Bosch FAS-420-TM, Operation Manual

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FAS-420-TM Aspirating Smoke Detector Planning | en 37
Bosch Sicherheitssysteme GmbH Operation Guide F.01U.088.878 | 4.1 | 2010.11
3.4 Defining the Response Sensitivity
The sensitivity of smoke aspiration systems can be divided into certain fire sensitivity classes
in accordance with EN 54-20. These fire sensitivity classes describe specific examples of ways
in which the systems can be applied. The permissible system plans given in 3.6 can be
determined for each classification.Smoke aspiration systems with a higher fire sensitivity
class according to EN 54-20 also satisfy the requirements of the lower classes.
The table shows the sensitivities you can choose from
The planning of the monitoring area always occurs according to the national guidelines for
point-type smoke detectors.
NOTICE!
As an air-return pipe needs to be provided when the FAS-420-TM series is used in areas with
varying air pressures, and given that no air-return pipe is possible with ROOM·IDENT, it is not
possible to use the FAS-420-TM series with ROOM·IDENT in areas with varying or fluctuating
air pressures.
Class Description Application example
A Aspirating smoke detector with
extremely high sensitivity
Very early detection: significant smoke
dilution through air conditioning in IT
areas
B Aspirating smoke detector with
increased sensitivity
Early detection:
significant time gains thanks to very
early fire detection (without air
condition)
C Smoke aspiration system with normal
sensitivity
Normal detection:
fire detection with the advantages of
smoke aspiration systems
NOTICE!
Depending on the number of air sampling openings, fire sensitivity classes A, B and C can all
be achieved with the detector modules available.
Sensitivity Standard sensitivity FAS-ASD-DIAG
settings intervals
Detector module 0.5 - 2%/m 0.5%/m 0.1 %/m