The primary function for a Miniature Circuit Breaker (MCB) is to first detect a fault condition, this is usually done within the device itself.
Once a fault is detected, the copper (or other highly conductive material) contacts within the MCB open in order to interrupt the circuit, this is generally done by using mechanically stored energy contained within the breaker.
The circuit breaker contacts carry the load current without excessive heating and must also withstand the heat of the arc produced when interrupting (opening) the circuit.
Service life of the MCB contacts is generally affected by the erosion of contact material due to arcing while interrupting the current. Once contacts are worn, it is best practice to discard and replace the circuit breakers.
We have a wide range of miniature circuit breakers available which can be viewed and purchased online. We also offer the opportunity to download a pdf datasheet for each product type.