OPERATION OF MULTIRAE PLUS
2 - 17
2.5 Alarm Signals
The built-in microcomputer updates the gas concentrations
every second and compares them with the programmed
alarm limits (TWA, STEL, and two instantaneous gas
concentration alarm limit settings: Low & High).
Whenever the concentration exceeds the sensors’ preset
limits, the loud buzzer and red flashing LED are activated
immediately to warn the user of the alarm condition.
In addition, the MultiRAE PLUS will alarm if one of the
following conditions occurs: battery voltage falls below a
pre-set level (4.4 V), failure of the UV lamp, LEL sensor
off, pump stall or when the datalog memory is full. When
the low battery alarm occurs, there will be approximately
20-30 minutes of operating time remaining. When the
battery voltage falls below 4.2 V, the monitor will be turned
off automatically.
Alarm Signal Disabled: It is extremely important to
note that during the following conditions, the alarm
signals are disabled:
1) In PC communication standby mode.
2) In calibration mode (including reviewing datalog
data).
During these modes of operation, real time monitoring of
the gas concentration stops. None of the gas concentrations
will be calculated, including Peak, STEL and TWA.
