Oldham BM25, Руководство по эксплуатации

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Faults concerning sensors: out of range, worn sensors, request for calibration in the case
of a major deviation during auto-adjustment. These faults generate messages on the
display unit, a visual alarm (steady red light) and a steady audible alarm.
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Faults concerning the instrument itself (discharged batteries or electronic fault). The
corresponding fault message appears at the bottom of the display unit. It takes priority
over all other sensor-related messages.
Examples of information which may be brought to the user's attention
v
Battery pre -alarm warning
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The remaining battery life is at least 20 minutes, during this phase, measurements are still
provided, only audible beep can be acknowledged.
•
Battery fault : The BM25 is no longer measuring, fault is not acknowledgeable.
v
" > 100% LEL: outside range" in explosive channel
This concerns only the explosive channe l and if there is no catharometric sensor ( 0 to 100%
vol).
In this case:
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the display of the channel concerned is frozen
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it is impossible to acknowledge the continuous audio signal
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the general alarm indicator lights come on in steady mode
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power to the exp losive gas sensor (LEL) is cut off for its protection
Normal operating conditions can be restored by stopping and restarting the BM25 gas
detector (this operation must be performed outside the hazardous area)
v
“Outside range” for toxic gas and oxygen
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negative fault (reading below -20% of the scale), acknowledged automatically
•
positive fault (scale exceeded by 120%), must be manually acknowledged.
7.3. Acknowledging gas alarms
7.3.1. Manually acknowledging gas alarms
Pressing the “Acknowledge” button stops the audible alarm, but the alarm indicator light flashes
until the measurement is lower than the programmed alarm threshold. As soon as the measurement
returns within the defined limits, the visual signal is automatically stopped.
In standard configurations, the audible alarm will be reactivated after 2 minutes if the gas level is
still above pre-defined limit(s) (this feature can be disengaged by request).
7.3.2. Acknowledging alarms automatically
By request, it is possible to automatically stop gas alarms as soon as the concerned gas levels
exceed the pre-defined threshold without pressing the “Acknowledge” button.