They are called wire nuts because....

[chris kennedy]

1

wire

noun, often attributive \?w?(-?)r\ : a thin, flexible thread of metal
: a thread of metal that is covered with plastic, rubber, etc., and used to send or receive electricity or electrical signals
: a small microphone that is worn under clothing in order to secretly record a conversation

They are not called insulation nuts. They are 'listed' pressure connectors. If you capping off a dead end wire, do us all a favor and strip a ?" of the insulation of your conductor THEN install the wire nut.

Knocked out a 1000A 480V main today because someone on my crew in 2006 capped of a wire on the insulation and as I'm pulling said conductor out of the box wire nut fly's off the conductor and how that little coned end welded itself to the box was pure bad luck.

277V to ground short knocked out a 1000A 480V main (Poor coordination ???) to a state facility.

They are wire nuts, not insulation nuts.

End of rant.

 

[kwired]

I believe the name "wire nut" is a trademarked name for a line by Ideal Industries. The name is used by many as the name for any similar design device though. Most people prefer Ideal's "wing nuts" or other's similar design over the genuine "wire nuts" but still call them "wire nuts.

 

[chris kennedy]

I believe the name "wire nut" is a trademarked name for a line by Ideal Industries. The name is used by many as the name for any similar design device though. Most people prefer Ideal's "wing nuts" or other's similar design over the genuine "wire nuts" but still call them "wire nuts.

So are you one of those guys that can't be bothered to strip a little insulation off and install it on the wire?

 

[kwired]

So are you one of those guys that can't be bothered to strip a little insulation off and install it on the wire?

Depends, some seem to grab better then others. 3M Ranger line is my preferred, with Ideal Wingnut probably next.

Some like to lose the insulating cap but spring is still attached to conductor(s) - that situation wouldn't have really changed the outcome in your OP.

Besides you are supposed to turn off the power before working on it:happyyes:

 

[chris kennedy]

Besides you are supposed to turn off the power before working on it:happyyes:

Thought it was.

In addition to the wire nut listed to be installed on the metal part of the conductor where it is meant to grip, sure is handy to have that little bit of exposed conductor to easily hot check to make sure its not energized.

Once the wire nut is applied to the insulation the insulation cones out around the conductor. Nothing better than leaning uncomfortably against a drop ceiling trying to get your tester probe into that little opening.

 

[Nom Deplume]

I like the old 3M Scotchlock wirenuts.
The ones now are both red and yellow.

 

[Jon456]

Yep. I've often pulled dead-end wires out of junction boxes (carefully) and the wire nut on the end falls off because it was just screwed onto the insulation. Sometimes, it seems that only gravity is keeping them onto the upturned end. I always strip the wire back a bit so the threaded insert can grab onto the copper wire.

 

[ActionDave]

So are you one of those guys that can't be bothered to strip a little insulation off and install it on the wire?

I use tape.

 

[J.P.]

I reached cautiously into this mess one day ( on a 8' ladder ) and some wire nuts fell off when I brushed them. Yay.

I was so impressed I took a picture.

This was on the new convention center in town. A big local company did all the work. We got called in later to make a few changes.

Not one single panel, breaker....nothing was labeled in the MDP room. Nothing.

Nothing.

 

[Sparky3141]

Good post. I never thought about it that way. I usually give a quick tug on the wire but I guess I'll start stippin' 'em a bit to be for sure, for sure.

 

[jaylectricity]

Kill the power first?

 

[ActionDave]

Knocked out a 1000A 480V main today because someone on my crew in 2006 capped of a wire on the insulation and as I'm pulling said conductor out of the box wire nut fly's off the conductor and how that little coned end welded itself to the box was pure bad luck.....

Obviously you are ok thankfully.

Took down a main, wow. That must have been a bitch to explain.

 

[hurk27]

They are not called insulation nuts. They are 'listed' pressure connectors. If you capping off a dead end wire, do us all a favor and strip a ?" of the insulation of your conductor THEN install the wire nut.

Knocked out a 1000A 480V main today because someone on my crew in 2006 capped of a wire on the insulation and as I'm pulling said conductor out of the box wire nut fly's off the conductor and how that little coned end welded itself to the box was pure bad luck.

277V to ground short knocked out a 1000A 480V main (Poor coordination ???) to a state facility.

They are wire nuts, not insulation nuts.

End of rant.

Most likely the 1ka service had GFP which would have limited the fault to ground a bit depending upon how high the setting was set, but yep been there and done that, had the same thing happen to a co-worker who was working at our city hall with the fire department in the back half of the building, who opened a junction box over filled with multi-wire circuits and Murphy's law went right into effect as the wire's that could do the most expensive damage on the circuits that fed the most expensive equipment were the only ones that fell apart "the shared neutrals":rant:

Yep $425k worth of the 911 computers and 911 phone systems along with all the 911 dispatch radios, dat recording and control systems all fried from the over voltage that hit them, our company's insurance wasn't too happy, but their investigator did find that some of the liability fell on the city because the work done 15 years pryor was not done to the NEC at the time of the install and the use of dual conversion UPS's would have limited the damage to just the UPS chargers. but it still cost them a bunch, I think they settled on about $200k, still not pocket change, all because they would not let him take the 911 system off line for 20 minutes to run temp circuits to keep the system powered, the judge said that we should have insisted it or waited for a time when they could shut down the system, but even though they had a backup inplace for the county to pick up the 911 calls if a failure of the cities system ever failed anyway they still would not allow it to be shut down because the city would have to pay for the county to pich up the 911 call's after this disaster the county picked up the calls for over two weeks until the equipment was replaced as well as they also installed dual conversion UPS system.

As far as taping them, this was an old carry over from the days that they didn't have the springs in them and so you taped them to keep the vibration of machinery from causing them to loosening up and fall off, but todays wire nuts do not need tape, and in ambient high moisture areas the tape can cause moisture to collect in the connection and cause corrosion and later a failure of the connection, so I never tape, also always twist till you have three turns in the wires just outside of the flange of the nut, this ensures that you have a proper tight connection as long as you had the wires even and parallel when you start putting the wire nut on.

 

[hurk27]

I reached cautiously into this mess one day ( on a 8' ladder ) and some wire nuts fell off when I brushed them. Yay.

I was so impressed I took a picture.

This was on the new convention center in town. A big local company did all the work. We got called in later to make a few changes.

Not one single panel, breaker....nothing was labeled in the MDP room. Nothing.

Nothing.

Well I can see one problem why you had so many loose wire nuts, who ever installed this mess tried to only use red wire nuts which in some cases will not bite into just two wires depending upon the wire size?, this is why when the tan wire nuts came out it made it nice that they were design for a wider wire gauge range and would for the most part replace much of the red and yellow needs, they only connections where you still had to use the reds were 3# 10's and above or the yellows for 2 16's awg or less which the oranges would pick up anyway so I stopped even carrying yellows and just stocked more oranges on the van, but the tan's became my main wire nut i used, and of course they were all wing nuts, if I had allot of connection to make up I broke out the drill adapter which gave my wrist a big break as it would give out if I tried to do too many by hand, trust me you did not have to pre-twist if you used the drill adapter which also made putting short wire together when you run into those jobs where the previous installer cut all the wires short to save space in the outlet box :rant: use a 90? bent nose needle nose pliers to hold the short wires and new tail together and have a nut already loaded into the drill adapter, and just use the drill to put the wire nut on, most manufactures put a drill adapter in all bags of 500 and above.

 

[Besoeker]

I reached cautiously into this mess one day ( on a 8' ladder ) and some wire nuts fell off when I brushed them. Yay.

I was so impressed I took a picture.

This was on the new convention center in town. A big local company did all the work. We got called in later to make a few changes.

Not one single panel, breaker....nothing was labeled in the MDP room. Nothing.

Nothing.

Horrid.......

 

[chris kennedy]

Obviously you are ok thankfully.

Took down a main, wow. That must have been a bitch to explain.

Heck of a flash and was pretty shaky for a bit. Facilities director was cool about it and was telling stories of similar incidents at other facilities.

Now we are trying to find the RFI's sent in 2006 requesting the settings for the main.

 

[K8MHZ]

I don't know of any 'wire nut' listed for only one conductor.

We checked at the supply house one day. Every type they carried had listings for 2 or more conductors. None were listed for one.

 

[kwired]

I don't know of any 'wire nut' listed for only one conductor.

We checked at the supply house one day. Every type they carried had listings for 2 or more conductors. None were listed for one.

They aren't listed for use as blow gun darts either, but that never stopped us from doing so when I was still in trade school.:happyyes:

Yellow Ideal wire nut in a length of 1/2 EMT makes a pretty wicked blow gun with pretty good range. Thread a drywall screw into the open end and through the cap end and you have a dart that will stick into about any surface that is not steel or concrete.

 

[cmaki]

They aren't listed for use as blow gun darts either, but that never stopped us from doing so when I was still in trade school.:happyyes:

Yellow Ideal wire nut in a length of 1/2 EMT makes a pretty wicked blow gun with pretty good range. Thread a drywall screw into the open end and through the cap end and you have a dart that will stick into about any surface that is not steel or concrete.

I've taken an ear plug with a sharpened piece of tungsten from a tig welder in 1/2 EMT. Will almost go through a hollow wood door.

 

[sandsnow]

I don't know of any 'wire nut' listed for only one conductor.

We checked at the supply house one day. Every type they carried had listings for 2 or more conductors. None were listed for one.

Google "ideal wire nut combinations"

Open the pdf from ideal.

you will see 1 #14, 1 #12, etc.