A substation has a 600V, 3-phase feeder with a total load of 1200A. What is the minimum conductor size required for this feeder?

Texas Master exam practice question · Branch Circuit Conductors

A substation has a 600V, 3-phase feeder with a total load of 1200A. What is the minimum conductor size required for this feeder?

A250 kcmil
B300 kcmil
350 kcmil
D400 kcmil

Exam tip

When dealing with feeders, it is important to refer to specific tables in the NEC to determine the correct conductor size.

Why C is correct

According to 2026 NEC Article 310.15(B)(16), the minimum conductor size for a 600V, 3-phase feeder with a 1200A load is 350 kcmil. Larger conductors are not required for this application.

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A substation has a 600V, 3-phase feeder with a total load of 1200A. What is the minimum conductor size required for this feeder?

A substation has a 600V, 3-phase feeder with a total load of 1200A. What is the minimum conductor size required for this feeder?

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