Hi, here is the requirement;
I need to monitor the 3 mains phases and detect if (a) one goes dead and (b) if the 3 phases are incorrectly sequenced. The 3 phases are being fed to 3 different pins on a 16F676.
The first part seems relatively easy; the second one I'm struggling to find a solutioion for. Am I on the right track here?
The following is for 50 hz;
I plotted the 3 phase waveforms in Excel, to better visualize the timings, and here is what I feel.
If the sequence is correct, the time between 2 corresponding points on adjacent phases would be 10.33 ms; this would be twice that if the wires are incorrectly sequenced.
Now, what makes things complex is that I'd also like to serially be outputtng the 3 readings in a cycle. How can this be done best?
I suspect the easiest solution lies in Darrel's 'Instant Interrupts' article, but I still dont quite get how the logic should be.
Has anyone on the list done something similar?
Thanks for any insight on this.
Regards,
Anand
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