A grounding autotransformer is used to create a three-phase, 3-wire ungrounded system. What characteristic does this system have regarding grounding?

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Multiple Choice

A grounding autotransformer is used to create a three-phase, 3-wire ungrounded system. What characteristic does this system have regarding grounding?

Explanation:
The system is designed to float with respect to earth, meaning there is no intentional connection from any conductor to ground. A grounding autotransformer is used to create the neutral point for grounding when needed, but in this setup that neutral is not connected to earth, so the three-phase, 3-wire system remains ungrounded by design. In practical terms, there isn’t a solid path to earth for fault currents, and voltages to ground on the phases can become unbalanced after a fault. This is why the characteristic described is that it is not intentionally grounded.

The system is designed to float with respect to earth, meaning there is no intentional connection from any conductor to ground. A grounding autotransformer is used to create the neutral point for grounding when needed, but in this setup that neutral is not connected to earth, so the three-phase, 3-wire system remains ungrounded by design.

In practical terms, there isn’t a solid path to earth for fault currents, and voltages to ground on the phases can become unbalanced after a fault. This is why the characteristic described is that it is not intentionally grounded.

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