Wiring Help with Rain Bird Sensor

I have a new cprsdbex Rain Bird sensor (and new Rachio 3). Other than color, the two wires out of the sensor appear identical (and not labeled). One wire is black, the other is red. Where do I connect these wires into my Rachio? From what I saw online, I connect one to the S1 port… but what about the other wire? And also does it matter which wire goes where?

In the app there is a diagram when enabling the sensor that shows where the wires go. I believe the red will go in the S1 or S2 (these don’t matter which one, you just need to enable the correct sensor when you enable it in the app) and the black wire goes in the black next to the S1 S2 ports (labeled 24 VAC -). Should be able to plug it in, enable it in the app and then manually trip the senor by lightly clicking it in with your finger. If everything is wired up correctly, you’ll see in the app that Rain Sensor is tripped. Once you release the sensor with your finger, it will go back to “Un-tripped” so it won’t delay any watering.

I got as far as figuring out which ports need to be used, however my hang up really is the wires. If your guess is wrong and the black goes to S1 (or S2) and red goes to 24 VAC-, will I damage anything during my test?

I just tried with a TORO sensor we’ve got laying around and red in the S1 and black in the (-) black worked. Tested by manually clicking the top of the sensor down. For that sensor, I did try switching the wires so that red was in the black, and black was in the S1, but that actually worked as well.

Not knowing how the sensor is made, I can’t give a definitive answer but I’d still guess that black goes in black and red in the sensor port. I doubt mixing up the wires would cause damage, but I don’t know much about the sensor. The Rachio should not get damaged though as that is supplying the power. Maybe someone else in the community though who has that sensor will chime in.

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