All references are based on the 2020 edition of the NEC.
Handyman Special
Doug Carver, a senior engineer with Impulse Electric, Inc. in Salt Lake City, was kind enough to share these photos with us. He discovered some questionable wiring while troubleshooting power problems at his sister’s home in southern Missouri. In Doug’s own words, “I noticed a serious issue with how the ‘handyman’ ran feeder wires. The first thing I noticed (besides the obvious lack of NMB connectors) is that the bare ground conductor was being used as a neutral. No connector at the top of the panel, conductors are not in conduit, and the building is metal sided with a bare dirt floor below the panel. I immediately had them shut off the power at the meter. The feeders enter the ground at the meter in PVC, so I asked them to trace the wires back from the panel to where they enter the shed. After moving a bunch of debris, they found the spot where the feeders enter. The conductors were lying on the ground under a pile of left-over metal siding. As the picture shows, the bare conductor that was carrying the ‘neutral’ load was burned in half.” Among many other violations, the lack of connectors on the NM cables entering the cabinet violates Sec. 312.5(C). Section 300.3(A) requires the individual feeder conductors to be installed in Chapter 3 wiring methods such as raceways or cables
Questionable Wiring Methods
While MC cable is a very versatile wiring method and can be used in many different types of installations, the choice made by the installer to use this type of MC cable in this outdoor wet location may need to be reevaluated. Section 330.10(A)(3) does permit MC cable to be installed indoors or outdoors; however, Sec. 330.10(A)(11) permits MC cable in wet locations only when a corrosion-resistant jacket is provided over the metal covering — and either the metal covering is impervious to moisture, a moisture-resistant jacket is provided under the metal covering, or the insulated conductors under the metal covering are listed for use in wet locations. The choice of cable connectors is questionable, too, as they do not appear to be rated for use in wet locations as specified in Sec. 314.15. Misusing connectors in this way would also be a violation of Sec. 110.3(B). Some of the connectors are not “placed to prevent moisture from entering or accumulating within the box” as required by Sec. 314.15.
