Question
Hello Jim, I will try to keeep this short.I have a 6 zone sprinkler system controlled by a Imperial Valet Timer 24V.This system was installed in 1988 and still works fine.I would like to add a ORBIT 57071 Wireless Rain Sensor.The question is how do I wire this unit to fit.When I disassembly the timer I see a 24V transformer with 4 wires on it,which wires do I use to connect the 24V for the sensor?Next as I said I have 6 zones and I also see the 6 wires coming from my zones and the 6 wires from the timer connected together,I also see an extra black and a white wire(common spelled on it).1 black/1white come from the zone valves and 1 black/1white from the timer.These are connected together(black to black/white to white.Can I add an ORBIT sensor to this system,if so how do I wire this mess.Look foward to your reply.

Answer
Hey David, I hope this helps. I haven't installed an Imperial for about 15 years, but it is an excellent controller. Lets start with the 24 volts first. You say you have 4 wires coming out of it, two on top and 2 on bottom. Are 2 of the wires hooked to 110volts? If so, then the other two wires would be the 24volts. If not, what I would suggest would be to take a volt/ohm meter and try each wire one at a time to determine your 24 volts. Now as far as the other 2 wires are concerned. Dis-regard the extra black and white wires that are not hooked to anything. Disconnect the common field wire(white) from the common wire (white) from the controller. Now one of the wires for the sensor will hook to the common wire(white) from the controller. The other wire will hook to the field wire common(white) that you just un-hooked from the common wire from the controller. Basically the sensor is a switch, and when it is activated, will bread the continuity in your common wire, and not allow any continuity in the common wire to the valves, thus not allowing them to work. Let me know if I can be of further help. Thanks and have a great day.