Clamped Destruction

Unfortunately, this isn’t the first time we’ve seen an installation like this. It’s seems obvious that whoever installed this clamp did so to keep the tabs squeezed tight enough to hold the switch blades in place. I think a review of Sec. 110.3 of the 2011 NEC is in order.

More specifically, 110.3(A) states: “In judging equipment, considerations such as the following shall be evaluated:

  1. Suitability for installation and use in conformity with the provisions of this Code.
  2. Mechanical strength and durability, including, for parts designed to enclose and protect other equipment, the adequacy of the protection thus provided.
  3. Wire-bending and connection space.
  4. Electrical insulation.
  5. Heating effects under normal conditions of use and also under abnormal conditions likely to arise in service.
  6. Arcing effects.
  7. Classification by type, size, voltage, current capacity, and specific use.
  8. Other factors that contribute to the practical safeguarding of persons using or likely to come in contact with the equipment.”

I think all of these references apply to this situation.


This High-Flying Act Doesn't Impress

“While walking through a remodel in one of our buildings, this caught my eye,” says Jeff, a government employee and master electrician. “This was someone’s idea of how best to expand the system from an existing junction box. Notice the three nipples supporting the new junction box and lack of any other type of support. In addition, I personally love the 6-in. pipe extension. I guess one stick of conduit would have put them over budget.”

The violations here are evident. All we need to do is call attention to some simple rules that are listed in many sections of the 2011 NEC. For example, as noted in 110.12, “Electrical equipment shall be installed in a neat and workmanlike manner.” An Informational Note adds, “Accepted industry practices are described in ANSI/NECA 1-2006, Standard Practices for Good Workmanship in Electrical Contracting, and other ANSI-approved installation standards.”

We could also point to a number of other missteps by reviewing the requirements in Art. 314.