Full Form of MCB

Full Form of MCB:

Miniature Circuit Breaker

MCB Full Form is Miniature Circuit Breaker. Over current, on account of its extreme fluctuations, has the ability to cause permanent damage to cables, conductors, and electrical devices. Since one cannot control over current, there has to be protective measure in the electrical circuit which interrupts this over current (higher than rated current) at homes and industrial locations.

The miniature circuit breaker (MCB) is one such protective measure for the electrical circuits generally installed at the distribution boards locally. MCBs are electromechanical devices which function by cutting off the electrical flow through a circuit when a fault is detected. Whenever the current in the circuit exceeds the rated capacity of the circuit, the MCB switch automatically turns off.

Full Form of MCB
Full Form of MCB

There are 3 MCB types, Type B, Type C and Type D, and the speed at which a circuit trip depends on upon the level of overload. MCB consist of a bimetallic strip which is connected to a metallic deflector which is in touch with a mechanical latch. The bimetallic strip acts both as a thermal trip unit and magnetic trip unit.By keeping the MCBs at off position, the circuit opens up and no current flows through the circuit. During it’s on position, the MCB acts like a fuse or safety device. It functions in two ways:

Thermal Displacement: When continuous overcurrent flows through the metallic strip in the MCB, the heated strip deflects releasing the mechanical latch thereby causing the circuit to open.

Electromechanical Displacement: During periods of wide fluctuations in current and short-circuiting, the magnetic protection is the MCBs are activated. Fluctuating current causes strong magnetic field generation in this bimetallic strip which opens the metallic contact between the magnetic strip and the switch.