Say for example I want to attempt driving the triac directly without an
opto-coupler, how would I connect the triac and its AC load to the =
driving
pin of the PIC?

If anyone has a schematic of a sprinkler controller showing this =
coupling it
would be appreciated =3D).

--
Andr=E9 Miller =09

-----Original Message-----
From: John N. Power

> If the optocoupler fails(drastically) there is no guarantee it will=20
> continue to isolate.

> All the irrigation controllers I've seen have used triacs with no=20
> optocouplers.

> I'm of the opinion that the "C" equivalent of an optocoupler is a GOTO =

> - in other words, if you are using one, you should really think long=20
> and hard, because there are very few reasons to use them.

Of course the optoisolator will fail if the triac shorts, but it is =
easier
to replace a generic IC than a programmable chip with a proprietary =
program
in it.

John Power

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