VESDA VLI Product Guide
VESDA by Xtralis
72
www.xtralis.com
Term
Description
R
Referencing
Referencing is a technique used to reduce false alarms. It
requires VESDAnet.
A separate detector takes readings of the background level
of smoke and pollutants outside of the protected area. These
readings are then referenced to the readings from the
detectors in the protected area. This allows the internal
detectors to determine if a rise in smoke levels is due to
background pollution or a problem inside the protected area.
Relay
A device on a detector which allows external equipment to
be hard wired to it and be triggered when various conditions
occur (example, sounding a siren at Alert threshold).
S
Sampling Network
The pipe network constructed to allow the VESDA detector
to draw air for sampling.
Sensitivity
Degree of response (i.e. activation of alarm condition) of a
detector. A high sensitivity denotes response to a lower
concentration of smoke than a low sensitivity.
Z
Zone
A defined area within the protected premises from which an
alarm signal can be received.
Table B-1: Glossary (continued...)