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BM 25A/AW
Instruction Manual
Unlatching Alarms
In this configuration, audible and visual alarms will be acknowledged automatically,
without any action, as long as the gas measurement is within the set limits.
Fault alarms
Faults can be classified into two categories:
■
Sensor faults: out of range, low sensitivity, zero drift, etc.
■
Monitor faults (low battery, wireless communication fault, electronics fault, etc.).
In the event of a fault, the monitor sounds a continuous audible alarm and the flash is
steady. The corresponding fault message appears at the bottom of the display.
Examples of information which may be brought to the user's attention
Battery fault
■
Low battery: remaining battery life is less than 20 minutes. The BM 25A/AW is still
operating, the audible signal can be silenced.
■
Battery fault: detection is no longer guaranteed. The audible signal cannot be
silenced.
> 100% LEL: Over-Range Flammable Gas Alarm Function
Applies to the combustible channel only. In this case:
■
Value on display is frozen.
■
Continuous audible signal cannot be silenced.
■
Visual flashlight is steady and cannot be turned off.
■
Combustible sensor (LEL) is powered down to prevent damages from
overexposure to gas.
Normal operating conditions can be restored by power cycling the BM 25A/AW. This
operation must be performed outside the hazardous area.
Out of range
■
Negative Zero Drift (reading below -20% of full scale). This fault is automatically
resettable.
■
Over-Range (reading above 120% of full scale). This fault must be acknowledged
manually.
Alarm transfer
The gas monitor features:
■
one alarm relay output monitored by any channel and dedicated to alarm transfer
■
one dry logic input to trigger the local alarm
Summary of Contents for BM 25A/AW
Page 1: ...BM 25A AW Area Gas Monitor Part Number NP25AEN Version C 4 User Manual ...
Page 10: ...10 BM 25A AW Instruction Manual Product Overview Figure 2 Product Overview ...
Page 18: ...18 BM 25A AW Instruction Manual ...
Page 34: ...34 BM 25A AW Instruction Manual ...
Page 70: ...70 BM 25A AW Instruction Manual ...
Page 75: ...9 Special Instructions 75 CSA Control Drawing for BM 25A AW Connections ...
Page 78: ...78 BM 25A AW Instruction Manual ...