ECN Forum
Posted By: skidmark code question - 08/27/03 10:21 AM
I saw a resedential panel in which the electrician had pulled all of the circuits thru a piece of 2 inch pvc conduit. Isn't this a code violation and if so where is it in the 2002 N.E.C.?
Posted By: Ron Re: code question - 08/27/03 11:05 AM
Unless there was damage to the conductors, I don't think it's a violation. Why do you?
Posted By: Redsy Re: code question - 08/27/03 11:12 AM
Although there are exceptions, this practice would be a violation of the basic rule of 312.5(C).
However, this tpye of installation does seem to be common in some areas of the country.
Posted By: GEO Re: code question - 08/27/03 01:46 PM
as stated there are exceptions.
this is allowed provided you meet those conditions.
Posted By: Tom Re: code question - 08/27/03 01:49 PM
Unless there were very few cables involved, I don't see how this installation could be in compliance with the previously mentioned 312.5(C). I've measured a few brands of Romex & depending on the wire gauge, the limit could be as few as 5 cables in a 2" PVC. Also, very often the requirement for derating is overlooked in this type of installation.

Tom
Posted By: Ron Re: code question - 08/27/03 10:43 PM
Fill derating does not apply if it the conduit is installed for protection from physical damage only and is not a complete conduit system.
See Chapter 9, Table 1, Note 2
Posted By: skidmark Re: code question - 08/28/03 01:18 AM
According to 312.5(c) it is a code violation. The circuits were being pulled from the basement into the bottom of a flush mounted panel. There were 16 12-2 circuits, 1 10-3 circuit, and 1 6-2 circuit. All of these wires were squeezed into a 4 ft. piece of 2 inch pvc conduit. I don't see how he got them in. Had to use soap! Thanks to all for the input.
P.S. The gentleman had a restricted license good for only 200 amp services. The house has a 600 amp service.
Posted By: Big Jim Re: code question - 08/28/03 05:05 AM
I'm curious. How big does a house have to be to need a 600 amp service? (asks me, crusing by on 125)
Posted By: zapped208 Re: code question - 08/28/03 10:24 AM
Big Jim, I am starting to trim out a house that has a 600 amp service, Its 14,000 sq ft! Also has 25 ton of a/c in it.
Posted By: Tom Re: code question - 08/28/03 03:19 PM
Ron,

312.5(C)(g) doesn't say anything about the conduit being installed as a system. The entire exception expects the conduit to not connect to anything at the top & if thats the case, why bother putting in part g of the exception?

The use of conduit for this type of installation is rarely done for protection, it is for apperance, so I don't think Note 2 to table 1 of chapter 9 applies.

Of course, I've been totally out in left field before.

Anyone else have an opinion on this?
Posted By: George Re: code question - 08/28/03 04:47 PM
Appearance is often the same as protection.

2" conduit will dissipate about 12.1 watts/ft.

16 #12s will produce 18.28 watts/ft.

1 #10 will produce 1.94 watts/ft.

1 #6 will produce 2.66 watts/ft.


It looks bad to me, but I don't know what the breaker size is.
Posted By: WebSparky Re: code question - 08/29/03 12:05 AM
Quote
Ron
Fill derating does not apply if it the conduit is installed for protection from physical damage only and is not a complete conduit system.
See Chapter 9, Table 1, Note 2


The subject here is not about derating.
(bold added by me)

Quote
2002 NEC Handbook comment after Note 2.
The maximum fill requirements do not apply to short sections of conduit or tubing used for the physical protection of conductors and cables. Cables are commonly protected from physical damage by conduit or tubing sleeves sized to enable the cable to be passed through with relative ease without injuring or abrading the protective jacket of the cable. However, a fitting is required on the end(s) of the conduit or tubing to protect the conductors or cables from abrasion. (See 300.15(C).)

Derating is covered here.

Quote
310.15 Ampacities for Conductors Rated 0–2000 Volts.
(B) Tables. Ampacities for conductors rated 0 to 2000 volts shall be as specified in the Allowable Ampacity Table 310.16 through Table 310.19 and Ampacity Table 310.20 through 310.23 as modified by (1) through (6).
(2) Adjustment Factors.
(a) More Than Three Current-Carrying Conductors in a Raceway or Cable. Where the number of current-carrying conductors in a raceway or cable exceeds three, or where single conductors or multiconductor cables are stacked or bundled longer than 600 mm (24 in.) without maintaining spacing and are not installed in raceways, the allowable ampacity of each conductor shall be reduced as shown in Table 310.15(B)(2)(a).



[This message has been edited by WebSparky (edited 08-28-2003).]
Posted By: Reel-Break Re: code question - 08/29/03 03:16 PM
I ran into this a while back.My inspector told me 312.5c Unless the panel was surface mounted and the conduit ran out of the top of it.Forget it can`t have it.I read the artical it clearly states surface mounted and raceway must extend from the top and does not penatrate a structual ceiling.I often used to do services this way but no more.So you cannot run conduit to a flush mounted panelas descibed in this post unless cables are fastened to it via a box under or over panel which would be to much work.
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