f) Calibration
1.
Remove the protective probe cap. Press the
button (7) to switch the meter on.
2. Press the
button (3) to select O2 mode (oxygen). The “O2” symbol appears on the
LC display (8).
3. Wait ten to thirty minutes for the probe to polarise. The measured values must be at ap-
prox. 101.7 % saturation when the probe has been fully polarised. The value may not reach
101.7 % upon the first attempt at calibration. If the value reaches 85 %, you can calibrate
the probe at hand.
4. Leave the probe in the air . Press and hold the
button for approx. 3 seconds to start
calibration. The calibration symbol “CAL” (B) appears on the LC display and the saturation
value of 101.7 % starts to flash.
5.
The display stops flashing and displays “SA” followed by “End”. Calibration is complete. The
meter returns to “Measure” operating mode automatically.
6. Should calibration fail, the calibration error symbol (A) and “Err” appear instead of “SA”.
The operating mode with the “O2” symbol is intended only for calibration. The oxygen
content of the air cannot be measured.
1
Optional zero oxygen calibration
This setting improves the measurement accuracy when measuring very low or very high oxygen
contents.
1. Immerse the probe in an oxygen-free calibration solution such as 5 % sodium sulphite.
2. Leave the measuring probe in the solution. Wait until the value has stabilised.
3. Press and hold the
button (7) to invoke calibration.
4. A stable zero value in a zero solution may last for several minutes depending on the probe
history before calibration.
If the value displayed when the probe is not connected is not “0”, calibrate first in the
air without the probe in order to set the 0 % reading.
g) Taking measurements
1.
Remove the protective probe cap from the measuring probe.
2.
Rinse the measuring probe with distilled water before measuring and pat the probe dry.
3. Press the
button (7) to switch the meter on.
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