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What's Wrong Here?

Apr 13, 2007 2:50 PM, By Joe Tedesco

Hint: What is physical damage?

I ran across this situation in a major car rental parking lot while waiting for my shuttle back to the airport. I’m guessing the products were probably damaged by a snowplow. However, it really doesn't matter what the reasons were for this "physical damage” to these raceways. The key issue is they were originally installed in the wrong place! It’s obvious the subject of so-called physical damage was never considered when these raceways were first installed.

I can only say that the following rules seem to have been ignored during installation:

110.27 Guarding of Live Parts, (B) Prevent Physical Damage. “In locations where electric equipment is likely to be exposed to physical damage, enclosures or guards shall be so arranged and of such strength as to prevent such damage.”
300.4 Protection Against Physical Damage. “Where subject to physical damage, conductors shall be protected.”
300.5 Underground Installations, (D) Protection From Damage, (4) Enclosure or Raceway Damage. “Where the enclosure or raceway is subject to physical damage, the conductors shall be installed in rigid metal conduit, intermediate metal conduit, Schedule 80 rigid nonmetallic conduit, or equivalent.”
300.12 Mechanical Continuity — Raceways and Cables. “Metal or nonmetallic raceways, cable armors, and cable sheaths shall be continuous between cabinets, boxes, fittings, or other enclosures or outlets.”

Article 352 — Rigid Nonmetallic Conduit: Type RNC

352.10 Uses Permitted. “The use of RNC shall be permitted in accordance with 352.10(A) through (H). FPN: Extreme cold may cause some nonmetallic conduits to become brittle and therefore more susceptible to damage from physical contact.”
352.10(F) Exposed. “RNC shall be permitted for exposed work where not subject to physical damage if identified for such use.”
352.12 Uses Not Permitted. “RNC shall not be used under the following conditions. (C) Physical Damage. Where subject to physical damage unless identified for such use.”