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How to properly use an ammeter to monitor an electrolytic cell

  1. Jul 23, 2007 #1
    Hi i recently acquired an ammeter with a shunt can anyone explain how to wire this so i can measure amps in an electrolytic cell. Does the positive lead have to be wired across the shunt so that it doesn't burn out the lcd display. I've never used such an ammeter so any suggestions will be appreciated.
  2. jcsd
  3. Jul 23, 2007 #2
    Connect the shunt in series to whatever you are doing, like to the battery for instance. The positive LCD lead has to be connected to the shunt where it is closest to the positive end of your battery and negative lead of LCD to the more negative end of the shunt.

    Just a precaution. The LCD display has to be powered by a separate battery. If you attempt to power it by the battery you are measuring amps from, you might risk blowing up the LCD display.
  4. Jul 24, 2007 #3
  5. Jul 24, 2007 #4


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    Staff: Mentor

    Correct. The "ammeter" is just a DVM measuring the small voltage drop generated by the current flowing through the low-resistance shunt. Different current ranges on the ammeter will often switch in different shunt resistor values, in order to keep the measured voltage large enough (10-100mV?) to give an accurate current reading on that range.
  6. Jul 24, 2007 #5
    Thanks I just tested it out and it works great. i appreciate your help everyone
  7. Jul 25, 2007 #6
    Quite note:
    Always measure current by connecting it in series
    Always measure voltage by connecting it in parallel
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