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Quick disconnect test connectors

  1. Feb 12, 2014 #1
    Looking for ideas...
    At my work, we test a number of products that come with flying leads, using this kind of connector:
    http://www.digikey.com/product-detail/en/33-1404/GC400-ND/258507
    I'm looking for something a little more durable. These things have plastic clips to hold the leads in the connector, and they tend to grind down with many insertions until they no longer have enough material to hold a lead in place. I have searched around for a higher quality version of this, without much luck.
     
  2. jcsd
  3. Feb 12, 2014 #2

    berkeman

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    Can you make something based on pogo pin contacts? Some sort of a hold-down actuator for each lead that pushes it down on a spring-loaded pogo pin...
     
  4. Feb 12, 2014 #3
    It might get a bit complicated. The products have up to 12 leads.
    I should probably mention that we have many test boxes like this - maybe 100-200 of them. So an off-the-shelf solution is probably the way to go, rather than having to do a mechanical design.
     
  5. Feb 12, 2014 #4

    berkeman

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    Can you post a picture of typical leads? What wire gage? Solid or stranded wire? How far back are they stripped?
     
  6. Feb 12, 2014 #5
    Typically 22AWG, but some products vary, maybe 24 to 18 ga. Stranded wire, stripped 1/4 to 1/2 inch, sometimes tinned, usually not. The leads are generally 6 or more inches long. The products are built in batches of just a few to hundreds.
    I'm sure you can see how this would be hard on the crappy plastic connectors...
     
  7. Feb 12, 2014 #6

    berkeman

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    Hmm. How about using solid copper bus wire, about 18AWG, and just quickly wire nutting each wire onto a bus wire? The bus wires would be captured in something (wood or plastic) so they are rigid and don't move, and they are spaced far enough apart to make room for your hands twisting the wire nuts.

    After you use a wire nut for about 100 times, you can toss it. They are cheap. And make the capture fixture for the copper bus wires so that it's easy to replace the bus wire pieces when they wear out. Actually, you could start with the bus wire pieces about 5" long, and trim 1/2" off every few hundred tests to get longer life...
     
  8. Feb 12, 2014 #7

    dlgoff

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    I like this idea.

    Would this be an option? May be a little more expensive (?)

    alligator-clip-test-leads.jpg
     
  9. Feb 12, 2014 #8

    jim hardy

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  10. Feb 13, 2014 #9

    meBigGuy

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  11. Feb 13, 2014 #10
    Gator clips.... been there, done that. The leads on which the clips are mounted wear out very quickly.
    Those Fahnestock clips are a thought... haven't seen those in years.
    Most of the "pushbutton terminal block" stuff is just too small for this kind of thing. Production would scream if they had to use some little tool and squint in order to connect and disconnect 12 leads on 100 units.
     
  12. Feb 13, 2014 #11

    Averagesupernova

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    tfr00 I don't think you get it. Concerning post #8 you would fasten the alligator clip to something solid then the lead attached to it would never move. You just push on the alligator clip and it opens up to accept the lead. I have built a lot of test fixtures over the years for production and the alligator clip mounted solid to a surface is a good idea.
     
    Last edited by a moderator: Feb 13, 2014
  13. Feb 14, 2014 #12
    You're right I didn't get it... when I see a picture of alligator clips on the end of leads, without further explanation, that what I think of. But yes, that also seems like a good idea.
    Thanks for the ideas, folks.
     
  14. Feb 14, 2014 #13
    Also - how long is the test process - can you use an A/B switch and have 2 sets of connectors, one is being connected/disconnected - as the other is under test? - This may allow the use of a more robust connector, I have to think that there a good / better solution out there for this - but I am not finding one.
     
  15. Feb 14, 2014 #14

    meBigGuy

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  16. Feb 14, 2014 #15
  17. Feb 14, 2014 #16

    berkeman

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    Do you have an in-house machine shop available as a resource? If so, it would be pretty straightforward to make easy-to-use hold-down assemblies based on standard test fixture clamps like these:

    http://cloudfront.zorotools.com/product/large/3CWX7_AS01.JPG
    http://cloudfront.zorotools.com/product/large/3CWX7_AS01.JPG


    EDIT -- Use a non-conducting bolt/hold-down, pressing the stripped wire end down on a conducting pogo pin or spring finger.

    EDIT 2 -- And in case it's not obvious, the receiving fixture should have V-grooves to accept/guide the wires into the hold-down part...
     
    Last edited: Feb 14, 2014
  18. May 30, 2014 #17
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