Abus bw8040 xevox triplex mw vds motion detector abus bw8040 p the abus bw8040 xevox triplex mw vds motion detector is a motion sensor with two pir sensors and one microwave element an alarm is not triggered until all sensors detect movement p p the combination of microwave mw and two passive infrared pir sensors ensures almost 100 protection against false alarms the reason an alarm is not triggered until all sensors ndash which use two technically different detection methods