PICs on a bus . . . ?

[Charles Linquis]

If you have a better idea, I'm open to it. Yes, you can sample slowly if you can tolerate a longer-term average (like you would need to display on an LCD). I realized that even with low sample rates, I would sample every part of the waveform eventually. But I needed an "electronic circuit breaker" that had to respond on a cycle-by-cycle basis.

I proved that I could respond in one cycle by connecting a bridge rectifier + resistor + FET across the load and connecting the gate of the FET to a pin on a PIC development board then bringing the the gate high for 17 ms. It worked and the circuits are in the hands of a happy (and very demanding) military customer.

[Charles Linquis]

I went back and read the entire thread, and realized I was incorrect when I told ibralfy that it was necessary to sample often (that was *my* requirement). Aratti, you are correct when you imply that you don't a high sample rate. 20 or 30 samples between each LCD update should be enough.

But ibralfy, if you sample slowly, you need to make certain that you aren't sampling at a sub-harmonic of the line frequency.