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Posted By: Joe Tedesco This MC Cable is Subject to Damage - 12/04/02 09:35 PM
[Linked Image]

What rule covers the necessary protection where this MC Cable is run on an outside brick wall in this manner.

Sent in from someone who needs qualified answers.
Posted By: sparky Re: This MC Cable is Subject to Damage - 12/04/02 10:23 PM
Quote
300.4(E) Cables and Raceways Installed in Shallow Grooves. Cable- or raceway-type wiring methods installed in a groove, to be covered by wallboard, siding, paneling, carpeting, or similar finish, shall be protected by 1.6 mm (1/16 in.) thick steel plate, sleeve, or equivalent or by not less than 32 mm (11/4 in.) free space for the full length of the groove in which the cable or raceway is installed.

Exception: Steel plates, sleeves, or the equivalent shall not be required to protect rigid metal conduit, intermediate metal conduit, rigid nonmetallic conduit, or electrical metallic tubing.
330.10 (A)(11) Allows MC cable "embedded in plaster finish on brick or other masonary except damp and wet locations". I've seen this done and accepted this way. Come to think of it I have done this in some buildings in Boston. I think this is ok but I am open to opinions otherwise.
Posted By: spyder Re: This MC Cable is Subject to Damage - 12/05/02 02:19 AM
If they used Romex I would have a problem with it. I think MC is fine here. The alternative is wiremold or conduit.
Posted By: RSmike Re: This MC Cable is Subject to Damage - 12/05/02 01:59 PM
I've always wondered about that 1/16" plate thing. On a bad day I could easily drive a nail through a 1/16" piece of steel. My brad nailer would easily shoot through 1/16"...probably thicker....

I've been bad because I've buried romex in brick walls...but I'm thinking of placing little tiny "CAUTION: Buried Cable" flags in the wall where the wire is embedded. I did manage to take pictures of where the wires were placed for future reference. Now if I could only find the pictures. Next time I'm going to use some form of conduit.

I also make sure to never shoot brad nails directly under an outlet. There's always that slim possibility that a wire might be nearby. Plus air-driven nails have a strange way of making detours as they enter wood or brick.

RSSorry,
RSmike
Posted By: Texas_Ranger Re: This MC Cable is Subject to Damage - 12/05/02 04:59 PM
This looks exactly like how wiring is done in central europe. Except for the fact we only use Romex. And we usually plaster it over and don't just leave it exposed. *grin*
Here in Austria I have wired entire rooms like that. We once used to have some kind of flat Romex, (NYIF) (looked like zip cord, only double-sheathed and with more space between the conductors) which should ensure that any nail or screw driven into the cable wouldn't result in an arcing short. However, it costs 10 times as much as standard round 2 wire w/ ground Romex (NYM 3x1.5), so it starts to die out, which is a real pity.
Posted By: SvenNYC Re: This MC Cable is Subject to Damage - 12/05/02 05:03 PM
Is this groove cut directly into the masonry or is this just a space in between the plaster/lath and the brick wall?

If it's a groove in the masonry itself, I would say use conduit and fish wires through it - and use a masonry box as one of you guys told me some time in the recent past. [Linked Image]

Colombian-style wiring for solid masonry houses (popular down there) is done using conduit and fishing individual conductors through the pipe.

Burying cable like that probably makes it a bear to replace in the future.

Just my opinion, but I'm not a licenced electrician.

[This message has been edited by SvenNYC (edited 12-05-2002).]
Posted By: HotLine1 Re: This MC Cable is Subject to Damage - 12/06/02 01:38 AM
Joe:
The method in the pic was a common item in the New York City and Metro NJ, in older buildings. The "older" stuff was BX. The only concern that I would have is if the MC is aluminum armor (sheath) it could/can corrode in contact with the masonry and dampness. My NEC is in my truck, and it's snowing, so...I'll consult the bible in the AM
John
Posted By: Va Sparky Re: This MC Cable is Subject to Damage - 12/12/02 03:05 AM
Like Hotline, my bible isnt with me,but if Im not mistaken ( which I have been before) MC is ok for cinder filled or placement in old work on masonary walls.(Meaning not EMBEDDED in concrete or masonary) I've also argued the point to an inspector that protection is required all points that pass through or are attached to the building structure within an 1 1/4 inch.This would include studs @ 24 or 16 inch centers meant for drywall or covering, sill plates, and bottom plates. Add a stud for your switch box and it technically doesnt need a nail plate because its not intended for wall covering.This is only an agrumentative point and not a common practice, though. Bottom line is you need to protect your work. The biggest promblem I see in the pic is I dont think the MC can be embedded in the plaster that is going to patch the wall.
Posted By: John Steinke Re: This MC Cable is Subject to Damage - 12/13/02 12:49 AM
I think that some of the other comments are on the right track- this looks a lot like standard European practice (only better).
And you wonder why I question the possibility of an "international" code?
VA sparky, read my post above regarding the plaster.
Posted By: Texas_Ranger Re: This MC Cable is Subject to Damage - 12/13/02 07:54 PM
Why better than European practice? In Austria we mostly use conduit for this type of work. But it wouldn't be the lkeast of a problem or evenb unusual to bury Romex like the MC in the picture.
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