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Posted By: Mike_Riverside bad practices - 10/26/02 03:26 AM
can i get some input here...

we are working on "hotel style" apartments (retirement place), 74 units in this building. each unit has a 90 amp sub-panel. To feed these panels we ran 2-3 w/gnd sub-feeds. Some runs are as far as 350 feet from the meter room.

Anyways, to the point...the foreman had some helpers strapping the cables every 4 feet, the problem is they are doing the three at a time with zip ties and drywall screws!


Next, all the circits i ran in the corridors (12-2 and 12-3 MC Cable), the foreman had me "strap", all in a bundle, with 2 1/2", 2", or 1 1/2" EMT straps.

there is more... i will try to get som pics.

BTW this guy is the VP of the corperation.
Posted By: sparky Re: bad practices - 10/26/02 11:57 AM
hi Mike_Riverside.
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2-3 w/gnd sub-feeds. Some runs are as far as 350 feet from the meter room.

I'm comming up with roughly 12 volts or 5% drop @ 240....blows the 210.19(A)FPN....

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every 4 feet, the problem is they are doing the three at a time with zip ties and drywall screws!
hmmm, messy...
well ok ..T310.15(B)(2)(a) , given 310.15(B)(4) {kick's the noodles out} means 6 conductors @ 80%. , so per 310.16 starting @ 100a we get 80A.

~This is all assuming it's AL, and bundled per 310.15(B)(2)

~ The other issue is the tie wraps, i believe panduit had obtained a listing in recent years, but i'm not sure as to it's specifics.

~ The EMT straps may be an obvious listing violation to some (110.3(B))

~ 310.15(B)(2) Ex has an 02' change applicable to the derating of 'bundled' MC

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Posted By: harold endean Re: bad practices - 10/26/02 09:07 PM
Maybe they should make up some trapeeze type hangers using Unistrut or Kilndorf, that way they can pull a lot of wires and support them properly. You might not have to worry about bundling either.
Posted By: ShockaRe Re: bad practices - 10/27/02 04:37 AM
if the cables are tie wraped for more than 24 inches togethor, this is considered bundleing Thus you will now need to derate
Posted By: electure Re: bad practices - 10/28/02 01:15 AM
Mike, I was actually taught that the Romexes had to be separated in order to provide for heat dissipation by a Riverside County inspector. Have you had any inspections yet?
(I also cut all the ty-raps off of the wiring inside panels when I find them. They make for a very neat looking job, but when they're all bundled for 24" or more, as mentioned earlier, it becomes a derating problem)
Posted By: Mike_Riverside Re: bad practices - 10/28/02 05:39 AM
sparky: yes, they are AL

electure: we are actually working in Laguna Niguel right now. we have had an inspection, but only on the first floor of this building. All the sub-feeds are run from the meter room to the third (top) floor and then down to the panels on 3, 2, & 1 floors, so the inspector has not seen this yet.
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