Circuit breaker
Türkçe: Kesici
A switching device that can make and break normal load current and short-circuit current, opening the circuit on command from a protection relay during a fault.
// EXPLANATION
Unlike a disconnector, a breaker can interrupt load and fault current, so in a switching sequence the breaker opens first and the disconnector afterwards. In MV there are vacuum, SF6 and oil types, named after the arc-quenching medium. In LV a miniature circuit breaker does the same job.
// ALSO KNOWN AS
breakercircuit breakercircuit-breaker
// RELATED TERMS
DisconnectorA safety switch that opens a de-energised circuit to create a visible air gap; it has no capability to interrupt current.
Protection relayA device that measures quantities such as current and voltage and sends a trip command to the breaker when it detects a fault.
Short circuitA condition where live conductors join through a very low-impedance path, so hundreds of times the normal current flows.
SF6 gasA gas used in MV/HV switchgear for its excellent insulation and arc-quenching properties, and also a very potent greenhouse gas.
