That is a neat calculator! I'm going to bookmark that.
Knowing that this is a bug, and what's causing it is very handy information.
And I've thought of another way we could get around this:
In the strategy, I could set up a group of float variables so there is one associated with each of the down timers.
I'd set them all to zero initially. Then I can have the strategy monitor them all, and if any one changes from zero, I'll just move that new value into the down timer, then move zero into the variable again, and go back to looking for it to change from zero, ready to do it all again.
That's sneaky, but it seems like it would work. I'll try it out when I get to where the system in question is set up later tonight.
Just knowing that it's not something I'm doing wrong is actually very helpful, and I appreciate your time and the way you, and Opto 22 respond so quickly to our questions. You guys are the best!