Hanna Instruments HI 84184 - Manual (Page 17)

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• The difference between the two recorded mV values gives the slope of the electrode. An
acceptable value for this slope is 56 ± 4mV.
• Press ESC to leave the reading check mode.
PERIODIC MAINTENANCE
Inspect the electrode and the cable. The cable used for connection to the instrument 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 deionized water.
Add filling solution dosing to maintain a good head pressure. For optimal electrode response this
level should be maintained and not be allowed to drop more than 2-3 cm (1 inch below fill hole).
STORAGE PROCEDURE
The HI 61010 sensor can be stored in standards for short periods of time and should be stored
dry with the protective cap on, when not in use, for long periods of time.
The HI 5315 reference electrode may be stored in air or aqueous solutions between sample
measurements.
If the electrode will be used frequently and needs to be ready for use, take measures to prevent
evaporation of fill solution. Top off fill solution, replace o-ring, fill hole cover on the fill hole
opening, and place protective cap over junction tip. Store the electrode upright. Before using,
flush junction once and top off fill solution.
For long term storage, disassemble electrode and wash all salts from assembly with deionized
water. Wrap ceramic junction on inner stern in Parafilm
TM or other sealing film. Store dry and
disassembled.
MALFUNCTIONING
Reading fluctuates or drifts:
Could be due to dirty or blocked reference electrode junction: follow the cleaning procedure
above. Repeat the measurement with a fresh potassium electrode.