What Does B20 Mean On A Circuit Breaker?

On a circuit breaker, the letter “B20” provides detailed information about the type and rating of the circuit breaker:

Type B Circuit Breaker

The tripping characteristic of the circuit breaker is referred to as Type B type of breaker.

Breakers of type B are designed to trip at a current that is between three and five times the full load current.

In conditions where there is a low probability of large inrush currents, they are often utilized for the purpose of protecting electrical circuits in residential or light business settings.

Because of this, they are suited for applications that require general-purpose functionality, such as lighting & socket outlet circuits.

Term “20”

20 is the current rating of the breaker, expressed in amperes, and this number reflects that rating.

The number “20” indicates that the circuit breaker is capable of withstanding a continuous current of up to 20 amps without tripping.

In case that the current is more than this value, the circuit breaker will trip in order to prevent the circuit from overheating & subsequent faults.

Thus, the Type B circuit breaker that has a current rating of 20 amps is referred to as a B20 circuit breaker.

The circuits that require a moderate level of protection, which are typically found in residential settings, are suited for its application.