While electricity has become an indispensable component of our lives, the fact is, it comes with its own hazards to human life and property. Electrocution and fire being the two major risks associated with electricity, one cannot afford to be negligent when it comes to insulating equipment.
A circuit breaker is an electrical safety device designed to protect an electrical circuit from damage caused by overcurrent. Its basic function is to interrupt current flow to protect equipment and to prevent the risk of fire. Unlike a fuse, which operates once and then must be replaced, once dropped a circuit breaker can be reset (either manually or automatically) to resume normal operation.
Circuit breakers are made in varying sizes, from small devices that protect low-current circuits or individual household (domestic) appliances, to large switchgear designed to protect high voltage circuits (industrial) feeding an entire city. The generic function of a circuit breaker, or fuse, as an automatic means of removing power from a faulty system, is often abbreviated as OCPD (Over Current Protection Device).
Circuit breakers are varying from domestic to industrial and single phase to 3 phase power supplies.
Molded Case Circuit Breakers (MCCB)
MCCB is an electrical protection device which is used when load current exceeds the limit of a miniature circuit breaker.
The MCCB provides protection against overload, short circuit faults and is also used for switching the circuits.
Residual Current Circuit Breakers (RCCB)
A Residual Current Circuit Breaker (RCCB) is an important safety measure when it comes to protection of electrical circuits. It is a current sensing device, which can automatically measure and disconnect the circuit whenever a fault occurs in the connected circuit or the current exceeds the rated sensitivity.
Aimed at protecting an individual from the risk of electric shocks as well as electrocution and fires, RCCB is particularly helpful in instances of sudden earth fault. The presence of RCCB ensures that in such cases, the circuit will trip immediately and the person is thus protected from an electric shock.
Miniature Circuit Breakers (MCB)
MCB automatically switches OFF electrical circuit during any abnormal condition in the electrical network such as overload & short circuit conditions. However, fuse may sense these conditions but it has to be replaced; though MCB can be reset.
6kA is for domestic and 10kA for industrial usag
Isolator (Iso)
Generally used as a main switch or incomer inside a distribution board, an isolator does not offer any protection (not an automatic sensing device). It is used to completely disconnect the circuit from the electrical supply in order to achieve absolute isolation.
