEE Standard for AC High-Voltage Circuit Switchers rated 15.5 kV through 245 kV."

Additional ratings for line-charging switching current, cable charging switching current, shunt capacitor bank switching current, and peak capacitive inrush current may also be available from the device manufacturer.