Siemens Cerberus DLO1191 Manual page 17

Signal [%]
150
140
130
120
110
100
90
80
70
60
50
40
30
20
10
0
Siemens Building T echnologies
Cerberus Division
"Smoothing filter"
Smoothings
A C
A C
A C
Measured
value
3 sec. 12 sec.
0 sec.
Three "smoothing filters" A, B and C are used. They are characterized by the time it takes
to reach response threshold 3 of the corresponding sensitivity setting.
If the smoothed signal reaches response threshold 1 or 2, in the interactive system the
corresponding mode is activated by means of the corresponding danger level. These le-
vels are not evaluated in the collective system.
If the smoothed signal reaches response threshold 3, the alarms in the alarm counter are
added up. Upon reaching the given value, danger level 3, i.e. an alarm is activated.
According to the diagnosis made, other alarm parameters are automatically selected:
Diagnosis "Fire or slowly-developing fire"
Diagnosis "Noise or repeated interruption"
Diagnosis "Test filter"
Smoothing filter B filters out reflections.
Reflecting or shining surfaces, which are too near at the path of the beam, can impair the
detector.
Smoothing B > actual compensation value x 1.5 = reflection
B
NFW x 1.5
0% compensation value
(NFW)
30% response threshold 3
(high)
50% response threshold 3
(standard)
65% response threshold 3
(low)
48 sec. Time
⇒ alarm activation after ≤ 6s
(smoothing A + 20 alarm counts)
⇒ alarm activation after ≤ 16s
(smoothing C + 20 alarm counts)
⇒ alarm activation after ≤ 10s
(smoothing A + 40 alarm counts)
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