The Duplex MW motion detector is a motion sensor with one PIR and one microwave sensor. An alarm is not triggered until both sensors register movement. The combination of passive infrared (PIR) and microwave (MW) ensures very high protection against false alarms. The reason: An alarm is not triggered until both sensors – which use technically different detection methods – register movement. Whereas the PIR sensor reacts to moving heat, the microwave sensor actively monitors the surroundings for movement (similar to radar). The transmission frequency is 9.35 GHz. The best place to install the sensor is in a corner, between 2 and 3 meters above the floor. The intruder's possible direction of movement should be at right-angles to the sensor. The viewing angle of the Duplex MW motion detector sensor is 90 degrees, and the detection range – depending on installation height – up to 15 x 15 meters. You can vary its sensitivity by means of a jumper. This way you can define the number of pulses that have to be detected before the sensor opens the alarm relay. The Duplex MW motion detector sensor has an alarm memory. If the alarm center is disarmed following an alarm, the LED on the sensor that triggered the alarm lights up. Depending on the configuration, you can also see which sensor first triggered the alarm.