On 04/28/2017 10:15 PM, DoN. Nichols wrote:
On 2017-04-27, wrote:
On 04/26/2017 9:48 PM, DoN. Nichols wrote:
...

But he was looking for something mechanical -- or with a minimum
of electrical, so something like what I pointed to, with a couple of
relays, could do it -- with minimal battery backup. And the learning
curve, with all of the options which can be set in the controllers, may
be a problem.
...

Actually, re-reading his original post, don't need battery backup, use
the NO contact so will open on loss of power. Set the hysteresis value
on the reclose coming back up to protect restoration if were to be
cold-enough for freeze to have occurred. That's doable with the little
board I posted link to simply by programming the builtin firmware; no
coding needed.

How will the board continue to work without backup power?

....

That's the point; it doesn't need to.

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