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Question

What is used as a Circuit breaker?

This question was previously asked in
RRB ALP 2018 CBT 2 Fitter Question Paper (21-Jan-2019) (Shift 3)
The correct answer is
fuse

Circuit Breaker Function Explained

The question asks to identify a device used as a circuit breaker. A circuit breaker's primary function is to interrupt the flow of electrical current in a circuit when it becomes unsafe, typically due to an overload or short circuit.

Role of a Fuse

A fuse is specifically designed for this purpose. It contains a wire or filament that melts and breaks the circuit when the current exceeds a predetermined safe level. This protects the circuit and connected appliances from damage.

  • Fuse: Acts as a sacrificial device to break the circuit automatically upon overcurrent.

Why Other Options Are Less Suitable

Let's look at the other options:

  • Resistor: Resistors are used to impede or resist the flow of current but do not break the circuit.
  • Switch: A switch is used for manual control; it opens or closes a circuit by user action but does not automatically protect against overcurrents.
  • Resettable protective device: This is a broader category that includes modern circuit breakers (like MCBs). While fuses also protect circuits, the specific option 'fuse' directly represents a classic type of device used for this function and is often the intended answer in basic contexts. Given the options and the common understanding, the fuse is the most direct answer representing a device used *as* a circuit breaker.

Therefore, a fuse is commonly used as a simple and effective circuit breaker.

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Similar Questions

  1. L series MCBs can be used effectively in:

  2. Fusing factor of fuse is always

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

  4. A shunt release in an MCCB is commonly used for:
  5. A single device that ensures efficient protection from electrical hazard of shock and fire caused by over current, short circuit, earth leakage, and earth fault is:

  6. Which component in a wiring diagram is specifically used to protect against overcurrent?

  7. Which statement best describes an isolating switch?

  8. A domestic MCCB is marked 25A, 6 kA, 230V AC. Which fault current will this MCCB safely interrupt?

  9. If an ELCB in a domestic installation trips occasionally without any apparent fault, what could be a probable reason?

  10. An industrial panel uses a cartridge fuse rated at 250V, 32A. If a technician replaces it with a 16A fuse of the same voltage rating, what is the likely outcome during normal operation at 28A?


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.
  5. If Ic is the critical current and Zo is the surge impedance, the basic impulse insulation level can be calculated as

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