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Voltmeter help

  1. Aug 30, 2006 #1


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    Please excuse my ignorance, but I could use some assistance. I need to get a device that will test if current can pass from an electrode through a connected wire on down to a pin that connects to a computer port. (Sometimes the electrical connection fails because of a poor connection between the wire and the electrode.) I have seen this test done before using a voltmeter (it was actually set to beep when it detected a bad connection), but I'm not familiar with how voltmeters are typically constructed-- i.e. whether the feature used to detect bad connections was a standard voltmeter feature or not. (I have looked into it a bit and I believe the test I am speaking of is called a "continuity test," with the above mentioned beeping feature being a "continuity beeper," but I'm not 100% certain.)

    I'm currently looking at a cheap voltmeter that I think may be able to do the trick for me, but I'd just like some input from more knowledgeable folk on whether this device will do what I need it to do. The technical details provided on the web site are as follows :

    Product Features

    * DC current: 200micro/2m/20m/200m/10A AC voltage: 200/750V DC voltage: 200m/2/20/200/1000V Resistance (ohms): 200/2K/20K/200K/2M
    * Transistor & diode test
    * 3 1/2 digit LCD with a maximum reading of 1999
    * Low battery indicator

    Can a "continuity test" (if that is the right term) be done using transistor/diode tests? If not, is it safe to assume that the "continuity test" feature is so standard for voltmeters that I should take it as a given that this voltmeter will be able to do it?
  2. jcsd
  3. Aug 30, 2006 #2


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    A "continuity test" is really nothing more than a resistance test with a beep. The beep sounds when the measured resistance is very close to zero. Since the beep is annoying in some situations (while incredibly useful in others), most multi-meters have a special setting to enable it.

    It's a pretty safe bet that every digital mutli-meter sold today has a continuity function. If it includes sophisticated features for diodes and transistors, I'd be amazed if it didn't also have a continuity beep feature.

    If it lacks a beeper, however, you can always just set it to low-range resistance mode, and look at the display. If it's close to zero, you can even say the word beep! :biggrin:

    - Warren
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