Have a poke around in forum791. There are some really good links which have previously been posted on PLC basics, and I think it would be a justifiable cross-post for you question of you didn't find what you were looking for. I don't recall anything specifcally for FP, but that is probably not surprising given the universal nature of PLCs.
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One day my ship will come in.
But with my luck, I'll be at the airport!