What's Wrong Here?

Jan 1, 2004 12:00 PM, By Joe Tedesco, NEC Columnist

Hint: Go ahead, add another extension ring just to be sure the finished installation will be flush with the wall.

David Marcotte, senior electrical designer, Bergmann Associates, Rochester, N.Y., questions the circuit's equipment grounding conductor. “Make sure it stays in the box (250.148),” Marcotte wrote. “I would bet the electrician, or wannabe electrician, was doing this work around the holiday season and was in need of practice for his holiday wrapping. And how about the teledata box in the background? Looks mighty inaccessible to me. Good luck installing a plate on that box.”

Ben Mickler, owner, Benchmark Electric, Inc., Zebulon, N.C., added, “Be sure to check Section 314.20. A box located in a wall with a surface of noncombustible material must be flush or recessed no more than 0.25 inch.”

John Penn Jr., P.E., associate, Steinle Construction Engineers, Inc., Wilmington, Del., would verify compliance with 250.4(A)(3). “Make sure that the grounding conductor is not wrapped around a non-current-carrying conductive material connected to thermoplastic conduits,” he wrote. “This would create a non-effective ground-fault current path.”

Author's note: All winners also noted that the number of extension rings installed isn't a problem as long as the conductors in the box can be extended at least 3 inches outside the opening (300.14).

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