Wiring a Rain Sensor into a Richdel 500PR Controller

Owner has a 2‑wire rain sensor and needs to connect it to a Richdel 500PR.

Wiring Method

1. Split the sensor wires inside the controller.
2. Remove the common (C) wire from its terminal.
3. Wire‑nut the common wire to one sensor wire.
4. Insert the other sensor wire into the C terminal.

This puts the sensor in series with the common, interrupting power to all valves when wet. Test by pouring water on the sensor.