Stranded wire with device back connections


I'm not a huge fan of the "shove in" back connectors on outlets & switches but they are fast.
Is it ok to use stranded wire (typically I use #12 THHN / THWN) with them?
While I'm asking questions........any tips on preventing "squirt out" when attaching stranded wire to screw terminals?
thanks Bob
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Crimp connectors on them. Harbor Freight has a whole set for $5, or something like that. It is crap, but works a whole lot better than trying to get stranded wire around a screw terminal. (Give up any thought of backstabing right now...)
Of course, you can spend $20 for proper stuff, but that is pretty expensive if you will be just doing a few.
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expensive
Yes, that is big money considering electrical safety is involved and using a cheepo crimp terminal may just give exciting results...
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Bob K 207 wrote:

Pay an extra dollar per device and get heavy duty back-wired devices that clamp the wire in when you tighten the side screws. (I think they can be used with stranded wire up to #10; check the label) Cheap backwired devices will only take #14 solid wire, and I always use the side screws even if I am using 14 gauge wire because I don't trust the spring clips.
I think I have one out in the garage. I'll go see what it says...
Bob
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207) wrote:

No.
Look on the back of the device, and you'll see that it says "solid wire only".

Yeah... don't do that. Use solid wire instead. If you must use stranded, twist the strands together tightly, then tin them lightly with solder before bending a hook onto them to go around the screw. And make sure always to bend the hook in the same direction that the screw tightens (for both solid and stranded wire).
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Doug Miller wrote:

I have in my hand a Leviton "Spec Grade" self-grounding 15A duplex receptical that has both back and side terminals. It looks like it would clamp #12 stranded wire very securely in the back connectors. It doesn't say anything about stranded or solid wire, it just says copper or copper-clad only, and had an AL with a slash thru it.
I also have a Pass and Seymour box from a commercial-grade 20A duplex receptical that only had side terminal screws. The box says it takes copper or copper-clad wires from #10 to #14, and it says "Do NOT tin stranded conductors".
1) These are not 47 devices. They were probably closer to $2.
2) I was kind of surprised by that "do not tin" thing.
Best regards, Bob
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zxcvbob wrote:

Tinned stranded wires are subject to 'cold flow.' The connection will loosen over time.
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No Spam wrote:

And also.....the juncture between the tinned and untinned wire will take very little handling bending before it breaks off right at that point.
If I have to put stranded wire under a binder head screw I usually tin just the very end of the strands so they don't separate and add to the "squirt out" the OP asked about. I bend the hook on the end of the wire so that the soldered end comes back out beyond the screw head and is not clamped by the screw.
IIRC the term "binder head" was originally used to describe the heads of the screws used in these type of applications. I remember them having an shallow rounded groove on the underside of the head to help "bind" the stranded or solid wire in place so that it wouldn't "squirt out". I can't recall looking at any of the screws on curent electrical stuff to see if they are still made that way. (Unintentional pun noted..)
Jeff,
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My name is Jeff Wisnia and I approved this message....

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Do not use stranded on the shove-in/push-in/IDC connections on teh back of outlets. They are for solid wire only.
I perfer not to use them at all, most lite loads may do fine but the connections are not adaquate for heavy loads. I always use the side screw terminals for solid wire.
You can use crimp connectors on stranded wire and install on the side screw terminals.
Again, I prefer to use the outlets used in commercial wiring where stranded is used designed for stranded wiring. They use a square metal plate behind the screw which is designed to clamp the stranded wire behind the plate firmly making a good connection.
MC
(Bob K 207) wrote:

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MC wrote:

Take a look at the "spec grade", or "commercial duty", or "industrial" backwired outlets sometime. They are not shove-ins, they have integral screw clamps.
Bob
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