Twist 4 No. 12 wires together???

THe trick is to make them long, about 1 inch, twist them up and cut it back to about 1/2". They do make wirenuts bigger than the red one. I see 4 #12s under a red one all the time but I think you want a blue one

Strip them all long. Hold them all together so the end of the insulations line up. Grab the ends with a set of lineman's pliers and twist them together. Snip the ends to the correct length, with a slight taper if necessary. A red wire nut should now work fine.

RE

Joel wrote:

Yep. A blue wirenut is the next size up from red, usually.

Pretwist the wires with lineman's pliers before applying the wirenut.

Bob Weiss N2IXK

Do not exceed the rated capacity of the wire nuts. There are some that will handle four #12. As an option, make a jumper wire a few inches long. Put two wires plus jumper on one wire nut (3 wires total). Put the remaining two wires plus the other end of the jumper on a second wire nut.

Ben Miller

Or even better, use a Wago "Wall Nut" or an Ideal "In Sure" connector. You connect up to six 12 AWG conductors with them. These are far superior to the ancient devices known as "wirenuts". When will we Americans let go of such an ancient technology.

It will happen when the NFPA gets evidence of a body count caused by this or any other wiring method. In the mean time the proposals for the 2008 code will open up next summer. The form is in the back of the NEC or you can get it on the web at the NFPA site

I am not a huge fan of wirenuts because most of my electrical experience is with industrial work where the vibrations are a problem with wirenuts, but for home use they are fine.

In the 3M Wirenut group, the grey wirenut is the next larger one after the red, then the blue. 4 #12 wires should go into a red one OK, but a grey wirenut would easily handle the four.

Do you have a link to either of those devices?

-- Tom H

I looked these things up (Wago "Wall Nut" or an Ideal "In Sure") - wow! So simple and elegant (I've never heard of them before)!!! The only question I have: aren't these connectors more bulky than wire nuts? Sometimes there is not too much room in the box...

The company that I work for used them on a trial basis (two boxes of 5000 count, yellows) on a fairly large commercial job last summer (lighting only). As far as ease and quickness of installation, they are _definitely_ the monkey's nut. As far as bulkiness, the "In Sure" connectors allow one to fold the wires into the box much easier than when using a regular wirenut because the connector allows the wires to twist as they are folded into the box. The question is, when is the price going to be competitive with wirenuts? Of course, only time will tell if the "In Sure" or similar connectors provide dependable connections (over a number of years, not just the warranty period.)

Isn't this the same technology used in the much maligned "back stabbing" wiring devices? It doesn't look more secure than a wirenut, just faster.

Interesting gadgets. What makes the electrical connection? Is it a knife edge that digs into the wire? What is the electrical resistance per contact? Although wire nuts are difficult to use sometimes, the twisting of the wires together with the conductor within wire nut make for multiple connections. Although I haven't measured the resistance, intuitively I think it would be lower. Comments?

Al

I tend to agree, although I don't have any hard data. The real test is not initial resistance, but deterioration due to atmospheric exposure, thermal cycling, oxidation, etc. over time. This is what got aluminum wire into trouble. Wire nuts may not be the ultimate, but the name brand ones, when properly applied, generally tend to do quite well in this regard.

Ben Miller

I read the thread and noticed something and had to ask-

Being as how I had tested some of the first wire-nuts for approval for the military (back when they were introduced and before they were widely used in residential and commercial work) I was interested in knowing why most posters recommended twisting the wires before they put on the wire nut.

Basically, I wondered where they got that information? Not that it isn't proper practice nowadays to use that process with the various types of wire nut designs and all would pass UL. I ask out of curiosity because in our tests by twisting first and then applying the nut, back then about half failed the capacity test, while laying straight wires and turning them with the nut had no failures. In fact, the instructions were quite specific about NOT twisting first.

Theory (verified by inspection of a proper sample size) was that the truncated cone shape of the screw would create a lot of pressure on the wires and that pressure was used with the mechanical smearing of the crossing wires so as to flatten and "weld" the copper. If the wires were twisted first, the pressure couldn't smear the circumference of the wires-in-contact in order to broaden the surface-in-contact. They would just be captured. The twisting was merely a side effect of the mechanical-smearing-under-pressure mechanism, and not necessarily something desirable in itself

In other words, all that the pre-twisted wires ever did were lay under a greater pressure than without the nut (with a little smearing at the ends) while the parallel wires twisted by the nut saw the very high pressure from the screw- effect "going up the bundle" and they smeared to a larger contact surface area and welded all along the wires under the nut rather than just the tip - the weld went up the bundle until the pressure from the force from the turning was below that needed to smear and weld the metal . (We turned some just a bit, and then backed off the nut and checked. Did it again and again with several numbers of turns to verify the welding)

Because a cylindrical pair-triangle-quadrangle was put into a cone, there was nearly point contact along the narrow ring where they met and thus very high pressure. So as the bundle was smeared along the cone and forced into the cone shape alnong the outside, the wires in contact were being squeezed onto each other as they were turned across their long axis by the twisting of the long axis, in effect welding the soft copper in contact to a depth into the wire proportional to the pressure at that area. The screw didn't just apply its pressure all along the wire bundle at once, but the pressure moved up the bundle as the twist just ahead of the nut twisting-under-the-nut-pressure-area turned the wires at the point of max force. You ended up with maximum deformation of the copper and thus maximum surface area in contact The spring-core type gave a wider range of deflection with the same pressure as the screw types, but less pressure.

So I assume UL has changed their requirement (from the old informal approval process?) that wire nuts had to be applied to parallel wires to meet the requirement.

Anyone familair with the approved source of the "twist -first" method, and/or what UL requires as to approved application, and what UL used in their formal testing procedure - twisted or parallel?

just curious

I find your information fascinating and I am sure that it is sound. I too, would like to read the answer.

I have done both....twisted and not twisted. I can tell you tho, that twisting is taught as "the" way to apprentices in the trade. This even applies to stranded wire where twisting has virtually no value unless you are cramming more conductors into the wire nut than it is rated for. Some practices are really, really hard to change.

I have even heard threats of dismissal for anyone caught 'not' twisting their splices together.

I think the twisting thing just comes from the idea that it is easier to do on a ladder and you know all the wires are really in the nut. The reality is both will work fine if done well. The old style hard wirenut still maintains the taper but the newer soft ones will actually end up with the splice completely wrapped in the spring. I cut a few apart last night to see what happens inside a wirenut.

Wow, that is very interesting. I always thought that the wire nut was just a cap used for insulation. I always twisted the wires with a plier and then trimmed them before I applied the wire nut. I depend on the twisting of the wires for the connection. As far as I know, I haven't had a failure. If I remember correctly, the wire nuts I used in the 50's didn't even have a spiral wire insert.

Al