Question 8010 of 749 · Maryland Journeyperson Electrician Exam
How many overload units are required for a three-phase ac motor?
Exactly one answer is correct.
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Correct answer to question 8010
- B: Three, one in each phase
Explanation
Table 430.37 requires three overload units for three-phase ac motors, one in each phase conductor. This protects the motor even if one phase is lost.
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