ECN Forum Forums General Topics of the Trade General Discussion Area wires in conduit and derate

Taping is good to keep them from curling & nesting. BUT.. cut each band of tape as it enters thepipe.

Redsy,

That sounds like a great idea. I recently saw bundles of 1/2 pvc conduits that were bundled together with a sort of clingy plastic "tape" It was very easy to wrap and unwrap and wouldn't leave any gummy residue, maybe something like that would be even better?

Bill

I don't quite get that Redsy and definitly don't get the following comment from Bill. sorry guys.

Resistor,

Welcome to the Forum!

I think Redsy was talking about taping the wires together to keep them from going wild (crossing, tangling etc.) before they can be pulled into the conduit. And he suggested taking the tape off as right before it enters the conduit.

I was just suggesting something else I'd seen that would keep the wires together and come off easier.

Bill

U guys ever use any 'quick-pull' for this sort of stuff?
http://www.cliffordvt.com/howtopull.html

Resistor,

When pulling multiple smaller stranded wires ,as the length and number of wires increases ,so does the likelihood of forming a rat's nest on the floor.
One way to prevent this is, after a certain number of wires(4, 5, 6?) are laid out, wrap a ring of tape every so often(15,20 or so ft., depending on wire size&length.) You may end up with 2 or more bundles. This really helps, but as the tape approaches the conduit, cut it off so if you have to pull more wires in the future, you won't hook the tape.

Well,yesterday {16 jul} i took these to fine outstanding electricians and seated them at a table and told them to explain why they thought the derating and adjustment was not needed I had the code book with me nearly fell out of my chair when they went to conduit fill table and told me that if I would use this table and never put more wires in it than what it says the fill is then I never had to derate and as long as I never went over 100 ft. I went back to 310 and ask ok what is the purpose of this one shurgged his shoulders and walked away and the other one says that is a hard article to explain and odds are you will never use it if you use the conduit fill tables ,never could get either one of them to explain the purpose of the derating table and the adjustment. I give up on these 2 but did show it to my boss and think he may have done a little calling around THANKS GUYS FOR ur patience with us of less knowledge

Doc,

It sounds like your guys are not too sharp when it comes to the NEC. In the hands-on world derating is something that may not be realized as important, or as a factor at all until there is a failure or a conduit too hot to touch and someone goes looking for an explanation.

Bill

First off, Thanks Bill.

Second, It's been a long time since we did the job I mentioned. Now I understand what ya'll meant, I can't remember if we removed the tape or not, although that would be pretty obvios when you know there is binding.

We did pretty much the same thing Redsy mentioned but we were usng 4" conduit and running around #12 stranded [control wiring](sorry, don't remember the exact type wire) so we taped more than 5 wires in a bundle or we would have had another mess, but taped mess.

I love this site and come here to learn about the codes in reality. My Father was licensed, so I didn't need to be since we worked together. Don't mean to bum you out but my father got lung cancer, and I wasn't going to waist his short time he had, with him trying to tutor me on the NEC.

So now I'll figure it on my own, (in other words I'm workin' on the test) or with help from other sources like this place. So I'm glad this place is here. Thanks for the site!


[This message has been edited by Resistor (edited 07-18-2001).]

Doc,

Those clowns missed out on a free and valuable lesson, but due to their reluctance to care or listen, will never realize how rarely this type of an opprotunity comes around!

My guess is that the only time the derating items will become serious to them is when they see the effects of it on something they installed.

Kind of a basic thing we all have learned in Code classes and in the field - why they can't grasp it is something for a high priced shrink to figure out

Scott SET