This article deals with the differences between isolators and circuit breakers.
In a power system, an isolator is used to de-energize the electrical circuit connected to it. An isolator completely isolates the state of a system. It is commonly used in several electrical and industrial applications. Also, they are manually operated devices.
Circuit breaker is a protection device used in electrical power system. It can prevent the systems from damages caused by overload and short circuit conditions. It has become an essential protection device in residential buildings and all other industries.
Differences between isolators and circuit breakers
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| Fig 1. Isolator and Circuit breaker |
In a power system, an isolator is used to de-energize the electrical circuit connected to it. An isolator completely isolates the state of a system. It is commonly used in several electrical and industrial applications. Also, they are manually operated devices.
Circuit breaker is a protection device used in electrical power system. It can prevent the systems from damages caused by overload and short circuit conditions. It has become an essential protection device in residential buildings and all other industries.
Differences between isolators and circuit breakers
- Isolators are manually operated switches while circuit breakers are automatically operated ones. Isolator disconnects the circuit from its live nature through manual operation. While circuit breaker protects the system and its electrical connections from overcurrents and short circuits through its automatic triggering operation.
- Advanced circuit breakers extinguish the electric arc generated between the contacts after its tripping. But isolators fail to do so. Due to this reason, isolators are intended to operate only after the current has been interrupted by the circuit breakers or any other control devices. That is why isolators are called off-load devices and circuit breakers are referred to as on-load devices.
- Isolators are manually operated after the circuit breaker gets tripped. It can provide clearance of several meters. After fault clearance, the isolator is first closed and then the CB is closed thus restoring a live connection.
