Terminating EGC's when using 12/2 MC

[GoldDigger]

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AC does not have an insulated equipment ground.
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So my questions. If I have a cable with a bonding strip and insulated equipment ground, is that cable AC or MC?
Why are there no fittings available for AC that avoid the use of insulated bushings?

Make that "some AC does not have an insulated equipment ground". You can get it with IG for hospital or other purposes.
That still does not tell you for sure what you have.

 

[Greg1707]

AC or MC

AC or MC

Make that "some AC does not have an insulated equipment ground". You can get it with IG for hospital or other purposes.
That still does not tell you for sure what you have.

Thanks for the response. What is the difference between AC with insulated equipment ground or MC with bonding strip?

 

[Article 90.1]

I'll tell you a difference between MC and AC cable that is often overlooked. Type AC provides mechanical protection; type MC does not.

As someone else said you can get AC with a ground, but I will add that you can AC with a ground that is not hospital grade as well as hospital grade.

Either wiring method used, better watch your connections as some are listed MC, some AC and some both or more.

I'm in agreement with another poster that leave one green long, bond your box and bring the EGC on to the splice or device.

I see a lot of installers only use single cable connectors instead of two cable connectors, which is more labor and greater box fill.

Another common error I find with MC cable is using the insulated green wire as a CCC; thus effectively leaving the cable without a low impedance ground fault return path.

To the OP, it is your license on the line as well as far as the lawyers and judges would be concerned should a problem arise. I f I was working for a friend and they told me not to use anti short bushings or to not bond the first box when transitioning from an existing wiring method to MC cable I would just do it anyway.

 

[goldstar]

I'll tell you a difference between MC and AC cable that is often overlooked. Type AC provides mechanical protection; type MC does not.

As someone else said you can get AC with a ground, but I will add that you can AC with a ground that is not hospital grade as well as hospital grade.

Either wiring method used, better watch your connections as some are listed MC, some AC and some both or more.

I'm in agreement with another poster that leave one green long, bond your box and bring the EGC on to the splice or device.

I see a lot of installers only use single cable connectors instead of two cable connectors, which is more labor and greater box fill.

Another common error I find with MC cable is using the insulated green wire as a CCC; thus effectively leaving the cable without a low impedance ground fault return path.

To the OP, it is your license on the line as well as far as the lawyers and judges would be concerned should a problem arise. I f I was working for a friend and they told me not to use anti short bushings or to not bond the first box when transitioning from an existing wiring method to MC cable I would just do it anyway.

All good points. I didn't want to just come out and say my friend is a hack. But, the fact of the matter is - he's a hack !!! There, I said it. As far as the lawyers go, I'm working under my friend's license and not mine. I'm his employee for this project. The fact that he shows up on the job without green ground screws does that make me liable just because I have my own license ? I would have evaluated this project differently if I were the prime contractor and especially if I had done work in this building before. But, I'm not and I bear no liability. If I thought this was a life or serious personal safety issue there would have been an argument.

 

[iwire]

Type AC provides mechanical protection; type MC does not.

Can you explain the difference you see here?

 

[Greg1707]

further explanation of difference of AC vs MC

further explanation of difference of AC vs MC

Ok. Let me rephrase my questions. Suppose I have in front of me two cables.

One is AC with an insulated equipment ground and the other is MC with a bonding strip (makes the outer sheath an equipment ground).

Which would you prefer to use?

 

[kwired]

I have not used any AC cable in years. The more recent development of MCAP or other similar products does make one question what is the difference between AC and MC cables.

I think the answer possibly lies within construction requirements. One thing I did notice long ago but not sure if still applies is AC always had paper based fillers inside the sheath, MC always had plastic fillers - it is possible that is about the only major thing that separates them.

 

[iwire]

Suppose I have in front of me two cables.

One is AC with an insulated equipment ground and the other is MC with a bonding strip (makes the outer sheath an equipment ground).

Which would you prefer to use?

For productivity, speed etc MC with a bonding strip.


For better grounding, or meeting job specs requiring copper EGCs it would be the AC.