15
6.2.5.
The DIP switches “5”, “6”, “7”, “8” are used for setting the detector’s sensitivity. When the
DIP switch “5” is set to OFF (SPECIFIED) other three switches define one of the eight alarm
thresholds: 10%, 15%, 20%, 25%, 30%, 35%, 40%, or 50%. Table 3 shows the match between
positions of the DIP switches and defined thresholds as well as recommended detection ranges for the
selected thresholds.
6.2.6.
When the DIP switch “5” is set to ON (ADAPTIVE) position then the positions of switches
“6”, “7”, and “8” specify the kind and number of reflectors to be used in the detector operation. It is the
case when the detector can correctly estimate the monitored distance based on the given gain and thus
to find out correctly the alarm threshold for this distance. Table 4 shows the match between positions
of the DIP switches and the suitable types and numbers of reflectors to use.
Table 4
Switch Number
Type and Number of Reflectors
5
6
7
8
ON
ON
Х
Х
One XS-Type (Extra Small) reflector
ON
OFF
OFF
OFF
One S-Type (Small) reflector
ON
OFF
ON
OFF
One L-Type (Large) reflector
ON
OFF
OFF
ON
Two L-Type (Large) reflectors
ON
OFF
ON
ON
Four L-Type (Large) reflectors
Figure 9 graphically shows average values of adaptive alarm thresholds expressed as a percentage (the
left chart) and the relevant sensitivity values in dB/m (the right chart) depending on the monitored
distance.
Figure 9
6.2.7.
There are explanatory inscriptions on the detector’s PCB near the DIP switches which facilitate
setting the selected operation tactics.
6.3.
Instructions for Aligning the Detector
6.3.1.
General Information
6.3.1.1.
Every detector must be aligned directly on site due to specificity of the beam detector
operational principle, namely the use of a narrow optical IR-beam to detect smoke. So, in order the
detector to operate correctly the maximum of the radiation pattern of its optical system should be
aligned with the direction to the reflector. The retroreflector should not be aligned if the beam angle of
incidence differs from the reflector surface normal by no more than 12 degrees, because in this case its
effectivity practically does not change.
6.3.1.2.
Actually the task of alignment reduces to selecting such orientation of the transceiver for
which the received signal is the maximum possible value for the specific distance between the
10 20 30 40 50 60
70 80 90 100 110 120 m
10
20
30
40
50
60
%
10 20 30 40 50 60
70 80 90 100 110 120 m
0,02
0,04
0,06
0,08
0,1
0,12
dB/m
