Bosch FAD-420-HS-EN Duct Smoke Detector - Manual (Page 58)

58 en | Installation Duct Smoke Detector
F.01U.033.733 | 5.0 | 2011.11 Installation guide Bosch Sicherheitssysteme GmbH
4 Installation
4.1 Sample tube
Sample tubes must extend over the entire width of the
ventilation duct and are therefore available in three different
lengths:
– D344-1.5 (0.46 m/1.5 ft)
– D344-3 (0.91 m/3 ft)
– D344-5 (1.52 m/5 ft)
Sample tubes can be combined for wider ventilation ducts and
must be sealed with an end plug (see Figure 4.1). All sample
tubes have a locating pin threaded through and an end plug!
When combining two sample tubes, the end plug of the first
sample tube and the locating pin and locating screw of the
second sample tube must be removed!
Limits:
Steps for combining two sample tubes:
1. Remove the end plug from the first sample tube.
2. Remove the locating pin and locating screw from the
second sample tube.
3. Connect the two sample tubes.
4. Align the holes on the sample tubes and screw in the
locating screws.
5. Insert the end plug.
Example: You require a 2.13 m long sample tube.
Figure 4.1 Sample tube
No. Description
a Locating screw
b End plug
CAUTION!
A sample tube must have at least 12 extraction holes and be at
least 30 cm long. The maximum permissible length is 3 m!