A commercial building has a 3-phase, 4-wire, 480V service. The neutral conductor has a 1/0 AWG copper conductor. What is the minimum grounding electrode conductor required for this service?

Texas Master exam practice question · Calculations & Theory

A commercial building has a 3-phase, 4-wire, 480V service. The neutral conductor has a 1/0 AWG copper conductor. What is the minimum grounding electrode conductor required for this service?

A3/0 AWG copper
4/0 AWG copper
C1/0 AWG copper
D2/0 AWG copper

Exam tip

Always refer to 250.66 for the minimum grounding electrode conductor requirements based on the service voltage and type.

Why B is correct

According to 250.66(A), the grounding electrode conductor must be at least 4/0 AWG copper for a 3-phase, 4-wire, 480V service. This ensures proper grounding and bonding for the service.

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A commercial building has a 3-phase, 4-wire, 480V service. The neutral conductor has a 1/0 AWG copper conductor. What is the minimum grounding electrode conductor required for this service?

A commercial building has a 3-phase, 4-wire, 480V service. The neutral conductor has a 1/0 AWG copper conductor. What is the minimum grounding electrode conductor required for this service?

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