Protecting MC cable from physical damage.

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little george

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If MC cable is installed in a basement of a residential home by running down the cement wall to a box containing a receptacle, is there a need to protect it? Or how about running MC cable down from the ceiling of a residential basement to feed a furnace? Same question.
 
It ultimately comes down to your and/or the AHJ's determination of what may be typically present that may cause physical damage, and really is a judgement call.
 
I believe the wording on Mc is the same as nmc, no advantage as far as physical damage. I often see it run , as if it can take more physical damage, but the code still says that it must be protected.
 
electricianexpress said:
I believe the wording on Mc is the same as nmc, no advantage as far as physical damage. I often see it run , as if it can take more physical damage, but the code still says that it must be protected.
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Wording is same or similar for raceways as well, but each raceway or cable has differences in how much abuse they can take before they become damaged. You may very well find a ENT raceway can take less abuse then some cables before it is damaged and would protect each one differently in different applications.
 
electricianexpress said:
I am not looking at the book however I believe emt is worded severe physical damage
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No, EMT is worded the same as NM is.

But even if all methods were worded the same the AHJ decides if a wiring method is appropriate in a certain area.

For instance in my area I can run NM down a wall into a panel. In other areas the AHJs do not allow that.
 
iwire said:
No, EMT is worded the same as NM is.

But even if all methods were worded the same the AHJ decides if a wiring method is appropriate in a certain area.

For instance in my area I can run NM down a wall into a panel. In other areas the AHJs do not allow that.
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Actually...Type NM Cable can actually be protected from "physical damage" via EMT as described in Section 334.15(B) while EMT is to be protected from "Severe Physical Damage" as stated in Section 358.12(1).
 
MasterTheNEC said:
Actually...Type NM Cable can actually be protected from "physical damage" via EMT as described in Section 334.15(B) while EMT is to be protected from "Severe Physical Damage" as stated in Section 358.12(1).
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and just what is physical damage as opposed to severe physical damage is defined where? IMO both are subject to interpretation and can be looked at differently from one AHJ to the next.
 
Just figured I would add........the crush rating by UL minimums are 1000 lbf for less than 2 AWG and 2000 lbf for 2 AWG and larger for Type MC Cable. It is actually stronger than it is given credit for. That is why educating the Inspectors on what would actually be considered physical damage has to be relevant to the environment. Anything can move from non physical damage or physical damage to even severe physical damage depending on intent.
 
300.4 (D) where installed parallel to framing members in exposed and concealed locations only need protection if within 1 1/4" of framing member edge.
 
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