Page 1 of 4 123 ... LastLast
Results 1 to 10 of 38

Thread: Stranded wire on receptacles

  1. #1
    Join Date
    Jun 2003
    Posts
    5,617

    Stranded wire on receptacles

    This goes back to another thread that's a few days old, but I keep wondering about this. (Bob, I hope you don't mind me quoting you from another thread.)

    Quote Originally Posted by iwire View Post
    The NEC allows either stranded or solid and all 15,20 & 30 amp devices are listed for both stranded and solid.
    I'm not sure I understand what you are saying. Does that mean stranded wire can be wrapped around the screw terminal on a standard receptacle?

    I thought some type of spade lug was required to keep the strands from coming out from under the screw as its tightened. Or is that completely wrong?

    Steve

  2. #2
    Join Date
    Dec 2006
    Location
    Chapel Hill, NC
    Posts
    25,982
    As someone pointed out not all devices will accept stranded but if they can then yes you can wrap the standed wire around the terminal of the device. A good trick is to strip the wire but don't remove the jacket until you wrap the wire around the screw. The jacket at the end of the wire will hold the strands together as you tighten the screw. Personally I don't like connecting stranded wire to devices unless they have a back stab that tightens with the screw , as in some Hubbell devices.

  3. #3
    Join Date
    Jan 2009
    Location
    Easton, Maryland NEC: 2011
    Posts
    7,549
    Twist the strands CCW and they will not splay out, but cinch tight.
    "Electricity is really just organized lightning." George Carlin


    Derék

  4. #4
    Join Date
    Feb 2003
    Location
    Ohio
    Posts
    989
    Quote Originally Posted by jumper View Post
    Twist the strands CCW and they will not splay out, but cinch tight.


    Pete
    Experience is something thats gained shortly after you really needed it.

  5. #5
    Join Date
    Feb 2003
    Location
    Illinois
    Posts
    19,090
    The following is from the UL Guide Information for Receptacles for Plugs and Attachment Plugs (RTRT).
    Terminals of the wire-binding screw, setscrew, or screw-actuated back-wired clamping types are suitable for use with both solid and stranded building wires.
    Last edited by don_resqcapt19; 11-18-11 at 10:58 AM.
    Don, Illinois
    "It is the first responsibility of every citizen to question authority." B Franklin

  6. #6
    Join Date
    Feb 2003
    Location
    NE Arkansas
    Posts
    2,222
    This is one area where UL and I have a difference of opinion. As far as I'm concerned, the lab geeks and engineering wonks have been sniffing too much solder on this one ...

    IMO ... no matter what tricks you use, the screw heads of devices are terrible attachment points for stranded wire. "Back stabs" are not suitable for stranded wire at all. Only some form of clamp/pressure plate, one that helps contain the wire (rather than squeeze it out) is any good at all. Final result: the 'approved' methods don't do so well.

    UL will tell you that no devices have been evaluated for use with any spade, fork, or ring terminals. Technically, that's true; it's not mentioned in their standard. There's also the practical matter that darn few such fittings will actually fit on the devices without something being modified. Still, I bet I could visit UL's own labs today and find numerous places where their own techs have used this method in the assembly of their test equipment. Final result: the 'unknown' method can work really well.

    IMO, this is one time you want to forget 'code minimum' and actively select devices with better ways to land the wires.

  7. #7
    Join Date
    Mar 2008
    Location
    Michigan. It's a beautiful penninsula, I've looked around.
    Posts
    5,782
    Quote Originally Posted by renosteinke View Post
    This is one area where UL and I have a difference of opinion. As far as I'm concerned, the lab geeks and engineering wonks have been sniffing too much solder on this one ...

    IMO ... no matter what tricks you use, the screw heads of devices are terrible attachment points for stranded wire. "Back stabs" are not suitable for stranded wire at all. Only some form of clamp/pressure plate, one that helps contain the wire (rather than squeeze it out) is any good at all. Final result: the 'approved' methods don't do so well.

    UL will tell you that no devices have been evaluated for use with any spade, fork, or ring terminals. Technically, that's true; it's not mentioned in their standard. There's also the practical matter that darn few such fittings will actually fit on the devices without something being modified. Still, I bet I could visit UL's own labs today and find numerous places where their own techs have used this method in the assembly of their test equipment. Final result: the 'unknown' method can work really well.

    IMO, this is one time you want to forget 'code minimum' and actively select devices with better ways to land the wires.
    I found that pig tailing the device with solid wire and then using a wire nut to connect the stranded and the solid together to be a decent option. I rarely see stranded wire under a plain screw terminal that looks like it's a good connection.
    Cheers and Stay Safe,

    Marky the Sparky

  8. #8
    Join Date
    Feb 2003
    Location
    Massachusetts
    Posts
    48,482
    Quote Originally Posted by steve66 View Post
    This goes back to another thread that's a few days old, but I keep wondering about this. (Bob, I hope you don't mind me quoting you from another thread.)



    I'm not sure I understand what you are saying. Does that mean stranded wire can be wrapped around the screw terminal on a standard receptacle?
    Yes.

    Quote Originally Posted by Dennis Alwon View Post
    As someone pointed out not all devices will accept stranded
    Can you point out any 15, 20 or 30 amp devices that will not accept stranded?

  9. #9
    Join Date
    Jan 2009
    Location
    Easton, Maryland NEC: 2011
    Posts
    7,549
    Quote Originally Posted by K8MHZ View Post
    I rarely see stranded wire under a plain screw terminal that looks like it's a good connection.
    That's 'cause most people screw it up. It is pretty easy after you do it enough. Try the CCW twist, it works well.
    "Electricity is really just organized lightning." George Carlin


    Derék

  10. #10
    Join Date
    Mar 2008
    Location
    Michigan. It's a beautiful penninsula, I've looked around.
    Posts
    5,782
    Quote Originally Posted by jumper View Post
    That's 'cause most people screw it up. It is pretty easy after you do it enough. Try the CCW twist, it works well.
    Why not just use the other end of the pigtail?

    If one end is clockwise, the other end has to be counter clockwise, doesn't it?

    Edit....nevermind, I guess not....but that brings me to the question of why stranded wire isn't already CCW?
    Last edited by K8MHZ; 11-18-11 at 02:25 PM.
    Cheers and Stay Safe,

    Marky the Sparky

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •