Design
TITANUS
RACK·SENS
®
1U
4 –
14
Data: 03/09
TRS_A_04-en-e
4.4 General pipe system project planning
4.4.1 Pipe system configurations
When planning the pipe system, it must be ensured that reliable fire dete-
ction is guaranteed for any fire present in an installation or in a monitored
area.
The number of sampling holes and the pipe system layout depends on
the size, ventilation and shape of the monitored area. The pipe system is
to be fitted in accordance with the project planning guidelines in this sec-
tion while taking into consideration the following points:
S
ymmetrical design
The pipe system shall preferably be designed to be symmetrical, i.e.:
z
equal number of sampling holes per pipe branch
z
equal lengths of pipeline (must not exceed ± 30 % deviation)
z
Equal distances between adjacent sampling holes in sampling pipe
(do not exceed deviation of ±30%)
z
Similar air pressure conditions along the sampling pipe
z
If air outlets located at cabinet doors are to be monitored, then it is ad-
vised to use short, flexible tube interconnections (max. length 30 cm)
z
The pipe system is should be constructed with rigged pipe. Flexible
tube interconnections are only to be used as an exception. This is due
to possible air flow changes once the tube is moved.
z
Please keep the length of tube interconnections as short as possible.
Asymmetrical design
If the pipe system must be laid out asymmetrically due to structural con-
straints, the following specifications apply:
z
The number of sampling holes as well as the length of the shortest
and longest pipe branch in the pipe system must not exceed a quantity
or length ratio of
1:2
.
z
The distances between adjacent sampling holes in the sampling pipe
must be equal (do not exceed deviation of ±20%).
z
The diameters of the sampling vents are determined for each pipeline
branch individually and depend on the number of sampling vents on
the pipeline branch in question.
Branch
length
In order to ensure that smoke aerosols are transported quickly through
the sampling pipe and to ensure fast detection, it is better to plan several
shorter branches than a few long ones (preferably a “double U-shape pi-
pe system” instead of a “I or U shape pipe system”).
