DMM-11A Fuse open?

Discussion in 'General Electronics Chat' started by tracecom, Sep 11, 2014.

  1. tracecom

    Thread Starter AAC Fanatic!

    Apr 16, 2010
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    The DMM-11A fuse in my Fluke 115 seems to be open. How could I have done that? I don't want to do it again.
     
  2. alfacliff

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    Dec 13, 2013
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    the usual way, measureing volts while in the amps position. almost everyone has done this.
     
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  3. wmodavis

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    Oct 23, 2010
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    Always keep spare fuses.
     
  4. tracecom

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    Do you mean with the probes in the amps position and the dial in the volts position?
     
  5. SgtWookie

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    Jul 17, 2007
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    Those fuses are rated for 11A, 1KV, and are expensive. DO NOT try to substitute any other fuse than specified, as the life you lose will be YOURS!

    As mentioned, you in some manner had your meter configured to measure current (probably the 10A range) and you tried to measure voltage.
     
  6. Sensacell

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    Jun 19, 2012
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    Every meter I have ever used seems to have a blown fuse, it's just too easy to do.
     
  7. sea_goin_dude

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    Apr 18, 2014
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    Blown fuses are much better than an exploding meter. Been there called into job middle of the night one time with a meter (amprobe) that I didn't like anyway ?? and half asleep. Well I replaced a blown fuse (600 volt circuit) everything would have been fine but I thought i'd check the voltage one more time before I left. 600 volt 3 phase and I had the meter on OHMS from checking the fuse out of the circuit, and luckily I had some long leads and the meter was laying on a table and I was up on a ladder and the meter almost EVAPORATED. The battery did evaporate. and a supervisor who was watching the meter almost had a heart attack. Funny now but not at the time. Maint boss said next day that if I didn't like the meter I didn't have to blow It up that he would have bought me one that I wanted. :) I have always used Fluke meters and have never had a problem and never seen one of them blown up.
     
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  8. profbuxton

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    Feb 21, 2014
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    Many years ago two electricians were killed by using an ammeter to measure volts on a 415v main switchboard bus bars.
     
  9. alfacliff

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    Dec 13, 2013
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    we had an electrician out here a few years ago taht tried to measure 4160 volts on an air compressor motor with a simpson 260 vom. didnt get hurt, but all that was left was the probes. in the old days of multimeters with meters, measureing volts whiloe setup for amps would at least end up with a bent meter needle. there were a lot of meters with bent needles back then.
     
  10. tracecom

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    I ordered three replacement fuses: $6 each including shipping. Digikey and Mouser wanted $41 each; what's up with that?
     
  11. gerty

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    Aug 30, 2007
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    I ordered three replacement fuses: $6 each including shipping. Digikey and Mouser wanted $41 each; what's up with that?
    Where did you find them for $6 ? We have a few of those meters here, and the fuses were $18 IIRC.
     
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  12. MaxHeadRoom

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    Jul 18, 2013
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    I witnessed that a few years back, it was the flash-over that harmed them rather than shock, fortunately they were only received burns.
    Max.
     
  13. tracecom

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  14. GopherT

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    Nov 23, 2012
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    It's about time they lowered the prices on sizes that fit meters. Last time I replaced mine, I spent $18 and bought a spare. The same size/series at a different amperage above or below were $5. What a scam that was.
     
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  15. profbuxton

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    Feb 21, 2014
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    Yes , Max, it was the continuing flash that killed those two guys not shock. The current capacity of the bus bars was so high it just didn't trip the protection till it was too late.
     
  16. subtech

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    Nov 21, 2006
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  17. MaxHeadRoom

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  18. GopherT

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    No, probes in amps position and dial in amps position (from a proper amperage-reading setup). Then, without making any adjustments to the meter, accidentally trying to measure volts. Fuse pops immediately if your power source can supply 11 amps (even a large capacitor can pop one running battery-operated devices).
     
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  19. Wendy

    Moderator

    Mar 24, 2008
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    You can always replace a fuse with a smaller amperage device. All it will do is blow before it normally should, but the protection is still there.
     
  20. Lee697

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    Aug 31, 2014
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    I recently bought a new Agilent DMM, it emits a continuous warning tone whilst the meter is set on voltage and leads set for current.... I think it has saved me a fuse or two already! :)
     
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