MC Cable for Branch Circuits

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The superintendent on the job is differing from my opinion on the "allowability" of MC cable in the walls I will paste the job specs below. I am not reading that MC cable is not allowed in the walls for receps etc. I believe he is reading into the Raceway section of the job specs about emt inside interior wall. I believe that since that it under the "Raceway" section of the specs it is only dealing with raceways themselves and not wiring methods, and it is my understanding that MC cable is not a raceway. Below are the pertinent specs. There is also the "shall be primarily used as whips", but all mc restricted jobs I have ran listed it as ONLY or under the "do not use". What is your professional opinions on this?

SECTION 260519 - LOW-VOLTAGE ELECTRICAL POWER CONDUCTORS AND CABLES

PART 2 - PRODUCTS

2.3 METAL-CLAD CABLE, TYPE MC
A. Description: A factory assembly of one or more current-carrying insulated conductors in an
overall metallic sheath. MC cable shall include grounding conductor.
B. Shall primarily be used as whips for connections to equipment and lighting not to exceed 6ft in
length.



2. Do Not Use MC Cable for the Following:
a. Homeruns to panelboards.
b. Where exposed to view.
c. Where exposed to damage.
d. Hazardous locations.
e. Wet locations.
f. When restricted otherwise above, and when specifically disallowed by the local
AHJ or Owner.
g. Circuits supplied by an emergency or standby power source.


3. Aluminum sheathing for MC Cable is not allowed.


SECTION 260533 - RACEWAYS AND BOXES FOR ELECTRICAL SYSTEMS

PART 3 - EXECUTION
3.1 RACEWAY APPLICATION
B. Indoors: Apply raceway products as specified below unless otherwise indicated:
1. Exposed, Not Subject to Physical Damage: EMT.
2. Exposed, Not Subject to Severe Physical Damage: EMT unless noted otherwise.
3. Exposed and Subject to Severe Physical Damage: GRC. Raceway locations include th
following:
a. Loading dock.
b. Corridors used for traffic of mechanized carts, forklifts, and pallet-handling units.
c. Mechanical rooms.
d. Gymnasiums.
4. Concealed in Ceilings and Interior Walls and Partitions: EMT.
 
B. Shall primarily be used as whips for connections to equipment and lighting not to exceed 6ft in
length.


I find this statement confusing the specifications, It seems to be limiting the use of MC cable

If the statement said:
In exposed areas, or installed in accessible ceilings,
Shall primarily be used as whips for connections to equipment and lighting not to exceed 6ft in length,


Edit: the specifications disallow it exposed to view
 
I think I get what you are saying if you put your idea in front of the problem sentence it makes a lot more sense.

B. I
nstalled in accessible ceilings ,Shall primarily be used as whips for connections to equipment and lighting not to exceed 6ft in length.

I believe the intent of that would be that they did not want a bunch of daisy chaining of light fixtures, and that would harmonize with the other specs.

I will say "primarily" is an odd word for a spec book.
 
" Shall primarily be used as whips for connections to equipment and lighting not to exceed 6ft in
length."

Seeing as that is the only line describing MC's allowed usage.....that's it.
The 6ft requirement kills any idea of running it for receptacles down the wall.

How was the job bid? All MC, or per the above quote?
Welcome to low bidder land.
This should have been clarified prior to bidding. It wouldn't hurt to try and get a clarification from the EE after the fact.

....good luck
 
Sounds like the whole job (except for whips) is to be done in EMT unless subject to physical damage. Pretty standard in some buildings.
 
I didn't think part 3 would apply because it is dealing with raceway specifications and mc cable is not a raceway. I think it is odd to include a list of places you aren't allowed to use mc, if you aren't allowed to use it at all.
"2. Do Not Use MC Cable for the Following:
a. Homeruns to panelboards."

All pipe only job specs I have seen say outright "no mc cable" and then list fixture whips as an exception. The estimator is saying "it doesn't exclude mc cable". It is out of my department now, but I wanted to see what you guys think, I get where the estimator is coming from, but I also think the engineers copy and paste all this stuff and who knows what they intended.
 
By not including mc with the pipe it is therefore excluded in use. The exception is as a whip to fixtures, motors etc.
 
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