Taped Wire Nuts

Johnnybob

Senior Member
Location
Colville, WA
I have never taped wirenuts, I don't see the point.

More importantly, why wouldn't you wear suspenders with your tool belt?
To keep your tool belt from dragging your britches down!

And the point of taping wirenuts, in my industry anyway, is that wirenuts in peckerheads on motors can and WILL vibrate lose, and the tape is to hold the conductors together and stationary in respect to each other as much as to hold the wirenut on. Then there is no unequal tension an any one conductor to aid in the vibrations loosening efect.
 

FionaZuppa

Senior Member
Location
AZ
If the connector was going to fall off anyway - the connection likely isn't a very good one, tape won't change that.

You should pull on each conductor after making the connection to ensure it is secured in the joint whether you plan to tape or not.
i have seen many where the coil inside has pulled away from the plastic, but the tape was still holding the cap over the wire. likely due to cheap pos nuts, and you never know what shows up on a jobsite, and what does show up is what is to be used. the tape would provide a little safety if you were digging in the box and the wires were being moved around, etc. and most of the time i bend the wires up into the box to get the advantage of gravity.

as for twisting the wires together, isnt that dictated by the nut maker? many makers instructions do not say to twist wires together 1st.

and those scru-it nuts, doent look right to me, the torque being applied is twisting the wires together for ~4" possibly more. this might mean little force holding the bare ends inside the coil. if you held the wires flat just under the cap and then used a torque style cordless, that would be better.
 
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kwired

Electron manager
Location
NE Nebraska
To keep your tool belt from dragging your britches down!

And the point of taping wirenuts, in my industry anyway, is that wirenuts in peckerheads on motors can and WILL vibrate lose, and the tape is to hold the conductors together and stationary in respect to each other as much as to hold the wirenut on. Then there is no unequal tension an any one conductor to aid in the vibrations loosening efect.
I can't recall any wire nuts ever coming loose in motor boxes, though I probably have seen it a few times and just don't remember, but I also occasionally find one come loose (or more likely was never on right in the first place) in non vibrating locations. Installer error is probably the biggest problem here, I occasionally don't like the condition of a connector and throw it out, the guys that don't get paid as much don't care they just want to get the job done so they can do whatever it is they do when not working. I've had polaris type connectors fail - but the ones I recall failing were ones my help installed and I have no idea if they got them correctly installed in the first place. I seldom have a connection that I made fail without some unusual circumstance contributing to the failure, but being the owner of the business you learn those little things like that cost you down the road if you don't pay attention, your help gets paid by the hour whether it fails or not.

i have seen many where the coil inside has pulled away from the plastic, but the tape was still holding the cap over the wire. likely due to cheap pos nuts, and you never know what shows up on a jobsite, and what does show up is what is to be used. the tape would provide a little safety if you were digging in the box and the wires were being moved around, etc. and most of the time i bend the wires up into the box to get the advantage of gravity.

as for twisting the wires together, isnt that dictated by the nut maker? many makers instructions do not say to twist wires together 1st.

and those scru-it nuts, doent look right to me, the torque being applied is twisting the wires together for ~4" possibly more. this might mean little force holding the bare ends inside the coil. if you held the wires flat just under the cap and then used a torque style cordless, that would be better.
Most modern connector makers don't require pre - twisting, but it is not prohibited either.


After nearly 30 years, I don't like twisting connectors on and my hands especially don't like it if making a lot of connections in a short time. I started using mostly Wago wall nuts (push in connectors) a few years ago, much easier on the hands and haven't had a call back on any of them yet. I do prefer pulling stranded conductor in raceways so I still use twist on connectors for those applications as stranded don't work so well with "wall nuts". They are rated for it if not fine strand but still have issues trying to insert them.
 

FionaZuppa

Senior Member
Location
AZ
Most modern connector makers don't require pre - twisting, but it is not prohibited either.
the instructions i see dont say "prohibited" but do show just stripping wire to proper length and then holding them parallel/even while twisting nut on. under NEC code one must follow manufacturer's instructions. and for clarity, i left out stranded wire.
 

user 100

Senior Member
Location
texas
as for twisting the wires together, isnt that dictated by the nut maker? many makers instructions do not say to twist wires together 1st.
Wire nut manufacturers almost always have pretwisting isn't required printed on the box., not that it is prohibited.

Many will argue that pretwisting is bad with the "either/or" wire nuts b/c the conductors conform w/ the spring better if not twisted first. They have no evidence that a joint is more likely to fail following their hypothesis- if the connector is screwed on tight enough, whether the joint is pretwisted or not, its not going anywhere in a standard installation.

If the wire nuts do have "do not pre twist" printed on the box, is it technically a listing violation if pre twisted? Yes, but a hanging offense and an automatic fire hazard, no, imo.

As for taping nuts b/c the jacket might come loose- I think tape could make things more dangerous by masking a problem- if not for the tape the bare spiral could fault up against a grounded box and ocpd would trip, alerting that there is an issue- better than somebody fumbling w/ tape. Besides that, you aren't supposed to be working hot anyway, and if you do, you can wear gloves/ppe.

But ultimately, whatever specs are laid out and whatever crap wire nuts you are given to use is the way you're gonna roll.:D
 

Johnnybob

Senior Member
Location
Colville, WA
The wire nuts I've seen fail are ones that were installed long before I started here, but they have all been on either material handling equipment, where the motor is mounted on the frame of either a conveyor belt or vibratory conveyor where it's impossible to isolate the motor from the vibration, or high rpm trim saw motors and sometimes on low rpm kiln fans. The kiln fans get tape on the internal phase conductors as well as the motor run conductors due to the high ambient temperature.
 

junkhound

Senior Member
Location
Renton, WA
If one of the nec board's BIL owned a company that made an electric drill and nut drivers, the spec would be :

Use the xyz wire nut holding tool and set the qsr drill torque setting to # indicated in table cvb, etc.. :lol:
 

timo

Member
Location
Phila PA
believe it or not , every box of wire nuts has instructions written on it.I've heard of elevator mechanics using tape on wire nuts because of vibration .
I know cable TV installers do not tape their connectors because of trapping moisture and degrading the connection properties
 

ggunn

PE (Electrical), NABCEP certified
Location
Austin, TX, USA
Occupation
Electrical Engineer - Photovoltaic Systems
believe it or not , every box of wire nuts has instructions written on it.I've heard of elevator mechanics using tape on wire nuts because of vibration .
I know cable TV installers do not tape their connectors because of trapping moisture and degrading the connection properties
Which tells us what we already know: There is no one way to do just about anything that works in all circumstances.
 

flashlight

Senior Member
Location
NY, NY
"If one of the nec board's BIL owned a company that made an electric drill and nut drivers, the spec would be :

Use the xyz wire nut holding tool and set the qsr drill torque setting to # indicated in table cvb, etc.. "

:lol: So true...
 

JFletcher

Senior Member
Location
Williamsburg, VA
believe it or not , every box of wire nuts has instructions written on it.I've heard of elevator mechanics using tape on wire nuts because of vibration .
I know cable TV installers do not tape their connectors because of trapping moisture and degrading the connection properties
CATV connections are highly water resistant with compression fittings installed correctly. I would never tape such a termination because it's unnecessary and a waste of time.
 

Nhrafan

Member
Location
Pa USA
So reading through this I can say I've taped wire nuts as well just cause it was what I was taught. Now seems kinda stupid if they're put on right.
So another question... how do you guys feel about wago push on connectors?? We have them in stock but I've never used them before. They seem like a fast and easy way for multiple wire connections just wondering about reliability or any horror stories lurking about.
 

FionaZuppa

Senior Member
Location
AZ
So reading through this I can say I've taped wire nuts as well just cause it was what I was taught. Now seems kinda stupid if they're put on right.
So another question... how do you guys feel about wago push on connectors?? We have them in stock but I've never used them before. They seem like a fast and easy way for multiple wire connections just wondering about reliability or any horror stories lurking about.
have not heard bad things about the wago connectors.
 
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