The Siemens 5WG1 series is a passive infrared (PIR) motion detector designed for indoor security and lighting automation installations. The 4m sensor range with 3000mm depth specification indicates this is a wall-mounted or ceiling-mounted unit for medium-range occupancy detection. Critical verification: confirm the detection pattern (horizontal/vertical coverage) matches your installation geometry and that the part number suffix (-2DB12) aligns with your voltage/protocol requirements (KNX, etc.).