Illustrated Catastrophes: A Shoddy Shore Power Installation

All references are based on the 2020 edition of the NEC.

A Shoddy Shore Power Installation

This photo was sent in by Stephen Pilling, director of operations for Reilly Electrical Contractors, Inc., in North Hampton, N.H. “I thought I would share one of the latest catastrophes we have discovered over the last couple weeks,” said Pilling. “The ‘shore power receptacle’ was found during a visit to New Hampshire’s largest lake.”One of the first problems I noticed here is the improper use of a set-screw type EMT connector. For fittings installed in wet locations like this, Sec. 314.15 requires the fittings to be listed for use in wet locations. For marinas, boatyards, and docking facilities, Sec. 555.34(A)(1) permits Chapter 3 wiring methods that are identified for use in wet locations. The crushed EMT is an indication that a more durable wiring method should have been used here, too. Section 358.12(1) prohibits using EMT in locations where it will be subjected to severe physical damage. Perhaps installing rigid metal conduit (RMC) would have been a better choice, since Sec. 344.10(E) permits RMC to be used where installations are subject to severe physical damage.

Trespassers Beware!

Stephen M. Daniels, owner of Stephen M. Daniels Electrical Contractors of Lancaster, Pa., was kind enough to share this photo with us. “I was doing a service call for a dead circuit (forgive the pun), and took the panel cover off,” said Daniels. “There were missing knockouts, which is how the furry panel guest got in. This is another reason why the Code calls for no open KO in panels or boxes.”I could not agree more. Installing knockout seals is important for many reasons, including keeping trespassers out of the enclosure. Section 110.12(A) makes it clear that unused openings (except mounting holes and other openings such as drainage holes and air vents that are intended for the operation of the equipment) must be closed in a manner that provides protection substantially equivalent to the wall of the enclosure. Sealing up the unused openings also helps keep arcs and sparks from escaping (and possibly igniting) nearby combustible materials. Debris and liquids can also fall into unsealed and unused openings, causing damage to internal parts of the equipment. While the Code rules will not always prevent every critter from finding a way into enclosures, they will help minimize the possibility.