What the difference between circuit breakers and isolator?

An **isolator** and a **circuit breaker** are two different types of electrical switches used in power systems.

The major difference between the two is that an isolator is an off-load device, while a circuit breaker is an on-load device ¹.

An **isolator** is used to disconnect a part of the circuit from the main supply for maintenance purposes. It is an off-load device that operates under no current conditions ¹².

An isolator is a mechanical switch that can be operated manually ¹. It is used in high voltage devices such as transformers, etc. Isolators block the DC signals and allow the AC signals to pass ¹.

A **circuit breaker**, on the other hand, is a protection device that trips the entire system if there is any fault. It is an on-load device that operates under current conditions ¹².

A circuit breaker is an electronic device made by using MOSFET or BJT ¹. It opens and closes the contact of the circuit at normal as well as when faulty conditions occur in the system.

It automatically disconnects the circuit when an overload current or short circuit takes place ¹².