Dräger Flame 2350 Instructions For Use Manual page 7

2.2.3 Dräger Flame 2370
The flame detector is a dual spectrum optical detector. It provides a
combination of UV and IR sensors that measure the radiation intensity
within two ranges of the UV and the IR electromagnetic spectrum.
The flame detector monitors two
detection pulses are registered and further analyzed for frequency,
intensity and duration.
The flame detector features a highspeed response time of less than
20 milliseconds.
Sensing elements
The UV sensor is sensitive to radiation over the range of 0.185-
0.260 µm. The UV channel incorporates a special logic circuit that
eliminates false alarms caused by solar radiation and other non-fire
UV sources. Furthermore, the sensitivity of the UV channel is
stabilized over the working temperature range.
The IR sensor of the flame detector is sensitive to radiation over a
range of 2.5-3.0 µm where the H
peak that enables detection of hydrocarbon fires, gas fires, hydroxyl
and hydrogen fires as well as metal and inorganic fires.
Detection levels
Simultaneous detection of radiation in both the UV and the IR channels
having an intensity that exceeds the preset warning level results in a
warning signal.
Simultaneous detection of radiation in both the UV and the IR channels
having an intensity that exceeds the preset alarm level results in an
alarm signal.
Simultaneous detection of radiation in both the UV and the IR channels
having an intensity that exceeds the preset flash-fire detection level
results in an immediate alarm signal without any delay.
Since the preset dual range and level of radiation, as well as the
flickering pattern, are characteristics of real fire, all other radiation
sources apart from actual fire are not detected, thus avoiding false
alarms.
channels in which appropriate
O emission has a unique spectral
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2.2.4 General
The flame detector includes a heated optical window. The heater
increases the temperature of the optical surface by 3-5 °C (5-8 °F)
above the ambient temperature to improve performance in icing, snow,
and condensation conditions.
The flame detector is available in 5 wiring options. The wiring options
are defined at the factory per customer order and cannot be changed
at the customer facility. For more information, please refer to
chapter 7.2 on page 21.
Alarms are set as non-latching by default. However, the flame detector
includes a latched alarm output capability, which operates according to
the programmed function. Latching affects alarm relay, auxiliary relay,
0-20 mA output, and status LED. If selected, upon detection of a fire,
the detection signal is latched until a manual reset is performed (see
chapter 3.4.2 on page 18).
Detection performance can be easily adapted to all environments,
applications, and requirements by changing the configuration
parameters of the flame
communication (all models) or HART communication (in models with
0-20 mA output) can be used to change the configuration parameters
or perform monitoring or maintenance tasks. For more information on
communication, please refer to chapter 3.3.7 on page 14.
The detector is designed to withstand harsh environment conditions
(for example extreme temperatures, high humidity and vibrations).
If several flame detectors are used in automatic fire detection systems,
one flame detector may be equipped with a built-in end-of-line (EOL)
resistor per customer order. The resistor is available with 10 different
values. It depends on the control unit, which resistor value is required.
For more information, please refer to chapter 3.1 on page 11.
Description
detector. RS-485-based Modbus
en
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