I reckon it’ll do the job, and the price is right! BTW, I’ve not completed my tests yet, but my original motivation for following your lead and getting an F303 was to test out the maths capability of the M4. It’s impressive! It’ll do an FFT on 1024 floating point values in 1.3 msecs. That’ll get you to the 512 complex pairs and it takes another 284 usecs to calculate their magnitudes. I suspect it’ll have a lot of potential for people wanting to do further analysis of the data.
Yeh, that would probably be useful if you were using shunts to measure I, and resistor dividers to measure V. Simultaneous conversions would then mean there’s pretty much nowhere for phase errors to creep in. But since you’ll always have VTs and CTs between you and the signal, I think you’re always going to have to deal with phase errors.
Yeh, I suspect you will want to slow it all down. It’ll ultimately come down to the effective sample rate of each channel. I think on those “current” channels above (i.e. the 10 of the 11 channels that aren’t channel 1) I’m sampling at 345 kHz which is way faster than it needs to be. And the “voltage” signal (channel 1), I’m sampling at 1.7MHz if I’ve done the maths right. The demo is more a demo of the potential horsepower available… those crazy high clock rates are not recommended for measuring power. Apart from anything else, you’ll need so many data points just to capture a mains cycle because each one has so little reach along the time axis.