MotorsQuestion 347 of 1506

A 480 V motor is designed to handle 10% voltage variation. What is the lowest voltage it should tolerate?

408 V
432 V
456 V
470 V

Show answer

Correct answer: 432 V

10% of 480 V is 48 V. 480 − 48 = 432 V.

Source: Troubleshooting Motors and Controls (Dickson-Self), 6.1: Testing Motor Components

Questions last reviewed: 18 October 2026

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