Commissioning
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ASD 531, Technical description, T 140 416 en
7.6.1
Reading the airflow
The airflow is indicated on the LED bar (on the default installation) to the left of the control elements. If the two middle LEDs
are lit, the airflow is 100% (airflow at the time of the initial reset). A green LED means deviation in the tolerance range accord-
ing to Fig. 43. A yellow LED indicates airflow outside the tolerance. The sampling tube network must be cleaned (AF–) or in-
spected for pipe breakage (AF+).
Fig. 43 Airflow tolerance
Meaning
: Value < 100% = direction pipe blockage / > 100% = direction pipe breakage
Notice
According to EN 54-20 a change in the airflow that is greater than ±20% must be reported as a fault. After an ini-
tial reset, the airflow shows 100% in the ASD 531 aspirating smoke detector when the sampling pipe is correct
and clean. When switches 1 + 2 of the
Airflow
Dip switch are on
OFF
, any change in this value greater than ±20%
– i.e. below 80% or above 120% – triggers an fault after the
LS-Ü
delay time of 300 s has expired.
AF+
AF-
±20%
±30%
101 - 105%
106 - 110%
111 - 115%
116 - 120%
>120%
99 - 95%
94 - 90%
89 - 85%
84 - 80%
<80%
101 - 107%
108 - 115%
116 - 122%
123 - 130%
>130%
99 - 93%
92 - 85%
84 - 78%
77 - 70%
<70%
100%
±50%
101 - 112%
113 - 125%
126 - 137%
138 - 150%
>150%
99 - 88%
87 - 75%
74 - 63%
62 - 50%
<50%
±10%
101 - 102%
103 - 105%
106 - 107%
108 - 110%
>110%
99 - 98%
97 - 95%
94 - 93%
92 - 90%
<90%
