Question 190Electricity & Electronics - Assistant Engineer

70% to pass

Fuses are sometimes placed in series with a thermal trip-type circuit breaker. What is the purpose of a fuse used in this arrangement?

Ashort-circuit protection
Bshort duration surge protection
Ctime-delay protection
Dsustained overload protection
AI Explanation

The correct answer is A) short-circuit protection. The purpose of a fuse used in series with a thermal trip-type circuit breaker is to provide additional short-circuit protection. In this arrangement, the fuse acts as a backup to the circuit breaker, quickly interrupting high-current fault conditions that could potentially damage the circuit or equipment. The fuse is designed to melt and open the circuit when the current exceeds a certain level, while the circuit breaker provides protection against sustained overloads. This redundancy helps ensure the safety and reliability of the electrical system. The other options are incorrect because: B) the fuse does not provide short-duration surge protection, C) the fuse does not provide time-delay protection, and D) the circuit breaker, not the fuse, is responsible for sustained overload protection in this arrangement.

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