Incite Fire ASD 532, Operating Manual

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Function
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2.2.2 Fan control
The physical and electrical properties of a fan cause a brief power surge when it is switched on and starts up, which in turn af-
fects the conductor dimensioning and the total power consumption of the fire alarm system.
A specially designed circuit therefore ensures that the fan cannot exceed a specific maximum power consumption in its start-
up phase. When the ASD 532 is switched on, the computer-controlled fan speed starts up slowly. After the fan has been pow-
ered up, the speed is kept constant.
Any blocking of the fan is detected by evaluating the motor speed. If the specified threshold is undershot, the fan supply is
switched off and a fault is signalled.
Depending on the size of the system and/or environment, the fan can be operated at different speeds (by means of the
“ASD Config” configuration software). This is useful primarily in critical areas (long pipes) to increase the transport speed in the
sampling pipe tube network (high speed) or to reduce the noise level in cases where the noise level produced by the fan is a
disturbance (low speed). The following fan speed levels can be selected:
Level
Speed
(rpm)
Effect
I 5250 Low transport speed / low noise level
II 6900 Normal transport speed / reduced noise level
III 9300 High transport speed / normal noise level
Notice
•
The fan speed levels can be changed only with the “ASD Config” configuration software.
•
For applications and commissioning without “ASD Config” configuration software, Level II must always set.
•
If the fan speed is changed (by using the “ASD PipeFlow” calculation software), ensure that the maximum
permissible transport time according to EN 54-20 is not exceeded.
•
After the fan speed has been changed, it is imperative that a new initial reset is carried out (observe waiting
time of at least 2 min).
2.2.3 Microcontroller
The entire program and switching sequence is controlled by a microcontroller. The firmware is stored on a Flash PROM . Sys-
tem-specific configurations are stored in an EEPROM.
The program is monitored by the internal watchdog of the microcontroller. In the event of a failure of the microcontroller circuit,
an emergency fault is triggered. This is signalled on the device by the steady lit
Fault LED. The “Fault” relay switches.
ASD532 Operating Manual