ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals
ECN Shout Chat
Shout Box
Recent Posts
220/230/240V 60Hz Systems
by gfretwell. 09/16/18 12:37 PM
Acronis Backup 2017
by gfretwell. 09/16/18 12:46 AM
Inspection camera help
by Bill Addiss. 09/15/18 11:32 AM
Tingle off the water spigot
by Trumpy. 09/15/18 03:24 AM
Lighting Load questions
by HotLine1. 09/14/18 07:04 PM
New in the Gallery:
Plug terminals
Housebilding DIY wiring
Who's Online Now
0 registered members (), 31 guests, and 24 spiders.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate Thread
Page 1 of 3 1 2 3
Pre-twist conductors and tape Receptacles #6241
12/27/01 06:54 PM
12/27/01 06:54 PM
Scott35  Offline
OP
Broom Pusher and
Member
Joined: Oct 2000
Posts: 2,708
Anaheim, CA. USA
Hi Everyone, Got a few quick-ee Q's to throw at 'ya;

At work yesterday, a guy I am working with mentioned that one of the Sparkys in the company is currently inroled in some type of trade schooling. The guy said it was College class for Electrical Engineering, but the descriptions sound more like an NEC code class. That's not relavent, but felt that everyone should know [ [Linked Image] joke].

Anyhow, he mentioned two conflicting things:

<OL TYPE=1>

[*]Pre-Twisting conductors prior to landing a Wirenut is not allowed anymore, due to the increased Resistance, therefore is non-compliant [I know what your thinking, I had the same reaction of [Linked Image]???] and

[*]Taping the sides of Receptacles is non-compliant [got me what this is about [Linked Image]]
</OL>

Is there any validity to these claims per any code or Electrical Engineering studies currently taught???

I'll post this topic in the Holt forum and the IAEI forum [it's been over a year since I have even browsed the IAEI forum! hope I can still get a post in].

Anyone heard of this, or is this just a case of mistaken information [my first and last guess]?

Thanks in advance! [TIA]

Scott SET.


Scott " 35 " Thompson
Just Say NO To Green Eggs And Ham!
Work Gear for Electricians and the Trades
Re: Pre-twist conductors and tape Receptacles #6242
12/27/01 08:04 PM
12/27/01 08:04 PM
R
resqcapt19  Offline
Member
Joined: Nov 2000
Posts: 2,148
IL
The "no pre-twisting" may come from the statement on some wire nut containers that says "pre-twisting not required". It doesn't say that you can't pre-twist them. I can't think of any reason for the no tape rule. With solid wire, I always pre-twist the wires with my Kliens, and if the box is especially tight I have been known to tape up switches and receptacles, of course that was when we could work things hot.
Don(resqcapt19)


Don(resqcapt19)
Re: Pre-twist conductors and tape Receptacles #6243
12/27/01 08:13 PM
12/27/01 08:13 PM
Tom  Offline
Member
Joined: Jan 2001
Posts: 1,044
Shinnston, WV USA
Don is giving away his age(& probably mine) with his comment about taping & working hot.

I'd sure like to see the code citation about not taping receptacles.

As far as twisting is concerned, Don is correct. After all, Buchannon supplies a wire nut driver that is just about gauranteed to twist the wires unless you crank down the clutch on your cordless drill to a very low setting.

Tom

[This message has been edited by Tom (edited 12-27-2001).]


Few things are harder to put up with than the annoyance of a good example.
Re: Pre-twist conductors and tape Receptacles #6244
12/27/01 08:18 PM
12/27/01 08:18 PM
Joe Tedesco  Offline
Member
Joined: Oct 2000
Posts: 2,749
Boston, Massachusetts USA
Recent IAEI meeting, see question 66.

http://rockymountainiaei.netfirms.com/CodeQuest.html

66. An area inspector has turned down installations because the electrician had not twisted the wires before installing spring connectors (wirenuts). Is this a valid position?

No. Section 110-3(b). They are not pre-twisted during UL tests. In fact, pre-twisting can possibly alter the "torquing effect" of the connector’s design. (Incidentally pre-twisting negates the benefit of these connectors. They do not have to be pre-twisted as you would for wrapping with electrical tape.)

Installation Instructions usually found on the smallest unit container (or inside bag) do not state to pre-twist the connectors.


Joe Tedesco, NEC Consultant
Re: Pre-twist conductors and tape Receptacles #6245
12/27/01 08:43 PM
12/27/01 08:43 PM
S
sparky  Offline
Member
Joined: Oct 2000
Posts: 5,360
Chapter,verse,section & or listing requirment should take precedence over personal choice.

Re: Pre-twist conductors and tape Receptacles #6246
12/27/01 08:50 PM
12/27/01 08:50 PM
Scott35  Offline
OP
Broom Pusher and
Member
Joined: Oct 2000
Posts: 2,708
Anaheim, CA. USA
The items that Joe has presented bring light to this discussion.

I mentioned that the Manufacturers do not specify the conductors must be pretwisted, so that would rule out anything on that side [such as the turned down inspection for not twisting the wires].

It's obvious to me that UL would not pretwist, so that gives the Manufacturers "No need to pretwist" angle more validity.

Now, seeing people in the trade use the wirenut twister bit [for cordless drills], or the hand crank twisters - which are produced by the same Manufacturers which make the wirenuts being installed - I wonder if this is acceptable?

Like everyone else, I have been pretwisting conductors [with Linemans' pliers AKA "Kliens"], trim them as needed, then land the wirenut firmly enough to hold as an Insulator to the splice - rather than the sole conductor. This equals out to a tightness which does not distort the wirenut, nor pulls apart from the "Tug Test".

I'll have to print this thread out and present it.

It will be almost impossible to not pretwist after doing so for 18+ years!!!

Now as to the taping of Receptacles thingee, that one just sounds weird!
I would like to see a design or safety issue concerning this!

Scott SET


Scott " 35 " Thompson
Just Say NO To Green Eggs And Ham!
Re: Pre-twist conductors and tape Receptacles #6247
12/27/01 09:15 PM
12/27/01 09:15 PM
Joe Tedesco  Offline
Member
Joined: Oct 2000
Posts: 2,749
Boston, Massachusetts USA
Scott:

I could not find anything in the UL white book that prohibits pre-twisting. I always used my long nose pliers, and lineman pliers and twisted the wires before using a
wirenut.

The use of tape at receptacle, or other device or equipment termination screws is just some additional insurance that one will not get a shock when replacing receptacles, because they forgot to turn off the power!

I was taught by my dad early on to use tape and I still use tape to protect myself!


Joe Tedesco, NEC Consultant
Re: Pre-twist conductors and tape Receptacles #6248
12/28/01 08:01 AM
12/28/01 08:01 AM
electure  Offline

Member
Joined: Dec 2000
Posts: 4,274
Fullerton, CA USA
Like most anything else, the pre-twisting can be done incorrectly.
I've run across a high number of failed connections where the wires were pre-twisted to the point that the diameter of the twisted conductors was large enough that the wirenut couldn't get any purchase on the connection. The wire nut in this case serves no more purpose than that of a piece of tape. Very often the wirenut has fallen off as soon as I touched it.
Also, I've found connections where 1 or more of the conductors has slid back from the rest when twisted and makes poor contact or none at all.
I've never been a "pre-twister", and only know of a couple of connections I've ever had fail.(in 30+ yrs)
My big gripe is with the use of wirenuts out of their listed range. It seems like some people think that they only come in one size...Red. Anything from 2-#18 to 7 or 8-#12 get stuffed in them. (The yahoos that overfill them often wrap them with tape to keep them from falling off). This has been the singlemost often cause of failures I've run into personally, and most commonly have been on neutrals because more of them are tied together in a box on multiwire circuits. (Naturally, because this is the most destructive connection to lose!) [Linked Image]

Re: Pre-twist conductors and tape Receptacles #6249
12/28/01 10:06 AM
12/28/01 10:06 AM
J
JBD  Offline
Member
Joined: Jul 2001
Posts: 599
WI, USA
I have looked at the instructions for wirenuts from: 3M, Buchanan, Gardner-Bender, Thomas & Betts, and Ideal. All of the instructions allow for pre-twisting or no pre-twisting, it appears to be the installer's choice.

The problem with pre-twisting is not the final twist of the conductors. There are two areas of concern, first damage to the conductors done by the jaws of the tool. Second, the loss of contact between some conductors and the spring of the wire nut (for example a #18 ballast lead may be hidden in the twist creases of (2) #12).

Re: Pre-twist conductors and tape Receptacles #6250
12/28/01 04:47 PM
12/28/01 04:47 PM
S
sparky  Offline
Member
Joined: Oct 2000
Posts: 5,360
Quote
I was taught by my dad early on to use tape and I still use tape to protect myself!


I'm with you there Joe. but would add that i've had enough painters & wallpaper guys remove my plates and do things that someone with a shread of respect for electricity would not...

i spil baaad .....



[This message has been edited by sparky (edited 12-28-2001).]

Page 1 of 3 1 2 3

Featured:

2017 Master Electrician Exam Preparation Combos
2017 NEC Electrician
Exam Prep Combos:
Master / Journeyman

 

Member Spotlight
Tom
Tom
Shinnston, WV USA
Posts: 1,044
Joined: January 2001
Show All Member Profiles 
Top Posters(30 Days)
Admin 13
Trumpy 11
sparky 10
Popular Topics(Views)
249,289 Are you busy
187,226 Re: Forum
176,587 Need opinion
Powered by UBB.threads™ PHP Forum Software 7.6.1
(Release build 20180101)
Page Time: 0.024s Queries: 15 (0.003s) Memory: 1.0316 MB (Peak: 1.2078 MB) Zlib enabled. Server Time: 2018-09-19 22:31:07 UTC