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How to check AC current Through multimeter

  1. Apr 26, 2010 #1
    Hai Guys.......

    I want to check the AC current by using digtal multimeter.Please give me instruction.
     
  2. jcsd
  3. Apr 26, 2010 #2

    mgb_phys

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    No,
    Sorry - but assuming you mean household line/mains current (ie 120/230V) then anybody who needs to ask is probably not safe dealing with potentially lethal voltages.
     
  4. Apr 26, 2010 #3

    russ_watters

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    Staff: Mentor

    Last edited by a moderator: Apr 25, 2017
  5. Apr 27, 2010 #4

    mgb_phys

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    Thanks russ - I was picturing somebody with a $5 DVM and it's optimistic 10A range trying to measure the current to a water heater.
     
  6. Mar 13, 2011 #5
    I have a situation with a very small indicator lamp. The voltage is 5.4Vac. One lamp is burned out (I want to replace both). With a common multimeter in series with the good bulb, the range set to 200mA, the meter fluctuates, maximizing around 40mA. I am trying to reverse engineer the lamp for replacement, and only have a cheapo multimeter.

    DSC02932x.JPG

    Do you have any suggestions I might use for my situation?

    Thanks
     
  7. Mar 13, 2011 #6

    russ_watters

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    Well as said above, you can't find the amperage, but why do you want to anyway? You already have the voltage of the lamp...
     
  8. Mar 13, 2011 #7
    Thanks Russ.

    If I know the current draw, the voltage and the physical size I can (maybe) find a replacement bulb. Without the current draw known, the replacement bulb might draw more or less than the original and burn bright or dim.
     
  9. Mar 13, 2011 #8
    5.3volts (RMS?) AC?

    5 volts DC supplied by a mains adapter should be close enough to measure on the good bulb.
    Or perhaps you can make up with batteries and a few resistors?
     
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