Det-Tronics Eagle Quantum 95-8470-05, Инструкция по эксплуатации

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IV-3 95-8470
Different combinations of these variables allow for
various levels of transient arc rejection capability. There
are four arc rejection levels (very high, high, medium,
and low) that are selectable for each detector through
the PC. Refer to Table IV-2.
The proper arc rejection setting for a given application
must be determined through testing. For indoor
applications with known electrostatic energy fields
within 15 feet of the detector, an arc rejection setting of
“very high” or “high” is typical. For outdoor
applications, “medium” or “low” arc rejection settings
are typical.
It is recommended that each detector be thoroughly
tested at the programmed arc rejection setting within
the ambient conditions that will be present during
normal operation. This will help to ensure that the
selected arc rejection setting is proper for the
application.
Sensitivity
Whether the Standard or Arc Rejection mode is
selected, the sensitivity setting must always be
programmed. The selected sensitivity level determines
the fire alarm threshold setpoint. The higher the
sensitivity level, the greater the detection range, but the
possibility of false alarms will be increased. Four
sensitivity levels are selectable. Refer to Table IV-3.
The sensitivity setting must be appropriate for the
anticipated fire size at the required distance from the
detector.
Time Delay
Arc rejection mode — If the fire signal meets the
programmed arc rejection requirements, the time delay
begins. A fire output is generated if the fire signal
continues for the duration of the time delay.
Standard mode — A fire output is generated only if the
fire signal exceeds the sensitivity setting for the entire
duration of the programmed time delay.
Automatic or Manual
oi
The
oi
system uses an internally generated UV test
signal to determine the relative condition of the detector
and its optical surfaces.
If automatic
oi
testing is selected, the
oi
test is
automatically performed once every minute. The
automatic
oi
test does not generate an alarm output or
interfere with normal detector operation.
The manual
oi
test is initiated using a button on the
point display screen at the PC. The manual
oi
test can
be used in addition to automatic
oi
to verify correct
system operation.
Fire Output Latching
When latching operation is selected, the fire alarm
signal is cleared by removing input power for a
minimum of 0.1 second.
Arc Rejection Level Consecutive Gates Gate Length Sensitivity* Min. Processing Time
Very High 8 1/16 Second Very High (8 CPS) 0.5 Second
High 4 1/16 Second Very High (8 CPS) 0.25 Second
Medium 4 1/8 Second Very High (8 CPS) 0.5 Second
Low 4 1/4 Second Very High (8 CPS) 1.0 Second
T0006A
* CPS = counts per second
Table IV–2—Arc Rejection Levels for UV Detector
Sensitivity Level Equivalents
Sensitivity Level Selected Nominal Fire Alarm Threshold
In Counts per Second (CPS)
Very High 8
High 24
Medium 48
Low 96
T0007A
Table IV–3—Sensitivity Levels for UV Detector