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. It's your turn to identify the violation.
Hint: You're not on the list!
Find the Answer
Section 348.20(A) of the 2011 NEC tells us that flexible metal conduit (FMC) smaller than ½ in. is permitted only for the following five applications.
1) For enclosing motor leads.
2) Maximum of 6 ft lengths for wiring utilization equipment, listed assemblies or luminaire tap connections.
3) Manufactured wiring systems
(4) Hoistway wiring, and
5) Listed assemblies for connecting luminaire sections.
The 3/8 in. FMC in this photo is much longer than 6 ft. In fact, the FMC continues for approximately 20 ft in this installation. It was used to wire a photocell mounted on the outside corner of the building. If there is no equipment ground wire installed inside the FMC then it is also creates a violation of 250.118(5)(c), which places a 6 ft limit on using the FMC as an equipment grounding conductor.
Also, since the FMC is tie-wrapped to the electrical metallic tubing (EMT), there is yet another violation. Section 300.11(B) generally does not permit ½ in. EMT to be used as a support of other raceways.
Lastly, section 348.6 requires FMC to be listed. The FMC used for this installation is not listed.