Ampac FIRERAY 100R, Product Manual

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FIRERAY PRODUCT GUIDE
Page 10
4.3.4 Atrium
If the Optical Beam Smoke Detector is to be placed in an Atrium, or near glass / polished surfaces,
the Receiver / Reflector should be offset from the central line of sight, and angled back to the
Transmitter
This can be either on the vertical or on the horizontal axis, or a combination of both.
In the instance of a Reflected Optical Beam Smoke Detector, the reflected infrared light beam from
the Reflector will be returned to the Receiver in the normal way.
The purpose of this approach is to detect the rising plume rather than the smoke layer. For this
approach, supplementary detection using Optical Beam Smoke Detectors close enough to each
other to assure intersection of the plume is installed at a level below the lowest expected
stratification layer.
The spacing (X4) between Optical Beam Smoke Detectors is based on the narrowest potential width
of the plume at level detection (X5); typically X4 is 25% of X5