To pretwist or not

[jap]

If its Stranded I twist them with my fingers before I put the wire nut on, if its Solid I twist them with my Linemans before I put the wire nut on.

I'm a twister either way.

JAP.

 

[jap]

But on most of my loafs of bread lately I've noticed they twist the twisty counterclockwise so when I go to twist it counterclockwise to open it , it actually just tightens it more and I have to twist it clockwise to get it open.


That's a lot to think about.

 

[George Stolz]

There are few things more malicious a senior engineer at UL can do - than to raise this issue at a lunch table of new engineers. Trust me, it's almost an official 'lunchroom sport' over there!

You see, the wires are NOT twisted for the testing- so the question becomes 'does pre-twisting violate the 'listing and labeling?' Ultimately you reach the same point you do when someone makes a hole in a box: we just don't know.

An alternative approach is to return to the basic concept that all splices will be mechanically and electrically secure. When you pre-twist, it is the twist that accomplishes this, and not the wire nut. The wire nut is simply an insulator at that point - an alternative to yards of tape. The key here is to recognize that the twist is the connection, not the wire nut. The wire nut's ability to hold the wires together becomes academic- all you need is for the thing to stay in place.

Are you failing to take advantage of the full potential of the wire nut? So what if you are? It's a 'suspenders AND a belt' sort of thing.

I disagree. I have seen connections fail where the wires were twisted (bare grounds, actually) and there was no device used to terminate the connection. It amazed me, but a simple plug tester found it.

The wirenut is necessary, it is not just an accessory.

 

[jap]

I've always felt pre-twisting makes the connection tight and the wirenut keeps it tight and the two combined make for a solid connection whereas one without the other not so much.

 

[readydave8]

I disagree. I have seen connections fail where the wires were twisted (bare grounds, actually) and there was no device used to terminate the connection. It amazed me, but a simple plug tester found it.

The wirenut is necessary, it is not just an accessory.

I've seen it too, usually grounds but have also pulled tape off hots and neutrals, found a beautiful spriral, could make circuit work and splice arc by moving splice around or jiggling. (ran across this several times over the years).

 

[Stevareno]

Insert two #12 solid conductors in a wire nut, twist. Reverse twist the wire nut. What do you find? I always find two wires very nicely twisted together.

That may be true for how YOU twist your wirenuts on.
In my experience that is not the case. Very often whoever installed the wirenut stopped when they felt resistance. It makes for a solid connection, but does not actually twist the wires together. This can either be an annoyance or a blessing.

Personally, I pre-twist my connections. It is how I was taught and eliminates the possibility of one of the wires slipping out of the wirenut while you are twisting it on.

 

[don_resqcapt19]

That may be true for how YOU twist your wirenuts on.
In my experience that is not the case. Very often whoever installed the wirenut stopped when they felt resistance. ...

And that is a 110.3(B) violation, with at least one brand, as their instructions specify that you twist until there are two full twists showing below the wirenut.