The RPS-409A-IS is an intrinsically safe, analog ultrasonic sensor. It is a self-contained sensor in a 30mm PVC barrel housing. It is powered by 16-30VDC with reverse polarity protection. It also has a narrow beam angle, which enables it to get into tight places. A flat target can tilt up to 10 degrees and still be detected. The RPS-409A-IS has a short circuit protected analog 0-10VDC output. Example using the RPS-409A-80-IS: The output is a linear .125 volts per inch. Therefore a target placed 10 inches from the sensor will result in an output of 1.25 volts. Likewise a target placed 80 inches from the sensor will result in an output of 10 volts. The RPS-409A-IS has built in temperature compensation to provide accurate readings throughout the entire operating temperature range.