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Thread: Multimeter errors

  1. #1
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    Multimeter errors

    I just bought a Southwire clamp meter at a pawn shop for 25 bucks. Only thing I don't like about it is that the red lead shows voltage even when the black lead is still open (not touching anything). What could cause this? Can it be fixed? There were no fuses when I opened it up.

    Sent from my LG-US998 using Tapatalk

  2. #2
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    Quote Originally Posted by Abbasis View Post
    I just bought a Southwire clamp meter at a pawn shop for 25 bucks. Only thing I don't like about it is that the red lead shows voltage even when the black lead is still open (not touching anything). What could cause this? Can it be fixed? There were no fuses when I opened it up.

    Sent from my LG-US998 using Tapatalk
    That’s normal

  3. #3
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    But I can't feel it's normal if I happen to observe this.

  4. #4
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    Floating leads will pick up stray voltage from all sorts of places, particularly from 60Hz AC all around you. Many multimeters have a 60Hz filter that drops most of it, but that one might not. As long as the voltage goes to zero when you short the leads, and you've tested it on a known voltage, I wouldn't worry about it.

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  6. #5
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    If it bothers you can you change the range higher so you don't see the mA bouncing around?

  7. #6
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    Quote Originally Posted by JoeyMarquez View Post
    But I can't feel it's normal if I happen to observe this.
    Don’t connect only one lead, and your problem will be solved.

  8. #7
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    Quote Originally Posted by Abbasis View Post
    I just bought a Southwire clamp meter at a pawn shop for 25 bucks. Only thing I don't like about it is that the red lead shows voltage even when the black lead is still open (not touching anything). What could cause this? Can it be fixed? There were no fuses when I opened it up.

    Sent from my LG-US998 using Tapatalk

    And there in lies a relatively common issue with some digital multimeters. Incorrect readings because the operator fails to read the display properly. Mv Millivolts.....V Volts......Ma Milliapms.....A Amps, and so on. If you are aware of this characteristic, it's a non- issue.

    In general, higher quality digital meters are more sensitive, and their readouts will have a tendency to float somewhat with their leads disconnected.

    In addition, in certain conditions, digital meters can also have a tendency to dampen their readouts, or sometimes be influenced by high electromagnetic fields such as those present in some frequency drives.

    Just a couple reasons to carry a higher quality back up analog dinosaur meter.

  9. #8
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    Quote Originally Posted by Artrose View Post
    And there in lies a relatively common issue with some digital multimeters. Incorrect readings because the operator fails to read the display properly. Mv Millivolts.....V Volts......Ma Milliapms.....A Amps, and so on. If you are aware of this characteristic, it's a non- issue.

    In general, higher quality digital meters are more sensitive, and their readouts will have a tendency to float somewhat with their leads disconnected.

    In addition, in certain conditions, digital meters can also have a tendency to dampen their readouts, or sometimes be influenced by high electromagnetic fields such as those present in some frequency drives.

    Just a couple reasons to carry a higher quality back up analog dinosaur meter.
    Thank you very much for explaining this problem in detail. Honestly, I hadn't heard about it before!

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