My multimeter eats leads.

Discussion in 'General Electronics Chat' started by Cue, Jul 31, 2013.

  1. Cue

    Thread Starter New Member

    Oct 16, 2012
    15
    0
    I have a multimeter (excel XL830L) that seems to destroy any probe leads connected to the COM socket. It's bizarre. It has destroyed 3 leads so far. Everything is in working order then when I turn off the multimeter and come back to it later I find that the lead has detached from the probe:

    [​IMG]

    This has happened 3 times on the same socket. What could be causing this?
     
  2. MrChips

    Moderator

    Oct 2, 2009
    12,452
    3,371
    Your mouse is chewing on leads?
     
  3. Cue

    Thread Starter New Member

    Oct 16, 2012
    15
    0
    The thought of some pest did cross my mind however I came to the conclusion that it's impossible. The leads detach from the bottom, deep within the tube of the probe and always the same socket. There is absolutely no way a mouse could have chewed it there.
     
  4. strantor

    AAC Fanatic!

    Oct 3, 2010
    4,302
    1,988
    Buy better leads. No way your meter can cause that.
     
  5. Cue

    Thread Starter New Member

    Oct 16, 2012
    15
    0
    Ok I'll buy "better" replacement leads but I'm 95% certain that the meter is causing this because all the evidence is pointing to it.

    I have used these leads for years without a single problem on a Robin K2027 multimeter and they've never broken on that. Even on the excel XL830L when plugged into the other terminal they have never let me down. These leads have only broken when plugged into the XL830L and only on the COM socket. I'm 95% sure something about this multimeter is causing this because these same leads work/last fine on my other mulimeters and on the other terminal.
     
    Last edited: Jul 31, 2013
  6. LDC3

    Active Member

    Apr 27, 2013
    920
    160
    If you really think it is the multimeter, you could always replace it. Mark it as some of the junk you have bought and never put to any use.
     
    Cue likes this.
  7. strantor

    AAC Fanatic!

    Oct 3, 2010
    4,302
    1,988
    You're 95% sure one way, I'm 96% sure the other way, LOL. I understand the circumstances lead you to a certain conclusion, but I know of no scientific explanation that could lend credence to your theory. Of course I don't know everything, or even close, and there's a chance you're right. If someone can give a verifiable explanation then I'll gladly eat my words, but I'm betting heavily on not having to do that.

    Uncanny coincidence can be a real bitch when you're trying to troubleshoot.
     
  8. blueroomelectronics

    AAC Fanatic!

    Jul 22, 2007
    1,758
    98
    Call James Randi
     
  9. MrChips

    Moderator

    Oct 2, 2009
    12,452
    3,371
    All together you're 191% sure.
     
    GopherT likes this.
  10. Cue

    Thread Starter New Member

    Oct 16, 2012
    15
    0
    I can think of one but I cannot explain why it may be happening. Some short lived high current occurs when I'm switching it off or because I'm misusing this particular multimeter somehow (short circuit). This particular multimeter is unfused and the wire in the probes may be thin enough to burn out through joule heating. So I can think of how but I cannot think of why this may be happening. It may well be coincidence but I think the chances seem fairly slim at this point. The first time it happened I thought it was strange, the second time coincidence, but it's happened a third time now. Only on this multimeter, and only on that terminal. Could it be caused by static perhaps? I know static can sometimes blow fuses. I do occasionally just leave the multimeter on static prone materials like carpet.

    So what do people recommend I invest in at this point. New probes or new multimeter? Currently I feel like getting new leads just to see if it happens again.
     
  11. blueroomelectronics

    AAC Fanatic!

    Jul 22, 2007
    1,758
    98
    New quality probes, they shouldn't have come apart so easily.
     
  12. BobTPH

    Active Member

    Jun 5, 2013
    789
    114
    Another possibility: someone is playing a gag on you.

    Bob
     
    djsfantasi likes this.
  13. ErnieM

    AAC Fanatic!

    Apr 24, 2011
    7,395
    1,607
    Your honor, the complainant by his own words admits these probes are several years old and thus due for replacement.

    I move the case be dismissed.
     
    shortbus and GopherT like this.
  14. THE_RB

    AAC Fanatic!

    Feb 11, 2008
    5,435
    1,305
    Actually they are +0.5% sure, on average. ;)
     
  15. Cue

    Thread Starter New Member

    Oct 16, 2012
    15
    0
    objection your honour. I've used this make/type of leads for years, the new ones this multimeter destroyed (after it destroyed the first) where but a few weeks old. :p
     
  16. paulktreg

    Distinguished Member

    Jun 2, 2008
    612
    120
    It's strange you show a photograph of the victims rather than the suspect.

    The cause isn't your DMM, it must be the cheap leads you are buying? ;)
     
  17. WBahn

    Moderator

    Mar 31, 2012
    17,788
    4,808
    I would look at whether you are treating leads plugged into the COM socket differently than leads plugged into the other ports. Perhaps you are stressing them some way.

    I vote for better quality probes, in any case.

    And coincidental happenings of three things are not THAT improbable and, in fact, you expect them to happen every so often by pure chance.
     
  18. djsfantasi

    AAC Fanatic!

    Apr 11, 2010
    2,815
    835
    It is strange that this only happens during his absence. Someone here suggested mice, but I suspect a culprit with half as many legs.
     
  19. #12

    Expert

    Nov 30, 2010
    16,355
    6,852
    It seems the probe end comes off. Maybe you can find probes that you can disassemble and attach to the wires. I have maybe one left and don't remember where I bought it (many years ago). While you're at it, watch for the kind that can have the pointy end replaced. I install a .05 inch Allen wrench and grind it to a point. Being machine steel, it can penetrate any kind of corrosion, paint, or practical joker.
     
  20. BobTPH

    Active Member

    Jun 5, 2013
    789
    114
    To eliminate the practical joker possiblity, leave the leads apparently connected to the multimeter, but really connected to the live side of your house wiring.

    Bob
     
Loading...