Although the contactor to stop the turbine when batteries in float looks a great Clipper anti-smoking device I was wondering about
having the contactor switch in some of those 'designed to glow red' radiant heater elements (nichrome wire type?) as a dump.
I suppose there's all sorts of things that could be thought up to use power just to keep turbines running after the day is done. We have an all-electric off-grid home and the biggest challenge over the years was coming up with a way to reliably heat 110 gallons of water to at least 130 degrees once every 4 days so we never run out of hot water. I've played with just about everything to do that, including direct solar water heating that freezes up in the winter and don't work anyway because the sun don't shine then.
I've been able to accomplish it by using a combination of wind and solar power (and auto start/stop generator when necessary). But the Classic controller has been what's made it possible to do and still take good care of the batteries. For the first time in history our batteries get properly bulk charged, absorbed for the precise time they need it, then floated - while simultaneously keeping the RE sources at full power until the stats kick the water heaters out.
When all that's done I just want to get on with my day and do other things like go fishing. So I've come to the conclusion of why leave a turbine running just you because can when you don't need it? The goal is not to set a World Record for energy production. It's to live comfortably off-grid without having to give up the things that "normal" folks enjoy and take for granted.
We bought a new Trane XR-13 2-ton Central A/C unit for our house because we decided we're not going to live another summer in torture in the heat. It's going to take power to run it but I'm confident we can do it by just throwing more solar panels at the problem.
So in the end there's only so much practical use for "opportunity loads". For the things you need every day like hot water or air conditioning in hot weather, it just takes raw power. BUT - when you get to the point where we are where you got enough raw power to run that stuff, you have to have a way to turn that raw power off when you don't need it too - and it's got to be automatic so you don't have to think about it or mess with it.
The Classic is more than just a Charge Controller. As you and I both know, boB has put enough features in those AUX ports so you can run and control just about any dang thing you want, from using excess power for heating water while still charging the batteries properly, to even having the thing turn your yard light on at dusk and off at dawn with that feature on the AUX1 port. There is no other controller that even comes close to what it can do. So now having a surefire way to shut all my turbines down in one fell swoop when the system drops into float for the day, and start 'em back up when the system drops out of Float is just icing on the cake. Why wear turbines out just because you can?