Twisting the wires with linesman pliers before using a wire nut?

Dennis Alwon

Moderator
Staff member
Location
Chapel Hill, NC
Occupation
Electrical Contractor
This is from page 3 of our FAQ's https://forums.mikeholt.com/threads/2020-nec-faqs.2551625/

  • Is pretwisting conductors required when using wirenuts?

This question is not answered in the NEC, it is a product listing question. Products are required to be used in accordance with their listing by 110.3(B).

Most (if not all) wirenuts are listed for use as follows: Pretwisting the conductors is not necessary, but not prohibited - as long as the conductors are twisted once the wirenut is in place, then the manufacturer's instructions have been followed and the code is satisfied. If the connection is not twisted, then there is a 110.3(B) violation when using most (if not all) brands of wirenuts.

That said, most electricians will agree that a pretwisted connection is the most professional method, as it allows the installer to see without a doubt that the connection is tight before installing the wirenut.

But pre-twisters and post-twisters are all welcome here.
 

RichB

Senior Member
Location
Tacoma, Wa
Occupation
Electrician/Electrical Inspector
We had ideal come in years ago and do some training and this was included--at the time they said no need and it could actually damage the conductors by over twisting them--like when you over twist tie wire and it breaks was the example he used

I quit pre twisting then even though I have never seen nor heard of that happening--Personal choice
 
It's like wiring a house with all 10 guage. Is it better?
To me, it doesn't matter what the joint is like with the wire-nut removed.

You could say the same thing about split-bolt joints.
I am inclined to agree, but the two issues I have with nut twisting are:

1. It's easy to not wire-nut-twist enough. I see that a lot. Granted that is sort of installer error, but twisting with linesman's seems more "black and white" to me.

2. Similar to #1, The inspection issue. Sometimes one conductor doesn't get grabbed by the nut and gets pushed out. And you can't tell.
 

James L

Senior Member
Location
Kansas Cty, Mo, USA
Occupation
Electrician
.... the two issues I have with nut twisting are:

1. It's easy to not wire-nut-twist enough. I see that a lot. Granted that is sort of installer error, but twisting with linesman's seems more "black and white" to me.
lazy, not easy.

2. Similar to #1, The inspection issue. Sometimes one conductor doesn't get grabbed by the nut and gets pushed out. And you can't tell.
that's user error. If none of the conductors are leading or trailing, a wire nut grabs all of them that it's rated for
 

LarryFine

Master Electrician Electric Contractor Richmond VA
Location
Henrico County, VA
Occupation
Electrical Contractor
1. As with anything else, yes. Wire-nuts are pressure-contact connector devices. It's incumbent upon the installer to make sure adequate contact pressure is attained.

2. Again, agreed. I use consistent stripping and finger pressure to make sure the wires remain in position, and always pay extra attention to solid/stranded combining.

With each and every connection I make, I focus on what I'm doing with the intent that this connection will not be the one that fails.
 
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