Det-Tronics X5200 UVIR Flame Detector - Manual (Page 6)

95-8546 4 13.1
Quick Fire (High speed)
The Quick Fire (High Speed) feature can be used in
conjunction with the TDSA signal processing method.
This method overrides TDSA requirements in the event
of a sudden and intense signal, such as the result of a
flash fire. When Quick Fire is activated, the detector is
capable of responding to an intense fire signal in less
than 30 milliseconds (0.030 seconds). Using the Quick
Fire feature in conjunction with TDSA signal processing
allows the detector to provide a high speed response to
a large, non-flickering fire (such as in high pressure gas
applications). Additionally, when the Quick Fire feature
and TDSA signal processing are used in conjunction, the
detector maintains an ability to respond to fires that start
very small and grow in size and intensity over time.
uV DETECTOR OpTIONs
The UV detector output (measured in counts per second)
is compared to the fire threshold (the “sensitivity”
setting). If the radiant energy level from the fire exceeds
the selected alarm threshold level, the fire alarm output is
activated. In every application, it is crucial to ensure that
the radiant ultraviolet energy level from the expected fire
at the required distance from the detector will exceed the
selected sensitivity level.
The UV detector in the X5200 can be programmed for:
– Arc Rejection
– Standard Signal Processing
Arc Rejection
The Arc Rejection mode enables the detector to
prevent nuisance fire alarms caused by UV from short-
duration electrical arcs or electrostatic discharge, while
maintaining the ability to reliably detect the UV radiation
given off by a flame. Typical applications that benefit
from arc rejection logic include electrostatic coating
processes and uncontrolled environments where
transient UV sources can be present, such as many
typical outdoor applications. Most false alarm sources
have short transient UV signatures, while fire creates
a long UV signature over many seconds. Most fires
are detected in a few seconds (see response times in
Appendix A).
standard signal processing
Standard signal processing is recommended for high-
speed suppression systems only. To allow for high-speed
operation, the standard processing mode does not
incorporate the arc rejection programming. This mode
should only be used in a controlled, indoor environment.
gENERal aPPlICaTION
INfORmaTION
REspONsE CHARACTERIsTICs
Response is dependent on the detector's sensitivity
setting, arc rejection, and time delay settings. Other
factors include distance, type of fuel, temperature of the
fuel, and time required for the fire to come to equilibrium.
As with all fire tests, results must be interpreted according
to an individual application.
See Appendix A for third-party approved fire test results.
Additional fire test results are available from Det-Tronics.
Welding
Electric arc welding is a source of intense ultraviolet
radiation. UV radiation from arc welding readily scatters
and can deflect across significant distances, even when
direct obstructions exist. Any open door or window can
allow nuisance UV radiation from arc welding to enter an
enclosed area, causing a possible response from the UV
detector.
It is recommended that the system be bypassed during
welding operations in situations where the possibility of a
false alarm cannot be tolerated. Gas welding mandates
system bypass, since the gas torch is an actual fire. Arc
welding rods can contain organic binder materials in
the flux that burn during the welding operation and are
detectable by the X5200. Welding rods with clay binders
do not burn and will not be detected by the X5200.
However, system bypass is always recommended, since
the material being welded may be contaminated with
organic substances (paint, oil, etc.) that will burn and
possibly cause the X5200 to alarm.
Artificial Lighting
The X5200 should not be located within 3 feet (0.9 m)
of artificial lights. Excess heating of the detector could
occur due to heat radiating from the lights.
EMI/RFI Interference
The X5200 is resistant to interference by EMI and RFI,
and is EMC Directive compliant and CE marked. It will
not respond to a 5 watt walkie-talkie at distances greater
than 1 foot (0.3 m).
Non-Carbon Fires
The response of the X5200 is limited to carbonaceous
fuels. It should not be used to detect fires from fuels
that do not contain carbon, such as hydrogen, sulfur and
burning metals.