Use and maintenance of dissolved oxygen meter
1. Before using the instrument, connect the voltage regulator and battery.
When a newly purchased instrument is not used for a long time, electrolyte should be added to the electrode (otherwise the dissolved oxygen value cannot be measured).
3. Pull the electrode sheath backwards, insert the oxygen electrode, and ensure that the plug is in good contact with the socket (hear a click). Polarize with electricity for 5 minutes.
4. Zero oxygen calibration: Place the electrode in a 5% sodium sulfite solution, and the closer the displayed value is to zero, the better. Full air calibration: display the corresponding saturated dissolved oxygen value at the current temperature. If there is a significant difference, the zero oxygen and full scale calibration can be repeated.
5. The instrument should be regularly calibrated and replaced with electrolyte and membrane to ensure measurement accuracy. If the instrument is frequently used, it is recommended to calibrate it every 10 days. When installing the film, it is necessary to ensure complete contact between the film and the gold surface, otherwise it may not be removed under zero oxygen, or the values may be inaccurate or unstable during the measurement process.
6. If dissolved oxygen electrodes are used for a long time, especially after continuously measuring sewage, the silver electrode inside the electrode will turn black and oxidize. At this time, it is necessary to regularly replace the electrolyte and film, and clean the surface of the silver electrode and the gold surface. If all indicators are not ideal, consider purchasing new electrodes.
7. Dissolved oxygen electrodes can be stored in distilled water when not in use. When the instrument is not in use for a long time, the battery should be removed.
During sampling and measurement, the electrode should move relative to the solution and should not be stationary (slowly stirred).
