Vision Systems VESDA, Руководство по конструкции

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Refrigerated Storage Design Guide
VESDA
®
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Sam pled Air Tem perature (deg C / F)
PE-100 Pip
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L
e
n
g
th
(m
)
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P
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-100 P
ip
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(ft)
20 l/m in
30 l/m in
40 l/m in
Figure 13 – Chart showing the estimated required PE-80/PE-100 pipe
extension for sampled air warming.
5.2 Heat Tracing
In extreme cases where there is no space to run pipe extensions or the external temperature varies
widely, heat tracing may be employed for sampled air warming. However, this approach to warming
sampled air is NOT recommended by Vision Fire & Security as it has not been validated by Factory
Mutual (FM).
Important Note: The Appendix contains information on the copper pipe and heat tape lengths
required for sampled air warming. No design guidelines will be given here. If wishing to use heat
tracing, appropriately qualified Engineers MUST be consulted as to the most suitable method to be
used.
5.3 Exhaust Air Treatment
Air from the VESDA exhaust pipe MUST be returned to the area from which it was sampled as
shown below (Figure 14).
Wall penetration
Ceiling Penetration.
Figure 14 – Examples of a VESDA exhaust pipe
being fed back into the area from which the air
sample was taken.
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