Advantages and disadvantages of MCBs over fuses?

Answer 1

Fuses and minature circuit breakers (MCBs) are both overcurrent protection devices, designed to disconnect a circuit in the event of an overload current or a short-circuit current.

Fuses use the heating effect of current in order to operate. When an overcurrent occurs, the temperature of the fuse element causes it to melt, disconnecting the circuit. Its speed of operation is based on the inverse-time characteristic of the melting process -i.e. the higher the overcurrent, the faster it melts.

Miniature circuit breakers use the heating effect, together with the magnetic effect, of current to operate. Overload currents cause a bimetallic strip to bend, releasing the trip mechanism. Short-circuit currents cause an electromagnet to release the trip mechanism. The inverse-time characteristics of these two processes overlap.

MCBs have the advantage that they do not have to be replaced, once the fault has been removed from the circuit, and can be reset to their closed position. Fuses must be replaced. Fuses are also subject to abuse, as people sometimes replace 'blown' fuses with fuses of the wrong rating, or even replace them with strips of tinfoil or nails which completely removes any circuit protection.

Answer 2

Advantages of MCBs over fuses include faster response time, ability to be easily reset, and better protection against overloads and short circuits. However, MCBs are more expensive upfront, and their components can wear out over time, leading to potential failures. Fuses, on the other hand, are generally more cost-effective and simpler in construction, but they need to be replaced after each trip.

Answer 3

MCbs don't have a melting wire.. which means that they don't have to be replaced every time they cut off.. hence.. mcbs are better than traditional fuse wires..