OPERATION OF AREARAE-Gamma
2-15
2.6 Alarm Signals
The built-in microprocessor continually updates and monitors
gas concentration levels. It also compares the readings with
programmed TWA, STEL, and Low & High instantaneous gas
concentration alarm limit settings. Whenever the concentration
exceeds any of the preset limits, the buzzer and red LED will
immediately warn the user the alarm condition. Additionally, the
AreaRAE-Gamma will alarm if one of the following conditions
occur:
•
Battery voltage falls below a pre-set voltage level (6.6V)
•
Failure of 10.6 eV or 11.7 eV UV lamp
•
LEL sensor is off
•
Pump
stalls
•
Datalog memory is full.
When the low battery alarm occurs, there will be approximately
20-30 minutes of operating time remaining before the monitor
automatically turns off as the battery voltage falls below 6.4 V.
Alarm Signal Disabled
It is extremely important to note that the alarm signals are
disabled during the following conditions:
•
PC communication standby mode
•
Calibration
mode.
During these modes of operation, real-time monitoring gas
concentration stops. None of the gas concentrations will be
calculated, including Peak, STEL and TWA values.
Alarm Signal Latching
It is possible to setup the AreaRAE-Gamma from a PC or while
user is in Program Mode so that when an alarm condition
occurs, the alarm signals remain on even after the alarm
condition is no longer present. This is called the “latching
alarm” mode. The alternative mode is to automatically reset the
alarm signal once the alarm condition is clear. The default
alarm mode is automatically reset (See Section 4.7.3 Change
Alarm Mode)
