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Question

Which component in an MCB is responsible for detecting a short circuit?

This question was previously asked in
RRB NTPC 2024 Undergraduate CBT 1 Question Paper (29-Aug-2025) (Shift 1)
The correct answer is

Solenoid

In the context of Miniature Circuit Breakers (MCBs), the component responsible for detecting a short circuit is the Solenoid. When a short circuit occurs, it creates an immediate and significant increase in electrical current. The solenoid, which is part of the electromagnetic mechanism in an MCB, detects this surge. The intense magnetic field generated by the excessive current activates the solenoid, causing a quick mechanical movement that trips the breaker and interrupts the circuit. This rapid response protects the electrical system by preventing potential damage caused by the extreme current associated with a short circuit.

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Similar Questions

  1. L series MCBs can be used effectively in:

  2. Fusing factor of fuse is always

  3. A shunt release in an MCCB is commonly used for:
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  5. What is used as a Circuit breaker?
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Important Questions from Circuit Breakers

  1. L series MCBs can be used effectively in:

  2. Fusing factor of fuse is always

  3. What is one of the functions of circuit breakers in a substation?

  4. For below 400 KV systems, the circuit breaker is designed to withstand ______above the normal system voltage.
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