Xtralis VESDA-E VES-A10-P, Product Manual

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VESDA-E VES-A10-P Product Guide
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Term Description
O Obscuration The reduction in light transmission per meter or per foot due
to the presence of particulates.
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 that has an electrical contact which
can be configured to close when a condition occurs such as
fire alarm or a fault in the detector. This is the primary
method used to signal alarms and faults.
S Sampling Network The pipe network constructed to allow the VESDA-E
detector to draw air for sampling.
Sensitivity Sensitivity refers to sensitivity to smoke. A high sensitivity
denotes response to a lower concentration of smoke than a
low sensitivity.
Standby When the detector is in standby mode the aspirator is turned
off and the detector will not signal alarms via its relays. The
detector signals that it is in Standby mode using Relay 1.
Z Zone A defined area within the protected premises from which an
alarm signal can be received.
Table B-1: Glossary (continued...)