>
> Rob:
>
> Just wondering, what disasters happen if you direct drive? Do you mean
> through a series limiting resistor as opposed to via an opto-isolator?
>
> Regards,
> Reg Neale

Yep... Thats what I mean.  I have tried it just to see how well it would
work.  Some triacs will switch just fine, but others will only switch
the positive cycle of the AC wave.  These triacs can be forced into
conducting the full wave by driving the gate well over the recomended
current.  Since you are using DC this is expected.  I have also found
that most of the time the triac will not switch at all.... Unless you
are totaly insane and reference your logic ground to AC N.  If you do
this it will switch but all of the wonderful noise, surges and spikes
are now on your ground plane... big mistake... :(  Anyway... all of this
has to do with my 12C509.  In a product we sell... a MID400 AC detector
is used along with a MOC3055 drive for a power triac.  The triac is used
to switch an inductive load at 1A.

Rob Tracy
FotoShield