I'm tired of trying to remember to switch off the controller every time it rains, or is forecast to rain. I want to add a rain sensor to my system. I have a system that uses an Irritrol Rain-Dial RD-900 controller. I have been poking around trying to figure out how to install this rain sensor into the system. I see on the circuit-board that where it reads "Sensor +/-", but there are no screw-down mounting points like there are for the zones. My first question is this - can I add a rain sensor to this controller? Can a rain sensor be added to any controller/system? If so, how? Assuming that I can add one - which sensor should I go for? Wired/wireless? Thanks in advance.