58 59
- Make sure cable and connections are not damaged nor
lying in a pool of water or solution.
• Slow Response/Excessive Drift: soak the tip in Hanna Solu-
tion HI 7061 for 30 minutes, rinse thoroughly in distilled
water and then follow the Cleaning Procedure above.
• For ORP Electrodes: polish the metal tip with a lightly abra-
sive paper (paying attention not to scratch the surface)
and wash thoroughly with water.
Note With industrial applications, it is always recommended to
keep at least one spare electrode handy. When anomalies
are not resolved with a simple maintenance, change the elec-
trode (and recalibrate the instrument) to see if the problem is
alleviated.
PERIODIC MAINTENANCE
Inspect the electrode and the cable. The cable used for the
connection to the controller must be intact and there must be
no points of broken insulation on the cable or cracks on the
electrode stem or bulb.
Connectors must be perfectly clean and dry. If any scratches
or cracks are present, replace the electrode. Rinse off any salt
deposits with water.
CLEANING PROCEDURE
General Soak in Hanna HI 7061 General Cleaning
Solution for approximately ½ hour.
Removal of films, dirt or deposits on the membrane/junction:
Protein Soak in Hanna HI 7073 Protein Cleaning So-
lution for 15 minutes.
Inorganic Soak in Hanna HI 7074 Inorganic Cleaning
Solution for 15 minutes.
Oil/grease Rinse with Hanna HI 7077 Oil and Fat Clean-
ing Solution.
IMPORTANT After performing any of the cleaning procedures rinse the
electrode thoroughly with distilled water and soak the elec-
trode in HI 70300 Storage Solution for at least 1 hour before
reinstalling it.
TROUBLESHOOTING
Evaluate your electrode performance based on the following.
• Noise (Readings fluctuate up and down) could be due to
clogged or dirty junction: refer to the Cleaning Procedure
above.
• Dry Membrane/Junction: soak in Storage Solution
HI 70300 for at least 1 hour. Check to make sure the
installation is such as to create a well for the electrode bulb
to constantly remain moist.
• Drifting: soak the electrode tip in warm Hanna Solution HI
7082 for one hour and rinse tip with distilled water.
• Low Slope: refer to the cleaning procedure above.
• No Slope:
- Check the electrode for cracks in glass stem or bulb
(replace the electrode if cracks are found).
