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].