Viking VSF303, Техническое руководство

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18 Safety and Technical Manual
Rev: 2
Form No. F_020521
VSF303 Flame Detector
This document is strictly private and confidential, reproduction without Viking Corporation approval is prohibited. © 2021 The Viking Group Inc.
Optical Contamination
There are many sources of contamination such as oil, water (deluge water, rain, and sea-spray),
snow, ice, and internal misting. Excessive contamination of the detector faceplate may result in an
increased maintenance requirement and potentially reduce the detector’s sensitivity. Where
detectors are mounted at low level, care should be taken to avoid contamination (such as water and
oil) from equipment above the detector. Care should be taken in sighting the detector to minimize
the likelihood of such contamination. The detector is designed such that an optical fault is generated
when half of the detection range remains. This is indicated by the fault output and is evident by the
yellow color of the LED on the face of the detector. The optical fault condition indicates that the
detector requires cleaning or service. The optical fault indication is self-clearing.
Enclosed Areas
In enclosed areas, if dense smoke is expected to accumulate at the onset of the fire, the detector
should be mounted 3 to 6 ft (1 to 2 m) below the ceiling level.
Detector Sensitivity
The detector’s response to a fire is a function of the fuel source and how it is released, fire size and
distance, orientation to the detector and local ambient conditions. The typical figures are based on
in-house tests except when marked with the FM logo, these tests were conducted and certified by
Factory Mutual. As with all tests the results must be interpreted according to the individual
application considering all possible variables.
The detector sensitivity to different fuel sources is dependent on the radiant heat output of the flame
and the detectors typical response is shown below (see table 4). The detector will only detect
hydrocarbon fires.
Detector Alarm Delay
The Detector can be factory configured with an Aux alarm delay (20mA) of between 0 and 10
seconds in 1 second steps over and above the normal response times of the 18mA alarm signal. If
the Aux alarm signal is delayed the 18mA alarm signal will precede the 20mA signal giving the
normal response times as tested by Factory Mutual to FM3260. The 20mA alarm signal if delayed is
considered an Aux alarm level.