Need small "wire-to-wire" connection scheme

Discussion in 'Electronics Resources' started by ue418, Apr 30, 2011.

  1. ue418

    Thread Starter New Member

    Jun 22, 2010
    I need a way to connect four tiny wires (30 AWG) from a load cell to four larger wires. The "beam-style" load cell rotates with a steel "follower", and its tiny wires should ideally be kept motionless relative to the load cell/follower. That sort of implies that whatever plug/receptacle combination I end up with should be affixed to the follower. So I'm still searching desperately for a quick and easy way to do this, that looks clean and professional. I should say that the distance from the loadcell (where the tiny wires come out) to "Point B" (a terminal strip) is about 6 inches, mostly in the vertical direction.

    My best solution so far is to make a little circuit board, solder a 4-position (2.54 mm pitch) terminal strip to it. And also solder a "vertical" USB-receptacle, which is for "through hole" mounting also. Of course, each pole of the terminal strip is connected to one of the four contacts of the USB receptacle, via traces in the tiny board. And I would then mount this board to the top of my follower. Then I will simply cut off 5 inches of a type-A USB cable, de-sheath and strip the other end (which simply go to the terminal strip at "Point B"), and plug the connector into my soldered USB-receptacle. And the four tiny wires from the load cell go into the soldered terminal strip. But this seems like a bit of work, and I'm concerned about the mechanical integrity of that USB receptacle. And the board will simply be cut by me, from an appropriate Radio Shack single-sided board. And the mounting of said board, to my follower, may not look very professional either (there is not much room there).

    So, if I could find a tiny/light IDC (insulation displacement) type of connector arrangement, that will accept 30 AWG wire on one end, then I may not have to secure anything to the follower at all. As long as the plug/receptacle combination is very small and light, there will be little stress on the tiny wires, where they connect to my load cell.

    So to summarize, I think I need an IDC type of plug/receptacle, wherein the plug receives four tiny 30 AWG wires, and the receptacle receives four 26 AWG wires (or vice versa). I don't really care whether the 30 AWG wires come into the plug or into the receptacle. I hope this all makes enough sense to some people out there who know a lot more about these sorts of connections than me. Thanks a lot for reading all this! And I'm open to any ideas you might have, even if not this "IDC" stuff.

    P.S. I wish the wires from the load cell were BIGGER (and longer), but that is apparently not going to change!
  2. shortbus

    AAC Fanatic!

    Sep 30, 2009
    A photo or drawing of your proposed set up would go a long way toward getting an answer. You could also link to the data sheet for the load cell.

    As to the need for longer wires. You could solder the longer heavier wire to the existing wires and insulate the individual wires then slit a shrink tube of the appropriate size over the four wires in a bundle and shrink it to make a strain relief for the joint. By staggering the joints of the four wires the total diameter can be kept fairly small.
  3. Wendy


    Mar 24, 2008
    I've made strain gauges, I soldered the wires to the little stamps that were glued to the side of the web. The kit also included little terminals strips, similar to the strain stamps, that I used to attach the strain gauge wires going to the world with. he base strain gauge looks similar to this...

    Last edited: Apr 30, 2011