New MC cable that has the bond wire the sane size as the #12 conductor.

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j rae

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New MC cable that has the bond wire the sane size as the #12 conductor. I cant get the conector to fit after I wrap the bond wire back around the jacket . Any help ?? THANKS
 
Nom Deplume said:
It is MCap. The bond wire is a #10 aluminum wire. You don't back wrap it, you are supposed to just cut it off.
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IMO, It was never required per code to be back wrapped, It was just a common practice.
 
Personally I loathe back wrapping but to each his own. As stated just cutting it off solves the connector problem.
 
In your other (now closed) thread, you asked if there was a new requirement that 'MC' have a full sized ground wire. I infer that you were really asking about the bond wire in _AC_ cable.

There isn't a specific requirement for a full size bond wire in _AC_ cable.

_AC_ cables are the one with the bond strip. This bond strip is very skinny and there to make the cable sheath work well as a grounding conductor. 'Normal' AC cables still exist.

MC cables do not have a bond strip. They always have a 'full size' ground wire, but it is a normal full size insulated ground conductor that you bring in to the junction box and terminate appropriately.

I heard somewhere, but cannot find a reference, that you could pull the ground wire into the box with the other conductors, and splice it in the same way that you would for the ground wires in a normal MC cable. This would, of course, eliminate any sort of installation speed benefit from using the MCAP, and you would also need to use splices rated for aluminium conductors. The manufacturer does not recommend this approach, but I don't think that it is prohibited or actually harmful to the safety of the installation.

-Jon
 
He's referring to the newer MCAP type MC cable which employs a bare #10 aluminum conductor in contact with the armor to form the EGC.

MCAP_Wrapping_conductors1.gif


http://www.southwire.com/commercial/MCAPandHCFMCAP.htm
 
In this particular cable, the 'grounding strip' has been replaced with a 'full size' aluminium EGC. By 'full size' I mean an aluminium conductor with the same ampacity as the insulated copper egc that you would find in ordinary MC cable. But this aluminium conductor is placed in contact with the sheath, in place of the 'grounding strip' of an AC cable.

-Jon
 
ron said:
It makes me now think about regular AC cable. I thought the bonding strip was touching the armor already. Now the strip is just a bigger size?
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It is still touching the armor (inside of the cable) but instead of the strip it is a #10 aluminum.
 
Little Bill said:
If this is used in a box that will contain a receptacle, do you have to run a bonding jumper from the box up to the EGC terminal of the receptacle?
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I re-read the instructions it shows that the bonding jumper being installed.

I still don't think it needs the jumper if the receptacle is installed on a metal ring (Pring, or raised cover).
 
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If the box is grounded then you would need either a bonding jumper or a self-grounding receptacle. Switches would not need a bonding jumper nor a self-grounding device. I believe that this MC cable used a larger bonding conductor when compared to AC cable (bonding tape/strip) because AC cable uses a stronger, thicker metal jacket. (At least is always seems that way when I cut it). :roll:
 
I have been told that this cable needs a certain type of rotosplit tool to strip off the armor, and it might be worth mentioning that the fittings must be listed for the cable. I'm not sure if all MC fittings are listed for use with MCap.
 
(Surface mount) NOT required to have a bonding jumper or a self grounding receptacle if the receptacle is mounted directly to the metal box with one fiber washer removed or receptacle installed on a raised cover.

(Recessed mounted) Bonding jumper or a self grounding receptacle IS required when the receptacle is mounted on a recessed box. For example a 4S box with a plaster ring requires a bonding jumper or a self grounding receptacle.
 
infinity said:
If the box is grounded then you would need either a bonding jumper or a self-grounding receptacle. Switches would not need a bonding jumper nor a self-grounding device. I believe that this MC cable used a larger bonding conductor when compared to AC cable (bonding tape/strip) because AC cable uses a stronger, thicker metal jacket. (At least is always seems that way when I cut it). :roll:
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I guess I should have asked does the cable ground/bond the box?

I suppose, to answer my own question, if you have to cut the bare conductor off for it to fit in the connector, it would have to bond both the box and the receptacle.
 
joebell said:
I have been told that this cable needs a certain type of rotosplit tool to strip off the armor, and it might be worth mentioning that the fittings must be listed for the cable. I'm not sure if all MC fittings are listed for use with MCap.
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I really don't think you will find a connector that is not listed for grounding, so they all should be acceptable. They are all rated for both AC or MC cable, and many also for flexible metal conduit.

Little Bill said:
I guess I should have asked does the cable ground/bond the box?

I suppose, to answer my own question, if you have to cut the bare conductor off for it to fit in the connector, it would have to bond both the box and the receptacle.
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Yes, that is a big reason for this design - the cable sheath is the EGC, and proper fittings must be used to provide continuity to the metal enclosures it terminates at.
 
Southwire MCAP requires a connector listed as type MCIA. This would also include integral clamps in metal boxes.

UL approved for use with aluminum interlocking grounding metal clad cable, Type MCIA
(Southwire MCAP?)
MCAP? is a registered trademark of Southwire Company
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