Thanks in advance for reading this. My sprinkler system has two terminals for a rain sensor to be attached. I am making a arduino/wifi circuit that would allow me to remotely bridge these terminals, when I know rain is expected. The easy way to do this, is to just use a transistor/relay module, however I do not want the relay drawing power from the time I know rain is coming, until the time I think it is dry enough out to require me to un-bridge these terminals. I know I could do something mechanically with servo's and a slide switch, but that seems a bit Rube Goldberg. Any ideas on how I should accomplish this (I am considering a SSR, but I do not believe the voltage across the terminals are A.C.)?

 

Are there any voltages on the rain terminals........for the rain sensor?

 

How about a latching relay?

 

I haven't yet had the chance to put a meter on it, but it is designed to be connected to a simple switch (a expandable piece of cotton gets wet from rain, and presses down on a plunger type switch) with 22-24 awg wire over a long (50') run.

 

How about a latching relay?

That sounds right, do you have a link to one as an example?

 

Here is a link to a manufacturer of relays: http://www.omron-ap.com/service_support/FAQ/FAQ02822/index.asp

A specific part number available on Digikey.com: TQ2SA-L2-12V-X (Panasonic)

 

Thanks for the help. I have the relay on order.