4.5
During operation
During operation, the measured values for every measured gas
are displayed.
In the event of an alarm, the corresponding displays, including the
visual, audible and vibration alarms, are activated, see chapter 4.6
on page 27.
If a measuring range is exceeded or not reached, the following
displays are shown instead of the measured value display:
»
« (measuring range exceeded) or
»
« (below measuring range) or
»
« (blocking alarm)
If an O
sensor is fitted and this sensor measures an O
2
concentration of below 12 vol.-%, an error is indicated with »
« on the ex-channel instead of a measured value if the measured
value is below the pre-alarm threshold.
After the measuring range of the TOX measuring channels has
been exceeded temporarily (up to one hour), checking the
measuring channels is not necessary.
NOTICE
i
i
Special states in which there is no measuring operation (quick
menu, calibration menu, warm-up of sensors, password
input) are indicated by a visual signal (slow flashing of the
alarm LED
Dräger X-am 2500
2
).
WARNING
!
If the DrägerSensor CatEx 125 PR is used in the gas detector,
a zero point and sensitivity 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.
Operation
!
2
27