Which device resets after a fault and does not require replacement?

Which device resets after a fault and does not require replacement?

• A. Fuse
• B. Circuit breaker
• C. Both fuse and circuit breaker
• D. Neither

Answer: (B)

The concept here is understanding which protective device can be reset after tripping. A circuit breaker is designed to interrupt current during an overload or short circuit and then be reset once the fault is cleared. After tripping, you simply reset it by flipping the switch or pressing a reset button, making it reusable without replacement. A fuse, on the other hand, contains a metal element that melts when excessive current flows. Once melted, the fuse is blown and must be replaced; it cannot be reset. So, the device that resets after a fault and does not require replacement is the circuit breaker.

The concept here is understanding which protective device can be reset after tripping. A circuit breaker is designed to interrupt current during an overload or short circuit and then be reset once the fault is cleared. After tripping, you simply reset it by flipping the switch or pressing a reset button, making it reusable without replacement.

A fuse, on the other hand, contains a metal element that melts when excessive current flows. Once melted, the fuse is blown and must be replaced; it cannot be reset.

So, the device that resets after a fault and does not require replacement is the circuit breaker.