VESDA by Xtralis
VESDA VLF-500 Product Guide
www.xtralis.com
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Sampling Pipe Network Design
The VESDA VLF supports a number of pre-engineered pipe network designs to simplify installation. The pre-
engineered pipe networks have been designed with pressure, flow and transport time considerations. They
have been verified and are shown below. For setup details refer to the VESDA System Design Manual.
The pre-engineered designs assume the following constraints:
1. There must be no mixing of open hole and capillary tubes in a pipe network design. All sampling points
must be of the same type.
2. All sampling points must be evenly spaced in a pipe network design.
3. Branched designs must use the same number of sampling points along each branch.
4. Open hole designs must use the same size hole throughout the design.
5. Capillary tube designs must use the same size and length of capillary tube throughout the design.
6. The distance from the detector to the first sampling point must be 1 to 2 times the distance between
sampling points. For example, if the sampling points are 4 meters apart, then the distance from the
detector to the first sampling point must be between 4 and 8 meters.
Given the constraints detailed above, the pre-engineered pipe network designs will provide:
Parameter
Value
Transport times
less than 60 seconds for open holes
less than 90 seconds for capillary tubes
Suction pressure
greater than or equal to 25 Pa across holes and
capillary tubes
Detector pressure
greater than 70 Pa
Flow rate
12 - 54 L/min
For alternate or complex pipe network designs including end caps with sampling holes use the ASPIRE pipe
modeling software to verify pipe performance. For code-specific information, refer to Codes and Standards
Information for Air Sampling Smoke Detection on page iii.
