User manual

Pico Technology DD103 DrDAQ Oxygen Sensor User Guide
DO091-2 2
4 Calibrating the oxygen sensor
Both PicoLog and PicoScope provide the facility to enter look-up tables. These
instructions will concentrate on doing so in PicoLog (for instructions on Custom
Ranges in PicoScope, see the PicoScope manual from the Help menu within the
application).
This is the information known so far:
Raw values (%)
Calibrated values known
to be true (%)
0 0
20.9 (known oxygen in air at
sea level)
Only one more value is needed to complete the look-up table; if you are measuring
the normal atmosphere then this reading is currently displayed on the PicoLog
monitor view. Complete the table above with this value and follow the instructions
below:
1. Select the Settings | Input channels menu item and click OK.
2. Select the oxygen sensor from the list then click Edit.
3. Click on Options, then Scaling.
4. From the drop down Scaling method menu, select Table lookup.
5. From the look-up table you completed above, enter these values in the
following format (replace 19.9 with whichever value you read from the
monitor view):
0 0
19.9 20.9
(Separate the values above with spaces)
6. Close all of the dialogs by clicking OK in each one.
PicoLog's monitor view should now display 20.9% (or very close) for the oxygen
content in air. If so, you've successfully calibrated your DrDAQ oxygen sensor. Save
your new calibrated settings for future use:
1. Open File | Save as...
2. Change the Save file as type: drop down menu to Settings files (*.pls)
3. Click OK to save the settings into a file name of your choice