mc in plastic boxes

[nolabama]

im sure i could tap a hole in a plastic box - probably easier than a metal one
just dont know how those threads would hold up

 

[George Stolz]

The greatest issue I have with using the z-clips in nonmetallic boxes such as these...

...is that installers will turn a keyless around so that the neutral contacts the grounding conductor so that the breaker won't trip from the keyless' ungrounded terminal contacting the grounding screw of the box.

 

[Wire_nutz]

Definitely an abnormal situation.

First of all I'm not aware of any switch and outlet nonmetallic box manufacture, that the clamps in the box are designed for anything other than nonmetallic sheathed cable.

If you could find an approved threaded mc connector that would penetrate the plastic box with enough threads to install a ground bushing with wire clamp and bond ground conductors together.

 

[iwire]

Definitely an abnormal situation.

First of all I'm not aware of any switch and outlet nonmetallic box manufacture, that the clamps in the box are designed for anything other than nonmetallic sheathed cable.

They sell plastic boxes with 1/2 KOs and the NEC tells us how to handle MC with plastic boxes, I do not see any issue. :smile:

 

[mdshunk]

First of all I'm not aware of any switch and outlet nonmetallic box manufacture, that the clamps in the box are designed for anything other than nonmetallic sheathed cable.

You need to get out more.

 

[celtic]

You need to get out more.

...sez the man with 11k + posts

 

[Pierre C Belarge]

They sell plastic boxes with 1/2 KOs and the NEC tells us how to handle MC with plastic boxes, I do not see any issue. :smile:

I am not sure what your answer means.

Are you stating that a plastic box with a 1/2' KO is suitable for use with MC cables?

 

[quogueelectric]

330.40 Boxes and Fitting Fittings used for connecting type MC cable to boxes,cabinets,or other euipment shall be LISTED AND IDENTIFIED for such use.

 

[peter d]

Are you stating that a plastic box with a 1/2' KO is suitable for use with MC cables?

Yes, that's exactly what he's saying.

Throw a bonding bushing on the connector(s) and call it a day. Obviously this is silly in most cases but there may be a situation where it might have to be done, like transitioning MC cable to a PVC box to go to an underground raceway.

 

[ctmike]

Yes, that's exactly what he's saying.

Throw a bonding bushing on the connector(s) and call it a day. Obviously this is silly in most cases but there may be a situation where it might have to be done, like transitioning MC cable to a PVC box to go to an underground raceway.

I would think in this instance you would need a metal box to attach your raceway to

 

[peter d]

I would think in this instance you would need a metal box to attach your raceway to

In which instance? If I put a bonding bushing on the MC connector and connect an EGC to it, I am code compliant.

 

[quogueelectric]

In which instance? If I put a bonding bushing on the MC connector and connect an EGC to it, I am code compliant.

Not so fast there Pete. What specific connector do you have that is listed and identified for use with plastic boxes. I just fired off a question to the bridgeport fitting co to see if they made any.

 

[peter d]

Not so fast there Pete. What specific connector do you have that is listed and identified for use with plastic boxes. I just fired off a question to the bridgeport fitting co to see if they made any.

Uh oh..not the listing stuff again. That means I couldn't drill out a PVC box and put a NM connector in it, because the connector is probably not listed for it. But how else would you transition a cable method to a PVC j box?


Sometimes we have to use common sense, right?

 

[quogueelectric]

Uh oh..not the listing stuff again. That means I couldn't drill out a PVC box and put a NM connector in it, because the connector is probably not listed for it. But how else would you transition a cable method to a PVC j box?


Sometimes we have to use common sense, right?

Thats not what 330.40 says in 2005 I did not check 2008 yet it is out in the truck.

 

[peter d]

Thats not what 330.40 says in 2005 I did not check 2008 yet it is out in the truck.

I don't see how 330.40 precludes me from connecting MC cable to a PVC box as long as the fitting is listed for use with MC cable.

 

[quogueelectric]

I don't see how 330.40 precludes me from connecting MC cable to a PVC box as long as the fitting is listed for use with MC cable.

Listed and identified for such use.
a connector connects 2 things one being the mc cable which we all know it is listed for.
The other thing would be a box.
I am reserving judgement until I hear from bridgeport mfg co probably on monday.

 

[peter d]

Listed and identified for such use.
a connector connects 2 things one being the mc cable which we all know it is listed for.
The other thing would be a box.
I am reserving judgement until I hear from bridgeport mfg co probably on monday.

You can live in the fantasy land of listings. I'll live in the world of using common sense when using connectors. And common sense tells me it's fine to use an MC connector in a plastic box with the proper bonding means applied to it.

 

[nolabama]

from another thread - this specific AHJ addresses this very issue :grin
http://forums.mikeholt.com/attachment.php?attachmentid=2571&d=1228000762

 

[electricmanscott]

You can live in the fantasy land of listings. I'll live in the world of using common sense when using connectors..

How dare you!

 

[electricmanscott]

Not so fast there Pete. What specific connector do you have that is listed and identified for use with plastic boxes. I just fired off a question to the bridgeport fitting co to see if they made any.

What kind of connector would you use with this box?