Sper Scientific 850045 Dissolved Oxygen - DO Pen - Manual (Page 7)

MEASUREMENT PROCEDURES
7
Dissolved Oxygen (DO) Measurement
1. Make certain the meter has been calibrated (page 5).
2. Press and hold the Unit button (Fig., 1-3) for at least 2
seconds, the display will change from %O
2
to mg/L.
3. The meter is now ready to measure.
4. To activate Automatic Temperature Compensation the
probe head (Fig., 1-5) must be immersed to a depth of
10cm. It takes several minutes for the temperature of
the probe and liquid to equalize.
5. For accurate D.O. measurement of any liquid, the probe
should be moving. Make sure that the velocity of the
movement is at least 0.2 - 0.3 m/s. This can be achieved
by shaking the probe.
Note...
To keep errors to a minimum during laboratory
measurements, use of a magnetic agitator is
recommended.
6. Rinse the probe with tap water after each measurement.
7. Re-install the probe head’s protector cover (Fig., 1-7).