Dräger X-am 3500 Notice D'utilisation page 38

en |
Maintenance
● For a span calibration of Dräger IR sensors, it is assumed
that a valid zero-point calibration exists (no more than
30 min. old), otherwise an acknowledgeable warning is
displayed.
Calibration may not be possible due to instrument and
channel errors.
5.5.1 Fresh air calibration
To improve accuracy, a fresh air calibration must be carried
out if a zero deviation exists.
Observe the following notices for the calibration:
● For the fresh air calibration of Dräger IR sensors for
explosive hydrocarbon, it is assumed that the change in
the zero-point leads to a change of less than or equal to
±5 %LEL of the measured value at 50 %LEL. If the
deviation is greater than ±5 %LEL, the span calibration is
invalid.
● For the fresh air calibration, the display on the XXS O
and XXS O PR is set to 20.9 Vol%.
2
Requirements:
– Fresh air calibration can only be carried out if at least one
sensor supports the fresh air calibration.
– The fresh air must be free of measured or interfering
gases.
– The gas detector is switched on and warm-up phases 1
and 2 are complete.
To carry out a fresh air calibration:
1. Switch on the gas detector.
2. Call up the fresh air calibration (depending on the
configuration):
If the fresh air calibration was released for user level 0 by
the Dräger CC-Vision PC software:
● Select > Maintenance > Fresh air cal..
If the fresh air calibration was not released for user level 0
by the Dräger CC-Vision PC software:
a. > Login
b. Enter and confirm the password.
c. Select Maintenance > Fresh air cal..
3. Select to start the fresh air calibration.
 All measuring channels which are included in the fresh
air calibration flash, and all others are greyed out.
The result is displayed as follows for every measuring
channel:
fresh air calibration successful.
fresh air calibration failed.
4. If necessary, press
this case, a calibration takes place immediately.
Dräger recommends using the automatic stability
control (wait until the gas detector has automatically
carried out the calibration).
 The new measured value is displayed for control
purposes.
The result is displayed as follows:
fresh air calibration successful.
fresh air calibration failed.
38
to overrule the stability control. In
5. The fresh air calibration is complete when all participating
measurement channels have passed or failed the fresh air
calibration.
● Select and then confirm the dialog to discard the
result.
● Select to confirm the result.
If there was an error during the fresh air calibration:
– Repeat the fresh air calibration.
– If necessary, replace the sensor.
5.5.2 Carrying out a single-gas calibration
Observe the following notices for the single-gas calibration:
● For a single-gas calibration, you can choose either the
zero-point calibration and span calibration.
● With a zero-point calibration, the zero-point of the selected
sensor is set to zero.
● For the zero-point calibration of Dräger IR sensors, it is
2
assumed that the change in the zero-point leads to a
change of less than or equal to ±5 %LEL or 0.05 Vol%
CO of the measured value at 50 %LEL or 0.5 Vol% CO
2
If the deviation is greater than ±5 %LEL or 0.05 Vol% CO
the span calibration is invalid and an error or a warning is
displayed (configurable).
● For a span calibration of Dräger IR sensors, it is assumed
that a valid zero-point calibration exists (no more than
30 min. old), otherwise an acknowledgeable warning is
displayed.
● For a span calibration, the sensitivity of the selected
sensor is set to the concentration value of the test gas.
Use a standard test gas.
Allowed test gas concentration:
2 1)
DUAL IR CO (ES)
2 1)
IR CO (ES)
1)
DUAL IR Ex (ES)
1)
IR Ex (ES)
CatEx
O , O PR
2 2
H S
2
1)
H HC
2
Dual IR Ex/CO HC
2
1)
(CO channel)
2
1)
PID HC
1)
PID LC ppb
Test gas concentration of other gasses:
Refer to the Dräger CC-Vision PC software
1) X-am 8000 only
2) Depending on the measuring range and the measuring accuracy.
Dräger recommends selecting a test concentration in the
middle of the respective measuring range or close to the
expected measuring range.
2)
0.05 to 5 Vol%
The permissible test gas con-
centrations were displayed
by the gas detector for the
single-gas calibration of the
sensitivity.
20 to 80 Vol%
100 ppm iBut
5 ppm iBut
Instructions for use |
X-am
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2
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2
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3500