12
MW190
Bench Meter
8. D.O. MEASUREMENTS
Make sure that the instrument has been calibrated and the protective cap has been
removed.
y
Immerse the tip of the probe in the sample to be tested. Allow
approximately one minute for the reading to stabilize.
y
The Dissolved Oxygen value (in %) is displayed on the primary LCD and the temperature
on the secondary LCD.
y
Press RANGE to change the reading from % to ppm and vice-versa.
For accurate Dissolved Oxygen measurements, a water movement of 0.3 m/s is required.
This is to ensure that the oxygen-depleted membrane surface is constantly replenished.
A moving stream will provide adequate circulation.
The use of a magnetic stirrer to ensure a certain fluid velocity is recommended.
9. TEMPERATURE MEASUREMENTS
The probe has a built-in temperature sensor.
The measured temperature is indicated on the secondary LCD as shown above.
Allow the probe to reach thermal equilibrium before taking any measurement. This can
take several minutes. The greater the difference between the temperature at which the
probe was stored and the temperature of the sample, the longer the time will be.
Note: If “----” is displayed, the D.O. probe is not properly connected or the temperature
is out of range. This also indicates the posibility of a broken probe cable.
