During Operation - Dräger X-AM 5000 Technical Manual

Operation
The presence of catalyst poisons in the measured gas (e.g., volatile silicone, sulfur,
heavy metal compounds or halogenated hydrocarbons) can damage the
DrägerSensor CatEx 125 PR. If the sensor cannot be calibrated to the target
concentration anymore, the sensor must be replaced.
The display of the CatEx sensor may be incorrect for measurements in a low-oxygen
atmosphere (<8 vol. % O
sensor is no longer possible.
In an oxygen enriched atmosphere (>21 vol. % O
cannot be guaranteed; switch off device or remove from the working area.

During operation

During operation, the measured values for every measured gas are displayed.
If a measuring range is exceeded or a negative drift occurs, the following displays are
shown instead of the measured value display:
» « (concentration too high) or
» « (measuring range not reached) or
» « (blocking alarm).
−
Excess concentrations of flammable materials can lead to a lack of oxygen.
−
For O concentrations below 8 vol. %, a fault is indicated for the Ex channel as
2
» « instead of the measurement, if the measurement is below the pre-alarm
threshold (not with setting CH4 with measuring range >100 %LEL).
In the event of an alarm, the corresponding displays, including the visual, audible and
vibration alarms, are activated – see "Identifying Alarms" on page 19.
If the measuring range is exceeded significantly on the CatEx channel (very high
concentration of flammable materials), a blocking alarm is triggered. This CatEx
blocking alarm can be acknowledged manually by switching the device off and back on
again in fresh air.
In configuration setting CH
triggered as the heat conductance measurement principle is used.
The measuring range 0 to 100 vol. % CH4 is not suitable for monitoring explosive
mixtures in the measuring range from 0 to 100%LEL.
When using a CatEx sensor in the Dräger X-am 5000, a calibration of zero point and
sensitivity must be carried out after an impact load that results in a fresh air display
not equal to zero.
After the measuring range of the TOX measuring channels has been exceeded tem-
porarily (up to one hour), checking the measuring channels is not necessary.
14
WARNING
); this means that reliable measurement with a CatEx
2
with measuring range 100 vol. %, no blocking alarm is
4
CAUTION
WARNING
), the electrical operational safety
2