Hydreon RG-9 Optical Rain Sensor

The RG-9 uses beams of infrared light within a plastic lens about the size of a tennis ball. The round surface of the lens discourages collection of debris, and the RG-9 has no moving parts to stick, and no water-pathways to clog. The device features an open-collector output that indicates when the selected rain intensity has been reached. The sensitivity levels are: Rain Drops, Very Light, Medium, Heavy. The duration of the positive detection is also selectable: No Hold, Hold Time 5 Minutes, Hold Time 10 Minutes, Hold Time 15 Minutes.

The RG-9 has multiple outputs: visual output via an on-board LED, Open Collector output and RS232 serial communications that provide more detailed data, including 8 near real-time rain intensity levels and allow for reading the status and configuration of the device. Power consumption of the RG-9 is very low, and the device is well-suited to solar-power applications.