How to not ZAP stuff

Discussion in 'General Electronics Chat' started by MrSoftware, Dec 3, 2015.

  1. MrSoftware

    Thread Starter Active Member

    Oct 29, 2013
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    Basically I"m clumsy and I'm looking for tips on how to not be clumsy, or to mitigate the damage from being clumsy. ;) Twice in the past few weeks I've been trouble shooting a PCB with my multi meter, in areas where higher and lower voltages are present (such as near a voltage regulator) and accidentally bridged 2 pins with my big fat multi meter probe instantly zapping the low voltage components. :eek: What are your tips and techniques for preventing mistakes when probing around areas like this? Does anyone have a favorite set of probes with much less exposed metal at the end?
     
  2. kubeek

    AAC Fanatic!

    Sep 20, 2005
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    You have a lot of options. You can measure veeeery carefully with one probe only and stick the other to some point with a crocodile clip, you can even solder wires to get better anchor points for that.
    Put a plastic sleeve or piece of wire insulation over the end of the probe so that only a tiny point sticks out.
    If you are still too clumsy then power off, attach both probes solidly to points that you want to measure, power on, rinse and repeat.
     
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  3. crutschow

    Expert

    Mar 14, 2008
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    You can grind down the probe tips to make them a smaller radius so it's less likely they will bridge between two closely spaced pins or traces.
    Other than that you can try to probe in a location and direction such as to minimize the chance of shorting if you slip off the pin.
     
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  4. cmartinez

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    Jan 17, 2007
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    Another option would be to sharpen the probe's tip with a grinder, as I sometimes do. That not only makes it thinner but makes sure that the probe will pierce through any insulation covering the PCB
     
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  5. cmartinez

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    :mad: Darn! you beat me to it by a few seconds... :)
     
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  6. #12

    Expert

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    1) Buy some of those tiny hook shaped probe ends.
    2) Get a, "standard" looking probe shank with a 'chuck' style end on it. Grind an Allen wrench to a point. Size 1/16th of an inch or 0.05 inches. That tool steel tip will penetrate any kind or amount of corrosion, paint, conformal coating, etc.
    3) Disconnect all power and solder a bit of wire to where you want to measure...then clip your hook on to that piece of wire.
    4) Apparently I'm too slow today and most of my information has already been posted.:(
     
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  7. GopherT

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    Nov 23, 2012
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    I try to most always keep the black probe of the multimeter on the ground - so I can use an alligator clip for that. I also have a narrow probe that fits cleanly into a breadboard hole.

    For the test point on the red probe, I use the thin probe tip and stick it into the breadboard, or I add an additional jumper wire to create a test point that is a bit remote from the rest of the breadboarded circuit.
     
  8. ErnieM

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    Apr 24, 2011
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    I have several probe sets from fine points to big alligator clips. Whenever possible clamp one down so you only have one probe in one hand. ALWAYS keep in mind what is around what you poke and be aware of what you can damage.

    Don't accept you are clumsy. Train yourself to be skilled.

    Training is a process demanding practice.
     
  9. cmartinez

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    Well said. I've been assembling PCBs for more than 25 years now and I still consider my abilities a work in progress.
     
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  10. Dodgydave

    Distinguished Member

    Jun 22, 2012
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    Use sharp thin probe leads, or grind them sharply as said,

    If that fails, chuck meter in the bin and take up woodworking.
     
  11. nsaspook

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  12. dl324

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    Mar 30, 2015
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    Happens to everyone every once in awhile; you get in a hurry, you get distracted, tight quarters, ...

    I use micro grabbers, sometimes with a wire. The ones in the picture below are from some Tektronix gear, the lead is homemade using female 0.025" header connectors:
    upload_2015-12-3_10-39-9.png
     
  13. #12

    Expert

    Nov 30, 2010
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    That's what I call hook style grabbers.
     
  14. KeepItSimpleStupid

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  15. R!f@@

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    I just use sharp tips with my fluke
     
  16. kubeek

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  17. MrSoftware

    Thread Starter Active Member

    Oct 29, 2013
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    Thanks guys, good tips. I'll make or acquire some new probes, and play a few games of "Operation" for practice. ;)
     
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  18. cmartinez

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    :eek: why didn't I think of that? :mad:
     
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  19. AnalogKid

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    Aug 1, 2013
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    You can buy probes with extra-pointy tips, or just file down yours. And cover the exposed tip shaft with a short piece of shrink tubing, or a couple of wraps of masking tape.

    ak
     
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  20. tom_s

    Member

    Jun 27, 2014
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    get new bifocals like i did?
     
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