147 Measuring with Galvanic Dissolved Oxygen (DO) Probes
Calibration Messages & Warnings
Message & Description Recommended Action
“Wrong Std”
The reading exceeds the expected
value. Calibration can not be confirmed.
Check that correct calibration
solution has been used and / or
clean the probe.
“Temperature Error”
The temperature of the solution is out of
temperature compensation interval.
Use fresh calibration solution and/or
clean the temperature sensor.
23.6. MAINTENANCE
23.6.1. Probe & Cap Membrane Cleaning
• Inspect, clean, and calibrate the probe at regular intervals.
• With the membrane cap assembled, rinse the probe with clean water. Blot the probe with a soft cloth or
tissue. Handle the probe and membrane carefully to avoid damage.
• Mechanical cleaning of the membrane with abrasives is not recommended.
•
Wipe probe's exterior with an aqueous soapy mixture. Gently rub persistent spots off. Rinse with clean water.
• Replace the membrane cap and electrolyte if coatings persists or membrane damage is evident.
23.6.2. Membrane Cap & Electrolyte Replacement
The membrane cap and electrolyte are designed to provide trouble‑free operation for about eight weeks.
Replacements are required when:
• The membrane cap is physically damaged
• Probe response is slow
• DO probe calibration or readings exhibit greater than normal drift
• The membrane cap remains coated after cleaning
Procedure
1. Remove the probe from installation.
2. Unscrew and remove electrolyte screw and fill hole O‑ring located on the side of the probe body.
3.
Hold the probe in a vertical position (sensing tip down) and unscrew the membrane cap. Discard used cap.
4. Remove the O‑ring off probe body and shake the probe down to empty the electrolyte reservoir.
5. Flush the probe body and reservoir with tap water.
6. Ensure the channel to the electrolyte reservoir is not clogged.
7. Gently clean the deposits off the zinc anode using a lint‑free cloth or tissue.
8. Inspect O‑rings for nicks or wear. Replace and discard damaged O‑ring.
9. If tarnished or stained, gently clean the silver cathode with a lint‑free cloth.
23.6.3. Long Term Storage
Discard any electrolyte solution from the reservoir, flush probe body and reservoir with water.
Blot the probe dry and store the probe with the protective cap on.
To Next Page
Loading...
