ECN Forum Forums Code Related Discussion NEC & other Code issues 100 A feeders

This has been beat to death in Mike Holt's BB and the DIY BB, but I'm still confused.

My supplier only carries #4/0 and #2 Al SE and SER cables... no other sizes. I realize that the supplier is not infallible...

Bidding around here is hard enough, I can't compete with the ignorant! Just what the heck am I supposed to do with 100A Sub panels? #3 CU THHN in pipe? #3-3 w/G Cu NMB cable (which is unavailable here)? The supplier is clueless, I just called him...

I've been through about $10K of lost bids this week mainly due to sticker shock...

Any venture capitalists out there? I promise not to spend frivolously like the tech companies did...

If not...Anybody wanna buy a slightly used Electrical Business? Just Kidding folks...




[This message has been edited by sparky66wv (edited 05-16-2001).]

What wiring methods have you used in the past to install subpanels? You could order what you want to use and keep it in shop stock.

Oh... This is in reference to Table 310-15(b)(6),

100A feed through discos are unavailable here, we generally use load centers for discos (raintite). Does the feeder from the first load center (being used as a disco) to the second (being used as the main panel) qualify as a service feeder, or is it a sub feed??

BTW the EI passed a similar install just a few weeks ago... It was fed from a 200A panel with #2 SER (most around here would have used SE) and was obviously a sub panel.

Would using a main breaker in the sub panel instead of a MLO make any difference in the definition of the intended use of the cable?

This code loop could triple the price of a sub panel install for me and put me out of the competition, I can't be the only one complying with codes that "no one has heard of" around here... and expect to make money, or even get the jobs in the first place!

There appears to be some controversy on whether or not #2 SER is allowed in a sub feed... Sorry I didn't make that part clear...
http://www.mikeholt.com/forum/Forum1/HTML/000545.html
http://forum.doityourself.com/showthread.php?threadid=58652



[This message has been edited by sparky66wv (edited 05-16-2001).]

oh boy,
here we go...someone call for more tankers...

personally, i'm confused as to which code overrides which, and what changes have taken place ( or are going to..)

some articles to consider;
T310-15(b)(6) and whatever the 99' change was
338-4(a) brings you to;
336 A&B ends up in
336-26 , note the 60 deg deal...
110-14(c) honorable mention.....
T-310-16 why not....

Whoa... looks like that leaves us with a #1/0 Al Sub Feeder for 100A...

Steve or Bill... you got the ROP's on this?



[This message has been edited by sparky66wv (edited 05-16-2001).]

it would be at;
http://www.nfpa.org/Codes/National_Electrical_CodeR_NEC/Proposals/necpdf/A280-310.PDF

go down to about pg 65 ( Adobe Acrobat file)

points of interest;
Log 3908(accept) - to exempt 336-26 in T310-15(b)(6)
Log4200(reject) substantiation states;
[ "99' wording schizophrenic" ]
i sense the CMP's intent here, and a little frustration.....
Log 2895(reject) looks like a table for ampacity?>>>....

Just what the heck am I supposed to do with 100A Sub panels? #3 CU THHN in pipe?


That's what we typically do. MLO sub-panel unless the sub is in a separate building.

I don't follow the other concerns, questions that lead to the 1/0 AL. We don't use AL for sub panels unless we are going underground.

GJ


[This message has been edited by golf junkie (edited 05-16-2001).]

GJ;
the article in question is not entirely clear as to where #2 for 100A ,4/0 for 200A can be run in a dwelling.

the code had a 99' change, and is apparently going to have a change or two in 02'.

I'm confused on what has changed and why...

Another point, probably only a WV thing, but how am I supposed to pipe in and use 3 #3 THHN copper for the feeders AND a reduced ground and compete with those using only a #2 Al SE (NOT SER)?!??! Please realize that there is a major cost difference here...And please find me a loophole! (I'll use SER though...)

BTW I've lost 3 of 3 bids the past week, 2 due to "unfair" competition like I mentioned above... the third due to "Sticker shock"...
I don't mind it so bad when I actually bid against electricians...