ECN Forum Forums General Topics of the Trade General Discussion Area Q on how best to pre-twist solid conductors

Pre-Twister myself, but from 20 years experience, I have have been on
several calls where loose connections have caused faults, loss of power, wires to come out while trouble shooting in a device box, etc. & all were situations where the wires were NOT pretwisted.
I consider it the same situation as using the "Back Stab" method for installing devices...the continuation of the circuit should not depend on a device.
Pretwist, & cap with a wire nut, & you'll never go wrong!
Quicker yes, but never better.

Do I have to follow the instructions on the wirenut bag in order to maintain the UL listing of the nut? If I use a method that differs from the printed instructions, doesn't that void the items listing? If not, then why not?

It seems that a good percentage of the questions asked on these forums receives an answer resembling "follow the supplied instructions for a proper installation". Why are wirenuts not treated the same?

I always pre-twist solid conductors with a linesman’s. However, since I have yet to find a single wirenut package that describes using the solid-conductor pre-twist method, I just assumed I was voiding the UL listing. Pre-twisting worked so well I didn't care if it was wrong!

So why are wirenuts different than most (every?) other listed device? Why am I allowed to disregard the supplied instructions and make up my own method?

iwire may have already said somewhere, but the instructions don't tell you "do not pretwist". there is a difference between "no pretwisting required" and "no pretwisting allowed"

Here's what I do:

#14- generally I don't pretwist

#12- more than 2 I pretwist

A perfectly good connection can be made with either method. As Bob and others have pointed out, you must follow the manufacturers instructions exactly. They have vigorously tested their product and they know how it should be applied.
That means stripping the wires the right length and twisting the connector until 2 twists become visible, and using the proper wire combinations for which the connector is rated.

If you have a splice spring apart when you take the wire nut off, then the splice was made wrong, plain and simple. I have never had a properly made non-pretwisted splice that I made spring apart afterward. (I've had to take a bunch apart to add or remove wires later on.)

Peter

Jps1006, that is a slippery slope. “If the instructions don’t say you can not do it, then it is fine”. Can you imagine applying that mentality to all listed devices? I didn’t think an electrician was allowed to use any method he or she desired as long as nobody told them not to! If the UL approved instructions only list one method, then who am I to dream up another. Even when the installation instructions state that a certain step “is not necessary” that is not the same as saying the step is acceptable. It may be ok with the UL and it may not be. I didn’t think we where allowed to read between the lines.

Again, I want to make clear that I pre-twist. I just find it odd that all the normal nay-sayers to disregarding/modifying the supplied instructions always change their tune when the wirenut issue is discussed. Perhaps they don’t want to admit they are not totally compliant to UL!



[This message has been edited by triple (edited 05-01-2004).]

You're right, it is getting a little slippery. I personally would not make assumptions that if the instruction are totally silent about a particular step or method in an installation that it was open season for what ever I see fit or however I've been doing it for the last "xx" years. The only reason I would argue that there are lines to read between when it comes to pretwisting is that the instuctions bring it up and use passive language about it. It is a line in the instructions that one needs to stop ask oneself, "what does this mean?"

I too used to be a hardline pretwister, but now I just mostly pretwist. As iwire metioned somewhere else (referencing iwire again. he's got useful stuff) sometimes it is easier to pretwist with a tool than do all that twisting with the nut.

How would one find out exactly what was included in the listing so one wouldn't have to make assumptions?