Optical Rain Sensor Use it to measure rainfall or to close a skylight when it starts raining.
The RG-11 Rain Gauge senses water hitting its outside surface using beams of infrared light. It uses the same sensing principle used in millions of automotive rain sensing windshield wiper controls. Consequently, it is remarkably inexpensive, at just $59 for a single unit.
The RG-11 is optical– not mechanical, chemical, or conductive. Consequently, it is far more rugged, sensitive and reliable than any other technology. The sensor is extremely sensitive, and virtually immune to false trips. Yet, it is completely unaffected by jostling and motion. There are no exposed conductors to corrode, and no openings for bugs to crawl into. There is no place for leaves or other debris to collect.
The RG-11 bounces beams of light within the lens. When drops hit the outside surface, it allows some of the beams to escape. The RG-11 detects the change in beam intensity, and determines the size of the rain drop that caused the change. The sophisticated circuitry and Digital Signal Processing detect tiny rain drops, and reject the effects of ambient light disturbances.
The RG-11 detects the surface condition, caused by dirt, contaminants, aging, and other factors. It properly compensates the data, making the device virtually impervious to environmental factors.
Sophisticated software gathers data from individual raindrops and implements a proper control strategy for the selected mode. The system can detect individual drops of under half a millimeter. The tipping-bucket emulation algorithm can register accumulations of just one ten-thousands of an inch– a hundred times more sensitive than a typical tipping bucket. The RG-11 borrows technology that was developed over many years for automotive rain sensing windshield wiper controls. We can offer the RG-11 at such a righteous price because the development was largely paid for through our research in the automotive field. See the RG-11 instructions for information about how the RG-11 responds in the different modes.
But don’t worry about the complexity of the Rain Gauge. Think of it as a functional block that encapsulates the rain sensing function for you– reliably, low maintenance, and at a low cost. The perfect Rain Sensor for your application.