currunt meter with CT

[Micro_brain]

Hello Electronics frindes,
Im looking for any suggestions for a PIC Controlled Current meter(0-25A) with PIC16f72
I read current by CT, if load=25amp(3vac) , if load=1amp(.3vac) ... how filter this low volt with bridge(OA79)
in other case,
when I load 60W bulb to my ammeter ,then displyed 0.2amp (Ok)
but when I load 40W tube (electonic ballast)to my ammeter ,then displyed 12.5amp (error)
how can solve this problem.
Sorry my bad English ........... thanks in advance. Micro_brain

 

[clairvoyant13]

40W tube generates a lot of harmonics and 60W bulb doesn't.
Use low-pass-filter.
Bye

 

[Micro_brain]

Thanks clairvoyant13
I think a doubt .... if I use a low-pass-filter.
suppose I use a load 1amp with serial diode(half cycle use)
I expect result= .5amp ,
is the low-pass-filter capacitor chrges the peek?

Micro_brain

 

[garg29]

Micro_brain if you can put your circuit digram i think i may help you out further

 

[Micro_brain]

Ok grag
this is my circuit
Micro_brain

 

[IanP]

There is one important thing missing in your circuit: burden (or load) resistor ..
Take a look at this example:
**broken link removed**
and see how can you modify your design to rectify this issue ..

Regards,
IanP