Return to the Electrical Wiring Forum | Post a Follow-Up

 o
Push-in Wire Connectors Stranded Wire Soldering

Posted by bltglt (My Page) on
Wed, Jul 28, 10 at 2:12

Hi, I am an average homeowner with basic knowledge of home wiring. I've done some of the wiring in my house and have been doing basic home wiring for at least 4-5 years. My question is concerning the Push-in wire connectors and stranded wire. I've always found the wire nuts to be difficult to handle and the whole debate about pre-twisting or non pre-twisting to be mind boggling. I can make a good connection using the wire nuts, but I prefer to use the push-in connectors. I trust them more, and I've had great success with those using solid wire (14awg and 12awg). These connectors are rated for stranded wire (20awg - 14awg), but every time I insert a stranded wire only a few strands go under the locking mechanism. I've tried spinning the stranded wires clockwise with my fingers to stiffen the wire, but the wires still spread when I insert them into the push-in connector. The rest do touch the metal part of the connector by building up in the shape of a ball. However, I have been looking for a better way to do this. I tested out a soldering technique where I used my Weller 40w station to heat the wire up and apply a small amount of Rosin Core solder (60/40) to the very tip of the stranded wire. This seems to hold the strands together so that the wire goes into the push-in connector just like a regular solid wire. My question is, is it o.k. to apply solder to the tip of the stranded wire to hold it together? What does the electrical code say about this? Also, is it o.k. to use this some technique with wire nuts?


Follow-Up Postings:

 o
RE: Push-in Wire Connectors Stranded Wire Soldering

I don't know of an application where 'tinning' of the stranded wires is not acceptable, or even preferable.
The balling up of the stranded wires as you describe is never acceptable.


 o
RE: Push-in Wire Connectors Stranded Wire Soldering

Are the push-ins actually listed for smaller sizes of stranded wire?


 o
RE: Push-in Wire Connectors Stranded Wire Soldering

Thanks for your replys. Yes, the push-ins are rated for stranded wire. Let me list on here all the types of wires that are compatible with it: #18-#12 AWG Solid, #18-#14 AWG Stranded, #18-#12 AWG Tin Bonded Stranded. I assume that Tin Bonded stranded is not the same as a solder-tinned wire because this device can only handle regular stranded gauge wire up to 14 AWG with 12 AWG being too big, especially with solder melted over it. Here's another question, is it o.k. to apply a small amount of solder to the tip of spinned stranded wire that comes on AFCI breakers?


 o
RE: Push-in Wire Connectors Stranded Wire Soldering

I have some doubts about overall tinning of stranded conductors. Solder is meant to seal and reinforce a connection that's already mechanically solid. It's not as good a conductor as copper.

However, I don't see anything wrong with tinning just the last 1/8" or so of a stripped end to help keep the strands together. In fact I've seen that done on zip cord used in factory-made table lamps.

When connecting stranded wwire to a screw terminal, try twisting the strands counterclockwise instead of clockwise. It helps keep them together while you tighten the screw.


 o
RE: Push-in Wire Connectors Stranded Wire Soldering

" Yes, the push-ins are rated for stranded wire. "

I see a lot of restrictions on stranded wire.

The number of wires making up the strand, the size of the strands, etc.

I saw at least one that allowed only 7 strand #18.

I have a pieces of 4/0 in my office that has thousands of strands (they are around #38).
It is as limp as a noodle.

It is designed for places that require movement of the wire over a joint.

The only connections it can be used with are fully enclosed screw lugs with a pressure pad bearing on the wire.

At least the visibility in many of the push in connectors allows you to see if strands cam out of the bundle.


 o
RE: Push-in Wire Connectors Stranded Wire Soldering

My under cabinet lighting is stranded and didn't want to work with the connectors so I tinned the wires. It worked great after that but the current draw is very low.


 o
RE: Push-in Wire Connectors Stranded Wire Soldering

"My under cabinet lighting is stranded and didn't want to work with the connectors so I tinned the wires. It worked great after that but the current draw is very low."

I hope that is line voltage (120 V) lighting and not low voltage.


 o
RE: Push-in Wire Connectors Stranded Wire Soldering

Whilst it would appear at times tinning is acceptable (some wires in appliances come pre-tinned at the ends) I don't think it's wise. I have found the connections tend to gain resistance which generates heat, which generates resistance.

Use the twist marettes or an approved crimping connector.


 o
RE: Push-in Wire Connectors Stranded Wire Soldering

Yes Brick 120v puck lights. I do not think there is enough current to cause a problem in this instance.


 o
RE: Push-in Wire Connectors Stranded Wire Soldering

"I have found the connections tend to gain resistance which generates heat, which generates resistance. "

Only if you make a bad solder joint.


 o
RE: Push-in Wire Connectors Stranded Wire Soldering

To the OP: You say that you've had "great success" using pushin connectors and that "you trust them more".

You *REALLY* *SHOULD* *NOT*!

Pushin connectors are, IMHO, sent to us straight from hell. I *never* use pushins and when I'm working on an outlet or switch that uses them, I remove it, throw it away, and install a better one that uses screws.

The reason is that your pushin connectors just don't have the necessary surface area to properly handle a decent amount of current. They are quick and easy to use, but "quick" is way too often a sacrifice of "reliable".

The little tiny barb that hooks and grabs the wire has nowhere near the surface area of a screw or a compression plate. It might be fine for an amp or 2, but when you start to actually try to carry 15 amps through a 15amp outlet, those little connections start to heat up.

Screws are a pain, buy there is a decent compromise available. Buy pro-grade "rear entry" outlets and switches. They have a hole in the back like a pushin, but instead of a spring loaded clip, the straight piece of wire is sandwiched between 2 brass-plated steel plates and then when you turn the screw on the side of the outlet, the 2 plates squeeze tightly onto the wire over it's full length. You can put a decent amount of force on the screw which will tend to flaten the copper wire, which provides for more surface area and a very low-resistance contact.


 o
RE: Push-in Wire Connectors Stranded Wire Soldering

Rookie registered today to answer questions asked almost 3 years ago.
That aside, the advice given above is OK.


 o
RE: Push-in Wire Connectors Stranded Wire Soldering

The op is talking about push in wire connectors (wagos) not back stab receptacles. There is a big difference in the application.


 o
RE: Push-in Wire Connectors Stranded Wire Soldering

It appears this original post was about the push-in connectors that can be used instead of wire nuts.

This reply - 3 years late - is somebody talking about problems using backstab receptacles & switches - which we already know all about.

Obviously, they did not read, or understand, the original poster's message.


 o
RE: Push-in Wire Connectors Stranded Wire Soldering

Wow, btharmy, 6 minutes apart - but same conclusion. I think you can probably type faster than me!


 o Post a Follow-Up

Please Note: Only registered members are able to post messages to this forum.

    If you are a member, please log in.

    If you aren't yet a member, join now!


Return to the Electrical Wiring Forum

Information about Posting

  • You must be logged in to post a message. Once you are logged in, a posting window will appear at the bottom of the messages. If you are not a member, please register for an account.
  • Please review our Rules of Play before posting.
  • Posting is a two-step process. Once you have composed your message, you will be taken to the preview page. You will then have a chance to review your post, make changes and upload photos.
  • After posting your message, you may need to refresh the forum page in order to see it.
  • Before posting copyrighted material, please read about Copyright and Fair Use.
  • We have a strict no-advertising policy!
  • If you would like to practice posting or uploading photos, please visit our Test forum.
  • If you need assistance, please Contact Us and we will be happy to help.


Learn more about in-text links on this page here