Calibration procedure of O2-METER and CO2-METER
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Calibration procedure for LAMBDA OXYMETER (O2-Meter)
The O2 concentration can be calibrated on the LAMBDA OXYMETER (O2-Meter). The
calibration is a two-point calibration consisting of zero-setting and sensitivity setting:
Zero setting
Connect a source of nitrogen (N2) gas to the OXYMETER input barb. The gas flow rate
should be around 200 ml/min. Unplug the power supply and continuously press the
button located below the lowest order digit
of the display and reconnect the power
supply. The display shows
“NUL”
and a value, which is gradually stabilizing and
approaching zero. When the reading is stable, press button
P [mbar]
. The value of the
display is saved, the display shows
“0.00”
and the OXYMETER is switched to operation
mode. The saved value is subtracted from the value measured by the sensor, thus
correcting the zero setting. This correction applies to both parameters, the concentration
O2 [%] and the partial pressure O2 [mbar].
If you do not want to save this new zero setting, disconnect the power supply and
reconnect it again (without pressing any button). The zero value is now corrected by the
setting that was previously stored in the memory.
If you want to disable the zero setting, unplug the power supply and continuously press the
button located below the lowest order digit of the display and reconnect the power
supply. End the calibration mode by pressing simultaneously the buttons
T
[ºC]
and
O2
[mbar]
. By doing this the value zero is saved in the memory and the actual sensor
value is displayed in operation mode.
Sensitivity setting
Connect a source of air to the OXYMETER input barb. The gas flow rate should be around
200 ml/min. Press the
O2 [%]
button. The display will stabilize with the actual value of
oxygen concentration. After the actual value of oxygen concentration has stabilized the
correction factor can be calculated as the ratio between the real oxygen concentration
(e.g. 21.0 %) and the actual measured oxygen concentration.
Unplug the power supply and continuously press the
button located below the highest
order digit
of the display and reconnect the power supply. The display shows
“SLP”
and
then the value of the correction factor. Use the
buttons under the display to set the
desired value of the correction factor and press button
P [mbar]
. The correction factor is
saved, the display shows the actual O2 concentration and the OXYMETER is switched to
operation mode.