Planning
Position on glass panes
4
49
Building Technologies
007016_i_en_--
Fire Safety
2012-09-07
4.12
Position on glass panes
Detection through glass panes
Detection through glass panes is only possible under certain circumstances.
Please observe the following points:
Glass panes must be smooth, clear, and stably fitted.
A maximum of two glass panes, each max. 5 mm thick, may be penetrated. It is
however better to only penetrate one glass pane.
The detection distance is reduced by 20 m per glass pane.
Detection is faultless when the standardized signal value is less than 5 % when
the reflector is covered.
Glass panes may never be at a right angle to the infrared ray (see example
below).
Glass panes must never be installed at an angle to the infrared ray, in which
the glass pane acts as a mirror and can reflect the infrared ray to the receiver
(impact angle = angle of reflection).
FDL
DLR
E
S
FDL
DLR
E
S
min. 5-10°
1
1
2
2
Detection through glass panes. Left: Correct use. Right: Incorrect use.
1 Glass pane
E Receiver
2 Light scatter
S Transmitter
