For years I have had my observatory roof automated and all that time connected to an AAG CloudWatcher, so the roof closes on detection of inclement weather.
The risk with that scenario is that there's a computer involved in the loop. The PC could fail completely, software could operate in an unexpected way, etc such that there remains a small chance the roof wouldn't close if it rained.
I have now got a solution to this problem working!
A cheap rain sensor used normally in the agricultural industry is hooked directly in to my relays for the roof such that if it detects anyrain at all it flicks the relay and the roof closes. There's nothing the computer can do then to open the roof because it still has the circuit closed. When it dries the circuit opens and normal control resumes.
Very happy to finally have this fool proof protection in the loop.
Attached is a pic of normal (no light), green (rain detected) and below is a dropbox link to a video where you hear the roof close.
https://www.dropbox.com/s/6omaf1vkyd...%20pm.mov?dl=0
Roger.