MCB (Miniature Circuit Board) is a safety device with significant applications in both commercial and residential areas. This device is an electro-mechanical circuit protection device. Through an automatic safety mechanism, it prevents electrical circuits from being damaged by excessive current flow.
The MCB operates automatically, which means that if a short circuit or overcurrent occurs, the MCB will trip, interrupting the power supply and preventing any damages from occurring. Despite this, these devices are sensitive to even the smallest variations in current and can detect minute levels above the safety limit. An MCB interrupts a circuit when it is overloaded or shorted.

An MCB can be used as a substitute for a fuse in household applications. Over-fuses for MCBs have the advantage of being reusable even after an overload, or short circuit interrupts the circuit.

A Miniature Circuit Breaker (MCB) is a device that uses an electromagnetic device encased in a molded insulation enclosure. Its primary function is to switch the circuit, which means that it opens the circuit (connected to it) if the current passing through it (MCB) exceeds its setting. Like a normal switch, it can be manually turned on and off.