Question 65Electricity & Electronics - 1st Asst/Chief

70% to pass

A fuse is the most common type of protection against a short-circuit fault in LV distribution circuits, motor circuits and for portable appliances. What is a major drawback or deficiency with the use of fuse?

AIt is insensitive to small over current.
BIt has a very slow-speed of operation at high short-circuit fault current.
CIt generates a lot of heat when activated.
DIt does not provide protection in case of a short circuit.
AI Explanation

The correct answer is A) It is insensitive to small over current. The main drawback or deficiency with the use of fuses is that they are insensitive to small overcurrent conditions. Fuses are designed to protect against high-level short-circuit faults, but they may not reliably trip for smaller overload conditions that can still damage equipment over time. This makes fuses less suitable for providing comprehensive overcurrent protection, as they may not respond quickly enough to prevent damage from lower-level overloads. The other options are incorrect because fuses do provide protection against short-circuit faults, operate quickly at high fault currents, and do generate heat when activated, which is a normal part of their operation.

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