Ac peak current meters

Thread Starter

eleceng16

Joined Mar 26, 2012
6
I've read about instrumentation to read ac RMS values (with rectifier instruments/ moving iron ... ) but how is it possible to directly read an ac peak current value?

Thanks :D
 

crutschow

Joined Mar 14, 2008
34,280
Rectifier instruments generally read peak values, not RMS.

In that vein, you use a rectifier and capacitor (to hold the peak value) to read the peak of an AC signal. If you can't tolerate the 0.6V or so drop from the rectifier (diode) then you can use a precision peak hold circuit using an op amp, with the diode in the feedback loop to essentially cancel the forward drop from the diode.
 
Top