Question

In a household electric circuit, where MCB (miniature circuit breaker) connected?

Answer 1

Hint : MCB is connected to the main fuse board. MCB is created to safeguard from defects in excessive current and overheating. When the current crosses the defined unit, MCB automatically switches off and the loop breaks.The MCB is much more reliable in the detection of such conditions, it is more sensitive to change in current.

Complete step by step answer
A miniature circuit breaker is an electromagnetic device that carries a complete molded insulating material. The primary function of this switch is to switch the circuit, This means to automatically open the circuit when the current passing through the circuit goes beyond a set value or limit. The device can be manually switched ON or OFF just like a normal switch when necessary.
MCB (miniature circuit breaker):
-It works on switching principle and electromagnetic.
-It is used for low energy requirements such as small electronic circuit or home wiring.
There are two arrangements for operation of miniature circuit breakers. One due to thermal effect of over current and other due to electromagnetic magnetic effect of over current. The thermal operation of the miniature circuit breaker is achieved with a bimetallic strip whenever continuous current flows through MCB, the bimetallic strip is heated and deflected by bending. The deflection of the bimetallic strip releases a mechanical latch and this latch is attached to the operating mechanism, It causes the miniature circuit breaker contacts to open.

Note
-Up to 100 amperes of MCB are used in motor feeders.
-MCB can be reused and thus it is cheaper than fuse.
-MCB is more sensitive to current.
-The handling of an MCB is more electrically safe than a fuse.
-The only one disadvantage of MCB over fuse is that this system is costlier than a fuse unit system.