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clamp on ammeter ?

bjhbjhbjhbjh Posts: 11
edited 2006-03-31 12:12 in General Discussion
I have several of Westward / Grainger 6JG56 clamp on ammeter units.

They sense the magnetic field around an A/C conductor and transform it to an A/C mV signal at the output terminals. 1A = 1mV A/C is the transfer function, 0.1A to 400A is the range. They are intended for use with a multi meter.

I would like to have a stamp measure·a DC analog·to the A/C current.

Is it too simplistic to think I could use a small full wave bridge rectifier and perhaps a capacitor, to convert A/C to D/C reliably·for this·BS2 application?

Thanks,

Brian H.

Post Edited (bjhbjh) : 3/29/2006 8:27:44 PM GMT

Comments

  • stamptrolstamptrol Posts: 1,731
    edited 2006-03-30 00:48
    Brian,

    You've got the right idea, but the voltage drop on your bridge will hide the real voltage.

    To overcome the problem, you will use an op-amp circuit called a "precision rectifier" which electronically makes the voltage drop on the diodes "disappear". You can build it as either a full-wave version but I found the half wave version gives very acceptable results.

    Just Google it or look in most electronics texts at senior community college or university level.

    Cheers
  • bjhbjhbjhbjh Posts: 11
    edited 2006-03-31 12:12
    Thanks Stamptrol.

    BJH
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