I got an attic fan and the wires to the motor are puny stranded wire.  I'm hooking them up to 12 AWG Romex (NM).  I don't feel all that good about wire nuts on them.  There is a junction box on the motor, but not a way to clamp the wires down and don't want them vibrating loose.   I'm wondering about two options

1. Wago Wall nuts -- I have the ones push-in ones not the lever nut.   

 

Are there different sizes so that both wires would not make good connection?



2. Using crimp on insulated connectors.    I have red, blue, and yellow and don't know which color(s) fit what size wires.  Preference to spade or round pin connector?
 

 

 

Edited June 6, 20196 yr by kmealy

For the insulated crimp type connectors,  color code Yellow 10-12,  Blue 14-16,  Red 18-22.     I would just use the Wegos, those are normally 12-16 or 18  I doubt if the wire is less than 18 ga.   Attempt to pull out the wires from the Wegos, that will tell you if they are connected correctly.    If using the spade or round pin you will need the mating sides for different size wire, make sure they will fit together.   Roly 

I hate crimps. I’ve always used wire nuts for this type of connection and never had a problem. Reverse wrap the nut/wire with electrical tape can help keep the nut from loosening 

Another solution, one we use in automotive and I use when doing project work using stranded wire.  Solder the end of the stranded wire.  Now you have SOLID wire then use a wire nut.  If you use those connectors, same thing.  Solder the wire, then insert into the connector and heat it up.  Makes a strong connection.  I remove the plastic cover and then use shrink wrap over the end to insulate / cover as much as possible.

I’ve never had an issue with splicing solid and stranded wires together, yes they can pull apart easier, but that’s mostly because of the wires not being fed into the wirenut, evenly. Gotta check on the push in connectors, and make sure they are rated for stranded wires, I believe the initial ones were rated for solid wire only. The junction box on the motor has no round knock out/opening that a connector can be used on? Photos? Wouldn’t reverse wrapping tape put pressure on the wirenut to unwind? Maybe I’m not following that one correctly? One can also solder the splice together, creating a mechanical splice, as well as an electrical splice. All motors I’ve ever wired were stranded wires, and all the ones fed with Romex/BX/armored cable have a stranded/solid wire mix. All motors are gonna have a vibration that most splices never see, but wirenuts with tape have always been up to the task for me, just my $.02.

I am in the wirenut camp on this one.

7 hours ago, Artie said:

Wouldn’t reverse wrapping tape put pressure on the wirenut to unwind? Maybe I’m not following that one correctly?

Maybe I used the wrong term there. What I meant was wrap the tape so that if the nut tries to loosen it will tighten the tape wrap.

Wirenuts are made so that the left hand holds the wires together and the right hand holds the wirenut and installs it by rotating it clockwise (looking at the back of your right hand). At the voke school I attended, one of the kids was left handed, took him two years to learn how to make splices with his right hand so the wirenuts would actually go on. Yes Lew, you are correct, you would wrap the tape in the same direction that you screwed the wirenut on, so it would help hold the wirenut on.

1 hour ago, Artie said:

At the voke school I attended, one of the kids was left handed, took him two years to learn how to make splices with his right hand so the wirenuts would actually go on.

 

Same things with screws.  They are made with a right hand thread because the right hand wrist naturally twists and has more power in that direction but then left handed people better at unscrewing them.

7 hours ago, HandyDan said:

They are made with a right hand thread because the right hand wrist naturally twists and has more power in that direction but then left handed people better at unscrewing them.

My screw gun is ambidextrous.  

12 hours ago, Woodbutcherbynight said:

My screw gun is ambidextrous.  

Well, heck. Gotta get me one of them. 

Did some more looking when the sun was out.   The stranded wire is 18 AWG and the Romex is 12.   

 

For years, I always heard "righty tighty; lefty loosie"    Never made sense to me because it all depends on how you look at it (edge away or edge close, front or back side, etc.)    Then I learned the "right-hand rule."    Point your right thumb the way you want the thing (nut, bolt, screw, etc.) to go.   Then making a fist, your fingers point the rotation you want to go.

 

What about left hand threads then ?  roly

2 hours ago, kmealy said:

Did some more looking when the sun was out.   The stranded wire is 18 AWG and the Romex is 12.   

 

Gets asked by the first year students every year. The motor only needs a wire rated for it’s load. Your house circuitry will NOT be less than a #14 for 120 volts or higher. A standard yellow wirenut should make a secure splice with that a #12. I would strip the stranded wires back a little more, so they will wrap around the #12 wire, as the wirenut is being twisted.

1 hour ago, Roly said:

What about left hand threads then ?  roly

Use the "left hand rule"

 

upon further investigation, there is a circular knockout on the junction box.   Got the wire clamp in now.

As some have said I always "tin" or solder stranded together to become solid with good soldering practice and pure electrical solder not that plumbing solder.  Then the strands in the wire stay together and twist clockwise (when looking at the top of the wire nut) I am a lefty but I just envision a clock and go that way except for Left hand threads for those your CCW.