A raceway is filled with 12 AWG copper conductors. What is the maximum allowable fill, according to the 2026 NEC?

Texas Master exam practice question · Wiring Methods & Materials

A raceway is filled with 12 AWG copper conductors. What is the maximum allowable fill, according to the 2026 NEC?

A60%
70%
C80%
D90%

Exam tip

Remember the conduit fill calculations apply to raceways as well.

Why B is correct

The 2026 NEC Article 318.10(A) allows for a maximum fill of 70% for conductors in raceways. The 60%, 80%, and 90% options are incorrect as they exceed the maximum fill.

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A raceway is filled with 12 AWG copper conductors. What is the maximum allowable fill, according to the 2026 NEC?

A raceway is filled with 12 AWG copper conductors. What is the maximum allowable fill, according to the 2026 NEC?

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