How does PIR detection work?
PIR- (Passive Infra Red) is a passive sensing technology, meaning that the detector does not emit any IR radiation. The radiation source is the human body and all the objects in the field of view of the detector, which emit thermal heat radiation.
The thermal energy reaches the PIR sensor via optical means, such as lenses or mirrors, which are structured in segments. A PIR sensor consists typically of dual IR (Infra Red) elements that convert IR energy to voltage.
Each segment in the optics, with 2 dual sensing elements in the sensor, creates two fields of view collecting the IR radiation. The field of view of the detector is determined by the pattern and the amount of the segments in the optics.
How does Microwave Detection work?
The Microwave channel is an active channel. The detector transmits an electromagnetic signal and compares the reflected signal from all objects in the protected area. A moving object is identified using the Doppler effect of comparing transmitted and reflected signals. The Doppler signal is analyzed and if it suits the detection criteria it will generate a MW alarm. The microwave channel is very sensitive to movement and has much higher detection capability than the PIR channel. On the other hand - it is prone to false alarms in cases that it is not installed properly (MW not adjusted to the room size) due to the fact that it can pass walls.
How do Dual Technology (PIR & Microwave) detectors work?
The PIR and Microwave channels on their own are not immune enough to false alarms: PIR is sensitive to thermal radiation interferences. MW on the other hand is sensitive to radio frequency interferences. Combining these technologies dramatically raises the detector immunity, which leads to a low false alarm ratio. The improvement in the false alarm ratio is achieved because both technologies have to detect simultaneously in order for an alarm to be generated.
NOTE: When used with Sensaphone, BAYweb, or WisDom, this requires a 12VDC transformer (pn TH120045) sold separately.
- Sway Recognition Technology for recognizing and eliminating targets that sway but don't move more than a set distance (bushes, tree limbs, etc.)
- Digital Correlation Technology for eliminating false alarms from pets, reflections and rapid temperature changes
- 1.0m to 2.7m installation height
- A wide range of swivels for wall, pole, or barrier application
- Active IR anti-mask and anti-vandal wire protection for all brackets
- IP65 environment rating
- Extensive remote control and diagnostics when installed with RISCO Group's ProSYS Integrated Security System
- 4 active IR channels for Anti-Mask and "dirty lens" alerts
- Protective shielding for blocking out white light, allowing only IR energy to reach PIR sensors
- Hood - provides protection from sun, rain, snow, hail and birds