16
Automatic Calibration in Air
The slope is corrected using the saturation value (100 %), similar to air satu-
ration of water. Since this analogy only applies to water-vapor saturated air
(100 % relative humidity) and often the calibration air is less humid, the relative
humidity of the calibration air must also be specified. If you do not know the
exact value of the relative humidity of the calibration air, you can take the fol-
lowing reference values for a sufficiently precise calibration:
• Ambient air: 50 % rel. humidity (average)
• Bottled gas (synthetic air): 0 % rel. humidity
NOTICE!
The sensor membrane must be dry. Be sure to keep temperature and pres-
sure constant during calibration. If there is a temperature difference between
calibration medium and measured medium, you must keep the sensor in the
respective medium for several minutes before and after calibration.
Menu Display
Selecting a calibration mode
Select module:
The module is in func-
tion check (HOLD) mode. The assigned
current outputs and relay contacts
behave as configured (BASE).
Press
enter
to confirm.
Select “Automatic - Air” calibration
method
Remove sensor and place it in air.
Press
enter
to confirm.
Calibration
Return
25.6°C
Module PH 3400-035
Module CONDI 3400-051
Info
80.3%Air
Module LDO 3400-170
Module LDO 3400-170
Return
25.6°C
Product calibration Sat
Zero correction
80.3%Air
Automatic - Water
Automatic - Air
Calibration / Adjustment
Automatic Calibration in Air
N
ot
e:
T
he displa
y ma
y v
ar
y depending on the devic
e v
ersion.