Operation
WARNING
!
If the DrägerSensor CatEx 125 PR is used in the gas detector,
a zero point and span calibration must be carried out after
experiencing an impact load that results in a non-zero display
when exposed to fresh air. This warning does not apply if the
DrägerSensor CatEx 125 PR Gas is used.
4.6
Identifying alarms
An alarm is displayed visually, audibly and through vibration in a
specific pattern.
NOTICE
i
i
At low temperatures the legibility of the display can be
improved by switching on the backlight.
4.6.1
Concentration pre-alarm A1
Intermittent alarm:
Alternating display of A1 and measured value. Not for O
The pre-alarm A1 is not latching and stops when the concentration
has dropped below the alarm threshold A1.
In case of A1, a single tone is audible and the alarm LED flashes.
In case of A2, a double tone is audible and the alarm LED flashes
twice.
Acknowledge pre-alarm: Press the OK key. Only the audible alarm
and the vibration alarm are switched off.
26
4.6.2
Concentration main alarm A2
WARNING
!
Risk of fatal injury! Leave the area immediately. A main alarm
is self-retaining and cannot be acknowledged or cancelled.
Intermittent alarm:
Alternating display of A2 and measured value.
For O
:
A1 = lack of oxygen
2
A2 = excess oxygen
After leaving the area, when the concentration has dropped below the
alarm threshold:
Press the OK key. The alarm messages are switched off.
If the measuring range is exceeded significantly at the CatEx channel
(very high concentration of flammable materials), a blocking alarm is
triggered. This CatEx blocking alarm can be manually acknowledged
by switching the instrument off and on in fresh air.
!
2
Dräger X-am 2500