How well do you know the Code? Think you can spot violations the original installer either ignored or couldn’t identify? Here’s your chance to moonlight as an electrical inspector and second-guess someone else’s work from the safety of your living room or office. Can you identify the specific Code violation(s) in this photo? Note: Submitted comments must include specific references from the 2017 NEC.
Hint: Help support our cause.
October Winners
Several readers were able to correctly identify the problems with this 480V installation. Our three winners this month were: Gary Johnson, a reader from Tempe, Ariz.; Bryan Schroder, an electrical instructor at Northcentral Technical College in Wausau, Wis.; and Ed Geleski, a project engineer with Dooley Electric Co., Inc. in Brooklyn, N.Y.
According to Sec. 250.97, for circuits exceeding 250V to ground, bonding of the raceways to this enclosure must be in accordance with the requirements for service raceways found in Sec. 250.92(B), except for (B)(1). Section 250.92(B) states that bonding jumpers must be used around oversized concentric or eccentric knockouts and standard locknuts must not be the only bonding means. The raceway entry on the left would be required to have a bonding jumper installed from the raceway to the enclosure in order to bond around the remaining rings. For the top raceway entry, standard locknuts would be permitted since the exception in Sec. 250.97 allows four options if oversized, concentric, or eccentric knockouts are not encountered. The bonding options include:
1) Using threadless connectors for metal-sheathed cables.
2) For RMC or IMC installing one locknut inside and one locknut outside.
3) EMT fittings, FMC fittings, or cable connectors with shoulders that seat firmly against the box, with one locknut inside the cabinet.
4) Other listed fittings.