The OSC series is a low voltage occupancy sensor that controls indoor lighting. The sensor fills the room with continuous reflective high frequency (ultrasonic) sound waves. Any movement within the sensor’s range causes a shift in the original emitted frequency. The sensor’s receiver identifies any change in frequency as motion and either turns the lights on or maintains lights on. Additionally, the sensor is designed with an isolated relay contact; which enables the sensor to interface with other systems. Small Motion Sensitivity: The ultrasonic technology provides excellent small motion sensitivity. Walk-Through: Provides increased energy savings by decreasing the time delay to 2.5min when someone momentarily walks through the monitored space. Rugged, high-impact, injection molded plastic.