Air Sampling Openings - Bosch FAS-420-TM Operation Manual

FAS-420-TM Aspirating Smoke Detector
During planning/design, a distinction is drawn between area monitoring and equipment
monitoring. For both applications, PVC pipes and halogen-free pipes can be used. The pipes
used for equipment monitoring should be halogen-free.
Figure 2.16 shows essential accessory components that can be selected for the application
concerned.
The pipe system must be constructed using pipes with an external diameter of 25 mm and the
associated fittings.
Blowing-out system
In areas that are susceptible to dust particles or icing, it may be necessary to blow out the
aspiration pipe system and its air sampling openings. Figure 2.17 shows a manual blowing-out
system with a three-way tap.
Figure 2.17 Components of manual blowing-out systems
2.6.2

Air Sampling Openings

Aspiration reducing film sheets
An air sampling opening is a 10 mm bore in the aspiration pipe that is covered with a patented
aspiration reducing film sheet with the required opening diameter. The size of the opening
depends on the structure of the pipe system (see Section 3 Planning, page 33).
The aspiration reducing film sheet is secured with marking tape to prevent it from becoming
displaced. The marking tape is a transparent sticky film with red edges and a 10 mm hole. It is
placed over the aspiration reducing film sheet so that the air sampling opening is not
concealed and can be seen from long distances.
Bosch Sicherheitssysteme GmbH
1
2
B
A
Operation Guide
Technical Specifications | en
A Blast air supply connection
B Pipe system connection
1 Three-way tap
2 25 mm aspiration pipe
Aspiration reducing clips
F.01U.088.878 | 4.1 | 2010.11
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