I have seen ones with mains rated contacts but I am unsure on two points:
1) is is possible to trigger easily from 5v, as that is the output of the PIC
The PIC output would drive a low power transistor via a resistor, the collector of the transistor would be connected to the 12V relay.
2) does the input of the relay need to be isolated from the PIC power supply at all?
If you buy a relay that is rated for mains switching that will be OK.
I have read posts which suggest a separate DC supply is the correct way.. but fail to understand why
So do I.!
A relay is definitely the easiest (and probably cheapest) way, I am just stuck on those two points. Would something like this be suitable?
MULTICOMP MCHRM-S DC5V