Type NM Cable Installation in FMC

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rwilsond

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Orange County, CA 19 years of exp.
My General Contractor promised me a quality code-compliant installation. But they seem to me to be better at carpentry and plumbing, than electrical. This installation consists of three Type NM, #14/2 AWG cables "sleeved" in Flexible Metallic Conduit (FMC) for protection from damage. These cables leave the wall, and enter kitchen cabinets for connection to receptacles for the under-counter items (Garbage Disposer & Dishwasher), and the receptacles that serve the counter-top). They're telling me that this installation is perfectly code-compliant, and I should be happy with it. However, I believe this installation has the following issues at a minimum:

1) No more than one of these cables can enter into a 1/2" FMC (due to cross-section and heating considerations). Thus, another FMC must be added, and one of the cables transferred to it.

2) A bushing is required at the taped ends of the FMCs.

3) The ends of the FMCs must be inserted into the wall.

4) Each FMC must be secured within 12" of entering the cabinet.

Additionally, I would like to tell them that the cables and FMCs must all be terminated into/onto one or more electrical boxes on or within the wall, with adequate fittings, but I am unable to find such a requirement within the NEC.

Please tell me if any of my NEC interpretations are off-base, and of anything that I missed.
 

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rwilsond said:
This installation consists of three Type NM, #14/2 AWG cables and the receptacles that serve the counter-top). They're telling me that this installation is perfectly code-compliant, and I should be happy with it.

Additionally, I would like to tell them that the cables and FMCs must all be terminated into/onto one or more electrical boxes on or within the wall, with adequate fittings, but I am unable to find such a requirement within the NEC.

Please tell me if any of my NEC interpretations are off-base, and of anything that I missed.
Click to expand...

I do not know how a 15 amp circuit ("Type NM, # 14/2 AWG") could supply a small appliance branch circuit for the kitchen counter receptacles
 
I'm surprised this thread has promoted a lively discussion by now.
First off, I agree with david, if one or more circuits serve outlets that supply the countertop they should be on a small appliance branch circuit rated 20 amps which would not allow #14 NM.
From that point I find the subject more controversial.
Is it a "run" of raceway or or we simply "sleeving" the NM ?
There appears to be no length limit on a raceway "sleeve", nor do I see a definite requirement concerning termination. In addition 250.86 exempts FMC from being grounded when used as for "cable protection"
You already noted the support issue. Beyond that, and davids note, i hate the lack of connectors or means to provide a smooth transition and I don't care for the FMC not being grounded but, as an inspector, I would be unable to cite it as a violation unless we learn otherwise by subsequent posts.
 
The protection provided by the sleeve is incomplete unless the space where the NM is exposed in the pictures is unaccessible or at least less accessible.
Big question: do full and derating limits apply to sleeves and not just raceways?
I see no practical reason why they should not, but I am not sure the code language covers it.
If you consider the FMC likely to become energized it needs to be bonded.
Without bushings, is it likely enough to become energized?
 
david said:
I do not know how a 15 amp circuit ("Type NM, # 14/2 AWG") could supply a small appliance branch circuit for the kitchen counter receptacles
Click to expand...

Upon further inspection, the two cables entering a common FMC are #12 AWG (this was good news). These 2 cables will serve the counter-top receptacles.

Another question: are the FMCs required to be inserted through the drywall? (the contractor says No).
 
rwilsond said:
Upon further inspection, the two cables entering a common FMC are #12 AWG (this was good news). These 2 cables will serve the counter-top receptacles.

Another question: are the FMCs required to be inserted through the drywall? (the contractor says No).
Click to expand...

A lot of it boils down to what is and if "physical damage" can occur. Many folks seem to think NM cant be exposed, but 334.15 clearly allows it. The "to follow surface" clause might be your best shot at a violation.
 
Is that old NM that you claim as 12 guage? ( prior to 2001 before yellow color)
 
GoldDigger said:
The protection provided by the sleeve is incomplete unless the space where the NM is exposed in the pictures is unaccessible or at least less accessible.
Big question: do full and derating limits apply to sleeves and not just raceways?
I see no practical reason why they should not, but I am not sure the code language covers it.
If you consider the FMC likely to become energized it needs to be bonded.
Without bushings, is it likely enough to become energized?
Click to expand...

The triangular space will be covered by wood and a counter-top, so it will be inaccessible. It does seem possible to me that an FMC could become energized - e.g., if the cable were damaged during installation. Although I believe the FMCs 'should' be bonded - I did not see a Code requirement for this. However, for this installation, the other ends of the FMCs will connect to metal boxes that are bonded to the Equipment Grounding Conductors of the respective cables. And, I definitely want the bushings.
 
rwilsond said:
This installation consists of three Type NM, cables "sleeved" in Flexible Metallic Conduit (FMC) for protection from damage. These cables leave the wall, and enter kitchen cabinets .
Click to expand...

rwilsond said:
The triangular space will be covered by wood and a counter-top, so it will be inaccessible.
Click to expand...


My thought is they were not concerned that the NM-B cable is exposed as shown in the picture. I think they may only intend to provide protection for the cable portion under the counter.

I do agree that they need to provide bushings on the ends of the flex. There may be bushings that I am not seeing under the electrical tape on the flex ends in the picture.
 
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