Code Quiz: Sizing of Grounded Conductor

July 6, 2017
NEC Rules for Sizing Grounded Conductors

Fill in the blank. When sizing a grounded conductor (installed in a single raceway) for a service-supplied alternating current system with a grounded conductor at the service point, the grounded conductor shall not be smaller than the required __________ conductor but shall not be required to be larger than __________. This system is operating over 1,000V.

A) grounding electrode / largest ungrounded service-entrance conductor(s)
B) main bonding jumper / supply-side bonding jumper
C) system bonding jumper / main bonding jumper
D) equipment grounding / intersystem bonding jumper

Scroll Down to See the Answer

Answer: A

As outlined in Sec. 250.186(A)(1), when sizing a grounded conductor (installed in a single raceway) for a service-supplied alternating current system with a grounded conductor at the service point, the grounded conductor shall not be smaller than the required grounding electrode conductor but shall not be required to be larger than the largest ungrounded service-entrance conductor(s).

Owen is the owner and president of National Code Seminars and the holder of master electrician certifications in 46 states. He can be reached at [email protected].

About the Author

Steven Owen

Voice your opinion!

To join the conversation, and become an exclusive member of EC&M, create an account today!

Sponsored Recommendations

Electrical Conduit Comparison Chart

CHAMPION FIBERGLASS electrical conduit is a lightweight, durable option that provides lasting savings when compared to other materials. Compare electrical conduit types including...

Considerations for Direct Burial Conduit

Installation type plays a key role in the type of conduit selected for electrical systems in industrial construction projects. Above ground, below ground, direct buried, encased...

How to Calculate Labor Costs

Most important to accurately estimating labor costs is knowing the approximate hours required for project completion. Learn how to calculate electrical labor cost.

8 Types of Electrical Conduit and Their Uses

Electrical conduit is a tube or raceway used to house and protect electrical wires within a building or structure. From data centers to underground subways to ports and bridges...