The use of two technologies—microwave and PIR—and features like anti-masking, vandal-resistant housing, large coverage patterns and three microcontroller-based sensitivity modes, make the powerful DT900 DUAL TEC sensors ideal for the harshest commercial and industrial environments. DT900/DT901 27m (90') Range Long: 18 Intermediate long: 18 Intermediate: 16 Intermediate lower: 12 Lower: 8 Look-down: 2 15m (50') Range Long: 18 Intermediate long: 16 Intermediate: 12v Lower: 8 Look-down : 2 DT900 (anti-mask) 15m x 12m (50' x 40') 27m x 21m (90' x 70') DT901 15m x 12m (50' x 40') 27m x 21m (90' x 70') Microcontroller-Based Dual Technology Microwave and passive infrared (PIR) technologies, combined with microcontroller-based advanced signal processing, provide excellent detection while virtually eliminating false alarms and costly service calls. Sensor Sabotage Prevention The DT900 Series uses Active Infrared for anti-masking to detect attempts to mask the sensor. The patented look-down lens catches saboteurs who try to disable the unit from below, while three different tamper switches deter would-be criminals from physically damaging the sensor. The patented INFORMER® function, designed primarily as a diagnostic tool, monitors for sensor blockage and can help identify a sabotage situation. Queue Logic Event Processing The microcontroller in the DT900 converts all incoming microwave and PIR signals from analog-to-digital format. If the signal is determined to be valid it enters the Queue Logic Event Process. This process stores the valid signals within a moving window of time, keeping up to eight events for each signal type. Based on the First In First Out (FIFO) concept, Queue Logic requires a sophisticated on-board microcontroller to make advanced calculations for qualifying a sequence of events as an actual alarm. Self-Test and Continuous Supervision for High Reliability This industrial-grade sensor performs multiple levels of supervision. The INFORMER function checks each technology continuously. The microcontroller conducts a self-test of the sensor’s functions at regular intervals, and reports any trouble using the on-board trouble relay. Designed for Harsh Environments Vandal resistant housing combined with a zero clearance bug guard make the DT-900 series ideal for commercial and industrial applications such as warehouses, large retail facilities, manufacturing sites and schools. Self-Adjusting Thresholds The on-board microcontroller automatically adjusts the microwave and PIR thresholds to compensate for environmental disturbances not related to actual intrusion events. True temperature compensation continually optimizes the performance of the PIR to account for changes in room temperature. Environmental noise compensation keeps common environmental disturbances such as fluorescent lights from causing the microwave to false alarm. Technology – PIR for intrusion detection – Microwave for intrusion detection – Active infrared for anti-masking (DT900)