Code Quiz: Ground-Fault Protection of Equipment

What kind of ground-fault testing needs to be done when you install 1,200A service?

Feb. 14, 2019

Question: What testing is required upon initial installation of a 480V/277V 1,200A service?

See the answer below.

Answer: Performance testing of the ground-fault protection system

Explanation: NEC Sec. 230.95(C) requires testing of the ground-fault protection system when first installed on site. The 2017 NEC added the requirement that the test be conducted "by a qualified person(s) using a test process of primary current injection." A written record of this test is required to be made available to the authority having jurisdiction (AHJ). The test button on the ground-fault protective device is not a sufficient test to comply with the testing requirements as it does not prove the system will sense a ground fault, it only shows the system is capable of opening the circuit breaker.

Lupacchino is a senior design engineer with Gaylor Electric, Inc. in Noblesville, Ind. and serves as an alternate on NEC Code-Making Panel No. 3. He is currently licensed in more than 80 jurisdictions. He can be reached at [email protected].

About the Author

John Lupacchino

Senior Design Engineer

John began his career in electrical construction as an apprentice and worked his way through the trade. He is currently licensed in more than 80 jurisdictions. With more than 35 years of experience, he now plays a vital role in Gaylor Electric’s Engineering Department, where he serves as a senior design engineer. With a focus on design engineering, quality assurance, and code compliance, he has earned the highest level of respect from industry professionals alike. John currently serves as an alternate on NFPA 70 Code Making Panel No. 3. In addition, he enjoys sharing his electrical knowledge through education. As an Associated Builders and Contractors instructor, he continues to help grow a new generation of high-performing construction leaders.