A 480-volt, 3-phase, 4-wire system is installed in a commercial building. What is the minimum grounding electrode conductor size required?

Texas Master exam practice question · Services & Derived Systems

A 480-volt, 3-phase, 4-wire system is installed in a commercial building. What is the minimum grounding electrode conductor size required?

A1/0 AWG
3/0 AWG
C4/0 AWG
D6/0 AWG

Exam tip

Be familiar with the specific grounding conductor requirements for different voltage systems.

Why B is correct

According to 250.66(C), the minimum grounding electrode conductor size for a 480-volt, 3-phase, 4-wire system is 3/0 AWG. The other options are not the minimum required size.

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A 480-volt, 3-phase, 4-wire system is installed in a commercial building. What is the minimum grounding electrode conductor size required?

A 480-volt, 3-phase, 4-wire system is installed in a commercial building. What is the minimum grounding electrode conductor size required?

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