> For driving the 24V solonoids I'll use a much smaller triac which
hopefully wont draw that much current!
>

Regrettably, size of triac and current drawn don't necessarily relate well
to required gate current. For ANY application where a triac gate is driven
directly by a PIC you need to look at the spec sheet and see if the PIC is
able to drive it directly. You must use the worst case figures for both PIC
and triac if you want to be sure of it always working. eg PIC will have
typical and minimum drive capability - use minimum. Triac will have typical
and maximum required gate current to trigger - use maximum. For any 5v gate
application you will want what is described as a "sensitive gate" triac. You
can get triac triggering optocouplers which themselves have triac output
stages - but even these can require quite heavy drive currents. Always check
spec sheets !!!


        RM

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