Hanna Instruments HI 8711 - Manual (Page 38)

38
PERIODIC MAINTENANCE
Inspect electrode and cable. The cable used for the connection to the
meter 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 noted, replace the electrode.
Rinse off any salt deposits with water.
For refillable electrodes:
For refillable electrodes: For refillable electrodes: For refillable electrodes: For refillable electrodes:
Refill the electrode with fresh electrolyte solution (HI 7071 for single
junction electrodes or HI 7082 for double junction). Allow the elec-
trode to stand upright for 1 hour.
Follow the above "Storage Procedure".
AmpHel ® is a registered Trademark of "Hanna Instruments"
For refillable electrodes: For refillable electrodes: For refillable electrodes: For refillable electrodes: For refillable electrodes:
If the internal electrolyte solution is more than 1 cm (½") below the
filling hole, add HI 7082 solution (3.5M KCl) for double junction
electrodes or HI 7071 (3.5M KCl+AgCl) for single junction electrodes.
For a faster response unscrew the filling hole screw during measurements.
For AmpHel
For AmpHel For AmpHel For AmpHel For AmpHel ® ® ® ® ® electrodes: electrodes: electrodes: electrodes: electrodes:
If the electrode does not respond to pH changes, the battery is run
down and the electrode should be replaced.
MEASUREMENT
Rinse the electrode tip with distilled water.
Immerse the electrode tip (4 cm) in the sample and stir gently for
approximately 30 seconds.
For a faster response and to avoid cross contaminations, before taking
measurements, rinse the electrode tip with some solution to be tested.
STORAGE
To minimize clogging and assure a quick response time, the electrode
glass bulb and junction should be kept moist at any time.
Store the electrode with a few drops of HI 70300 storage solution in
the protective cap (in its absence, use HI 7071 electrolyte for single
junction, or HI 7082 for double junction electrodes).
Follow the above "Preparation Procedure" before taking measurements.
Note: NEVER STORE THE ELECTRODE IN DISTILLED WATER OR DRY.