What is the circuit breaker? All Questions › Category: Switchgear And Protection › What is the circuit breaker? 0 Vote Up Vote Down Chetan Shidling Staff asked 4 years ago I need short information. 1 Answers 0 Vote Up Vote Down Chetan Shidling Staff answered 4 years ago A circuit breaker is a device that is used in substation, industry, house, etc the purpose of the circuit breaker is to break the circuit when overload and a short circuit occur.