MC Cable sleeved in EMT Conduit

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eddie_kerri

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cincinnati, ohio
I am installing (4) dedicated circuits and will be using MC Cable from the panel to each receptacle. I am using surface mounted 4 square boxes with 3/4" EMT that will penetrate a drop ceiling. Can I simply sleeve 12/2 mc cable down the 3/4" EMT conduit or do I have to use an mc connector, grc coupling and connector at the end of the EMT above the ceiling and strip the outer jacket at that point so only the conductors are in the EMT? I think I already know the answer, but I thought I would run in by everybody.
 
Dennis Alwon

Dennis Alwon

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I know the nec allows us to sleeve mc (330.10 (A)(7) and it would appear that if one side is grounded then IMO it can be sleeve directly into the box. I bet I will hear junk about this. :D
 
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iwire

iwire

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eddie_kerri said:
I am installing (4) dedicated circuits and will be using MC Cable from the panel to each receptacle. I am using surface mounted 4 square boxes with 3/4" EMT that will penetrate a drop ceiling. Can I simply sleeve 12/2 mc cable down the 3/4" EMT conduit or do I have to use an mc connector, grc coupling and connector at the end of the EMT above the ceiling and strip the outer jacket at that point so only the conductors are in the EMT? I think I already know the answer, but I thought I would run in by everybody.
Click to expand...

300.10 Electrical Continuity of Metal Raceways and
Enclosures. Metal raceways, cable armor, and other metal
enclosures for conductors shall be metallically joined together
into a continuous electrical conductor and shall be
connected to all boxes, fittings, and cabinets so as to provide
effective electrical continuity. Unless specifically permitted
elsewhere in this Code, raceways and cable assemblies
shall be mechanically secured to boxes, fittings,
cabinets, and other enclosures.

Exception No. 1: Short sections of raceways used to provide
support or protection of cable assemblies from physical
damage shall not be required to be made electrically
continuous.

Exception No. 2: Equipment enclosures to be isolated, as
permitted by 250.96(B), shall not be required to be metallically
joined to the metal raceway.
Click to expand...




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.

Exception No. 1: Short sections of raceways used to provide
support or protection of cable assemblies from physical
damage shall not be required to be mechanically
continuous.

Exception No. 2: Raceways and cables installed into the
bottom of open bottom equipment, such as switchboards,
motor control centers, and floor or pad-mounted transformers,
shall not be required to be mechanically secured to the
equipment.
Click to expand...


I think the above rules out your idea.


Now, can you use a GRC coupling to make a fitting? I have many times, if that is the correct use of listed products is up for debate and an inspector could give you a hard time.

You could use one of these with 1/2"

4058%20REV_edited-1.jpg


4157-dcv2.jpg


Or just put in a box that you don't use for anything more than a coupling for a EMT connector and MC connector, no loop, no splices, no grounding needed. You would have to be able to access the box after the job is done.
 
Dennis Alwon

Dennis Alwon

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But stripping the MC inside the conduit would technically be a code violation. I wonder if anyone has ever been called on that
 
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eddie_kerri

Member
Location
cincinnati, ohio
So if I was to use the fitting that you have posted, can the outer jacket remain on or does it have to be stripped off in the EMT? Either way it seems as though the metal connection is continuous regardless of the outer jacket staying on or being stripped off at the point of using the fitting you have posted. Correct?
 
infinity

infinity

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Dennis Alwon said:
But stripping the MC inside the conduit would technically be a code violation. I wonder if anyone has ever been called on that
Click to expand...

Not always, some MC has individually marked conductors, which IMO like Bob's, are not even required.

Rob%2527s%2520Work%2520044.JPG

Rob%2527s%2520Work%2520045.JPG
 
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FREEBALL

Senior Member
Location
york pa usa
I read the code to say that you can run a piece of mc through a conduit (raceway) to provide support or protection but the mc must still be terminated in the enclosure its entering by an approved connection. So if your running an mc cable into a conduit it has to exit the conduit and terminate into the enclosure with an approved mc fitting.
 
iwire

iwire

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Massachusetts
FREEBALL said:
I read the code to say that you can run a piece of mc through a conduit (raceway) to provide support or protection but the mc must still be terminated in the enclosure its entering by an approved connection. So if your running an mc cable into a conduit it has to exit the conduit and terminate into the enclosure with an approved mc fitting.
Click to expand...

I am going to ask you for a code section requiring that.
 
roger

roger

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Fl
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copper chopper said:
how would stripping it be a violation, then wouldnt romex in that same situation is also
Click to expand...
The conductors of NM are not identified, so it would be a violation to use them outside the sheathing, MC conductors are identified so it would be fine.

Roger
 
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