3-phase energy meter

[efeixas]

Posted on July 08, 2006 at 10:35

3-phase energy meter

[efeixas]

Posted on June 18, 2006 at 12:11

Hi,

I'm doing a 3-phase wattimeter for my aplication, (a solar energy counter), I already have a hard solution(made with old operationals :p ), but I would like to change it into a soft solution with my st72334, but I'm not surehow I could made it.

One solution could reading the three phases seperated on three diferent ADC's ports by putting the zero level of the signal at middle value of my ADC (128) but that will decrease my ADC resolution from8 bits to 7 bits and I will stil have problems of offset voltages.

Another solution would be using additional ADC chip and seperate all phases in two parts direct and inverted. I can't use my micro ADC ports because they not enough (3ports V direct of each pase + 3ports V inverted of each pase +3ports I direct of each pase +3ports I inverted of each pase ) =12ports!, and micro just have 8ports.

Can anyone give an idea?

[philippe2]

Posted on July 08, 2006 at 10:35

Hello

Look at application note

AN2288 Single-phase energy meter with tamper detection based on ST7FLITE2x.

You will find lot of good insights in building an AC energy meter. Clever circuit will enable good resolution using 8bit ADC.

rgds

P. Billotte