Michael Park wrote:
> What's a good way for a PIC to control (on/off) a crockpot? (120 VAC, a
> couple hundred watts.)
> "Good" in this case means simple, cheap, and most importantly, safe.
> I'm a bit scared of high voltage, and I consider anything over 5V high
> :)  I'd just go with a relay, but I expect there'll be arcing when the
> contacts close and that makes me nervous. Better ideas?

Since you had to ask, keep it simple and use a plain old relay.  Get one
rated for the current, and it should last quite a long time.  Temperature
can't change that fast, so you should be able to get perfectly fine control
and not switch the relay more than once every 5 seconds, probably longer.
When the relay wears out after 10 years, replace it with a new one.

I once made a darkroom water bath temperature regulator that switched a
consumer immersion heater on/off as needed every 64 power line cycles.  It
worked incredibly well and was still working last time I tried to use it,
which was probably 15 years or so after it was built.  By the way, this was
built in 1980 and didn't have a PIC in it.  The logic was just a comparator,
a flipflop, and a 6 bit counter.


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