Question 131Electricity & Electronics - QMED

70% to pass

Which device will stop the motor shown in the illustration in case of a short-circuit (high current) motor fault? Illustration EL-0080

Diagram for USCG Electrical QMED: Which device will stop the motor shown in the illustration in case of a...
Atransformer primary fuses FU4 and FU5
Bdisconnect switch fuses FU1, FU2, and FU3
Ctransformer secondary fuses FU6 and FU7
Doverload relay heaters and overload relay NC contacts (OL)
AI Explanation

The correct answer is B) disconnect switch fuses FU1, FU2, and FU3. In the event of a short-circuit or high current fault in the motor circuit, the disconnect switch fuses FU1, FU2, and FU3 would be the first line of defense to stop the motor. These fuses are positioned before the motor and would quickly open to interrupt the flow of excessive current, protecting the motor from damage. The other options are not correct because: A) the transformer primary fuses FU4 and FU5 are not directly in the motor circuit, C) the transformer secondary fuses FU6 and FU7 would not be able to stop the motor, and D) the overload relay is designed to protect against prolonged overloads, not immediate short-circuit faults.

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