Measuring three phase power

[GabYoung92]

I'm looking at somehow creating a circuit to measure three phase power, however I'm not sure of the approach I should be taking.
The plan is to interface the measurement of current + voltage to a micro through isolation to calculate power, phase, frequency etc...  to be outputted to a computer to be logged.

I understand how using a shunt will convert the current to a voltage.  It's just, how should it be arranged? 

[notsob]

This App Note and chip may be of use

http://www.analog.com/static/imported-files/application_notes/2698536550528608457AN641_0.pdf

http://www.analog.com/en/analog-to-digital-converters/energy-measurement/ade7752a/products/product.html

Cheers

[GabYoung92]

Thanks, that is definitely an option.

Just curious, would it be possible, and not too silly to use say an atmega8 to measure the waveforms and do the calculations?

[notsob]

Have a look at Silicon Chip issue 190-191 July Aug 2004, they have an energy meter (single phase) using a sister AD chip and a PIC micro

[penfold]

Just as a side though I had whilst reading this, when it comes to isolating the voltage measurement, has anyone tried putting a micro with adc on the primary side and isolating a digital comms signal coming from that? Its not something I've tried, I just always find isolating digital signals a lot more preferable to analogue ones