Meters and troubleshootingQuestion 1122 of 1506

What is the standard secondary voltage of a potential transformer (PT) at full rated line voltage?

5 V AC
120 V AC
24 V AC
600 V AC

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Correct answer: 120 V AC

PTs step the line voltage down to 120 V AC for a standard 150 V full-scale voltmeter.

Source: Lessons in Electric Circuits II: AC (Kuphaldt), 10.7: Special Transformers and Applications

Questions last reviewed: 18 October 2026

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