ECN Forum Forums General Topics of the Trade General Discussion Area Terminating Stranded Wire

Can both of you provide documenatation to your statement?

Don did provide a link to UL, and further info can be found in the UL white book.

I do not happen to have the white book on this computer, but I will try to dig it up later.

My apologies, Don posted between the time I read the posts and when I posted.

The UL whitepages are availble at ul.com go to certification on the left side of the screen or click here

I have always taken the stripper about 2.5 inches from the end of the wire and pushed the insulation off just enough for wrapping the screw. Leave the remaining insulation on. You then can wrap the insulated end back around the recept and the wire never fray's. Connectors are very expensive, especially the good ones. Never been called on it.

As "the kid" stated, twisting the strands counterclockwise prior to termination on device terminal screws will result in the tightening of the screw actually twisting the strands more tightly, as opposed to the untwisting effect that normally would occur.
BTW,

The UL White Book is a valuable investment.

I like the method JValdes mentioned. I never tried twisting it counterclockwise so what great information! Stranded
wire smaller than #8 seems to be a pain to work with. I can't understand why some guys prefer it. I only use it if it is specified or the kid behind the counter gives me the wrong stuff. Can someone list advantages other than flexibility? Just curious.

I don't know that anyone actually prefers it, but think it is it is sometimes better for use in flexible conduits where there is vibration, like at motors, or to take strain off relay terminals.
Sometimes on long conduit runs with tighter bends it can pull easier, but not always.
I do remember reading some theory that stranded wire could carry current more efficiently than solid wire.
It had something to do with eddy currents between the individual strands, but I would have to hunt around on the web to find it again. It may have just been a bunch of balony.

When I terminate stranded around screws, I will go down about 1" and strip it back just enough for the screw. The insulation is not removed from the wire but left of the to prevent the strands from going helter skelter when the screw is tightend down.

I usually use devices that have the pressure plate terminals with stranded wire. If I can't get those, then I crimp spade terminals onto the wires, and put them under the screw heads.

That's what I'll do with the traffic lights if the two-years-older and dumber-than-me guy at the orange box gives me #10 instead of #14. Kinda hard to get the #10 under a terminal block screw w/o taking the screw out and losing it.

Gonna have to try the 'leave the insulation on' trick with the next signal.

Ian A.