Sensor Maintenance - Lovibond SD 310 Oxi Mode D'emploi

7.3 Sensor maintenance

If it is not possible to calibrate the sensor or it only produces instable measurement values, it
has to be serviced or the membrane cap must be replaced.
Maintenance is carried out in the same way as the initial filling procedure.
First unscrew the membrane cap and remove the old electrolyte.
Unscrew the membrane head and wipe off the electrolyte solution carefully using a paper towel.
Attention: Old electrolyte will leak out!
If the membrane is undamaged, the membrane head can be re-used. Otherwise the membrane
head must be replaced.
8. Instructions for oxygen measurement
The following should be taken into account when measuring dissolved oxygen:
•
Remove the storage flask prior to the measurement.
•
The sensor must have been calibrated first.
•
The sensor and the liquid to be measured must be at the same temperature (compare
temperatures)
•
The sensor must be immersed at least 3 cm into the liquid to be measured
•
Measurements are only sufficiently accurate with a minimum flow velocity of approx. 30
cm/sec: This is done by permanently stirring the liquid or using an appropriate stirring
device!
•
The measurement is sensitive to shock!
For this reason, it is important to make sure when stirring the liquid that the sensor does not
bang against the container which could otherwise significantly affect the measurement value.
- The optimum operating position is when the sensor opening is facing downwards.
The oxygen's partial pressure, the oxygen concentration [mg/l] and the oxygen saturation [%]
is calculated from the sensor signal and temperature. The measurement is based on water
vapor-saturated air in accordance with DIN38408-C22.
44 SD_310_2 07/2018