Question

Choose the correct option. (This question has multiple correct answers)
A. MCB is much more sensitive to over current than fuse
B. Fuse is much more sensitive to over current than MCB
C. Handling MCB is more electrically safe than fuse
D. Handling fuse is more electrically safe than MCB

Answer 1

Hint:Recall the basic information about the miniature circuit breaker (MCB) and the fuse. Explain the reaction and reaction time of reaction of the miniature circuit breaker (MCB) and fuse to over current in the circuit. Also, we should check which of the electric appliances wither MCB or fuse is safer to handle.

Complete answer:
Miniature circuit breaker (MCB) and fuse both are used in the low electrical voltage network.When the electric current in the circuit becomes over than the required normal value of the current, the miniature circuit breaker quickly detects this overcurrent and automatically the MCB turns off.But in case of a fuse, the over current in the circuit is not detected quickly and this may lead to damage the whole circuit.Thus, MCB is much more sensitive to over current than fuse.Hence, the option A is correct and option B is incorrect.

When the MCB turns off due to some fault in the circuit, the only position in the circuit where the fault is, trips off. So the faulty position in the MCB can be identified easily and repaired. This makes working with MCB safer.But in the case of a fuse, the faulty position in a fuse cannot be identified easily and to detect the fault in the circuit, one has to completely open the fuse and check about the fault. This may lead to some accidents. Hence, the handling fuse is not so safe.Thus, handling MCB is much safer than fuse.Hence, option C is correct and option D is incorrect.

Hence, option A and C are the correct answer.

Note: One can also explain that the MCB is safer to handle than fuse by another method. In a MCB, there are knobs or buttons used to switch on or switch off the circuit. But in case of a fuse, we need to open the whole circuit and do the needful things whenever required. This makes the handling of MCB safer than fuse.