Question 312Electricity/Electronics - Assistant Engineer70% to pass
As shown in figure "A" of the ungrounded distribution system with possible ground faults shown in the illustration, under what conditions would an outage likely occur due to a ground fault causing a circuit breaker to trip? Illustration EL-0129
AI Explanation
The correct answer is A) two ground faults associated with different phases.
In an ungrounded distribution system, a single ground fault will not cause a circuit breaker to trip since the system is not grounded. However, if there are two ground faults associated with different phases, it can create a low-impedance path between those phases, resulting in a phase-to-phase fault. This condition is likely to trigger the circuit breaker to trip, causing an outage.
The other options are incorrect because: B) a single ground fault will not cause an outage, C) ground faults can result in outages under certain conditions, and D) two ground faults on the same phase would not create a phase-to-phase fault.
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