LNFC used as protection for GEC

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Steelhead

Senior Member
Location
Southeastern Wisconsin
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Industrial Maint/Journeyman
In several areas in our plant LNFC has been used to protect the GEC coming from transformers to building steel. This has been done by several reputable electricians over the years. In looking at 250.64(B) in the 2011 NEC I don't see LNFC listed as an approved raceway. Were these raceways installed when they shouldn't have been? Or am I missing something?
 
I don't think so

(B) Securing and Protection Against Physical Damage.
Where exposed, a grounding electrode conductor or its enclosure
shall be securely fastened to the surface on which it is
carried. Grounding electrode conductors shall be permitted to
be installed on or through framing members. A 4 AWG or
larger copper or aluminum grounding electrode conductor
shall be protected if exposed to physical damage. A 6 AWG
grounding electrode conductor that is free from exposure to
physical damage shall be permitted to be run along the surface
of the building construction without metal covering or protection
if it is securely fastened to the construction; otherwise, it
shall be protected in rigid metal conduit RMC, intermediate
metal conduit (IMC), rigid polyvinyl chloride conduit (PVC),
reinforced thermosetting resin conduit (RTRC), electrical metallic
tubing EMT, or cable armor. Grounding electrode conductors
smaller than 6 AWG shall be protected in (RMC),
IMC, PVC, RTRC, (EMT), or cable armor. Grounding electrode
conductors and grounding electrode bonding jumpers
shall not be required to comply with 300.5.
Click to expand...
 
If a raceway is needed for protection from physical damage then you need a raceway on the list that Dennis posted. If it's just to look pretty then you can use whatever you want.
 
Steelhead said:
In several areas in our plant LNFC has been used to protect the GEC coming from transformers to building steel. This has been done by several reputable electricians over the years. In looking at 250.64(B) in the 2011 NEC I don't see LNFC listed as an approved raceway. Were these raceways installed when they shouldn't have been? Or am I missing something?
Click to expand...

read carefully what it actually says.

if it is #4 or larger it only requires protection if exposed to physical damage. what form the protection takes is unstated. thus I would suggest LFNC is adequate. On the other hand, if installed appropriately it won't be subject to physical damage so no protection is required.

if it is #6 it does not require metallic protection if secured to the surface of the structure and not subject to physical damage. so again, LFNC would seem acceptable.

if it is #6 if either subject to physical damage, or not attached to the building surface it has to be run in one of the 6 allowed ways.

if it is smaller than #6 it is required to be protected in one of the 6 allowed ways.

common practice in some areas may be to do more than what the code actually requires.
 
infinity said:
If a raceway is needed for protection from physical damage then you need a raceway on the list that Dennis posted. If it's just to look pretty then you can use whatever you want.
Click to expand...

This is done all the time on cell sites. It's #2cu and everywhere it's exposed they sleeve it. Why? Who knows. It gives somebody a good feeling.
 
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