H59.0.21.6C-11
page 5 of 8
7
Oxygen measuring
The oxygen measurement
depends on air pressure
. The current pressure can be
entered during configuration.
If you
measure at atmosphere
and the calibration took place at the same
conditions, the pressure value has not to be adjusted necessarily, because the
same pressure is used for calibration and measuring.
If the measurement is carried out at
other pressure conditions
than the
calibration: The actual pressure has to be entered in the configuration for
measurement and calibration.
T
he sensor’s
temperature dependency
is compensated internally. However for
best results try to keep the same temperature both during calibration and
measuring.
Temperature differences between sensor and gas
may cause additional errors!
Therefore wait an appropriate period of time until the sensor has adjusted its
temperature to the gas that is measured. A suitable flow of the gas around the
sensor increases the adjustment significantly.
Try to avoid warming of the sensor by touching it during measurement or
calibration.
When
measuring bottled gas
, consider that the gas coming out is cooler than the
ambient because of the pressure loss! Strong air flows can produce an over
pressure at the sensor
– possible source of measuring/calibration errors!
The nominal life time can be shortened by:
-
Wrong storage / operation temperature
-
Permanent use with dry gases (compressed gas).
It helps to put the sensor to normal-humid ambient air in measuring breaks
(“flush” system with fresh air).
The
optimum operation position
is: with the sensor inlet pointing downwards
8
Calibration
In order to compensate for ageing of the sensor and air pressure fluctuations due
to weather changes, the sensor has to be calibrated at regular intervals. We
recommend to calibrate it at least once a week or, for optimum measuring results,
directly before starting the measuring process. Adjust the absolute pressure at the
configuration point “P.Ab” before carrying out a calibration.
Calibration:
The sensor will be calibrated to the atmospheric oxygen concentration
of 20.95%
.
The sensor has to be subjected to air (make sure that rooms are
thoroughly aired).
Press the
key for 2 sec till
appears.
The calibration will be automatically completed as soon as the measuring values
for oxygen are stable (takes a few seconds). After the calibration the device will
show the rating of the sensor state for a short time.
If an error message (CE.3, CE.4, CE.6) is displayed, the sensor signal is
invalid. Press any key to restart, the previous calibration will be restored.
