horiba LAQUA-PC1100, Instruction Manual

Page: 97 / 117

Maintenance
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Maintenance and storage of the ORP electrode
For the detailed procedures for maintaining and storing electrodes, refer to the
instruction manual for each electrode. This section describes an overview of the
procedures for maintenance and storage to be performed as part of daily use.
• How to clean the electrode
When the tip of an electrode (responsive membrane and liquid junction) becomes dirty,
the response speed may become slow or an error may occur in the measurement
results. To avoid such error, clean the electrode. For dirt that cannot be removed by pure
water (or deionized water), use the cleaning solution indicated below depending on the
type of dirt. After cleaning, rinse the electrode with pure water (or deionized water).
• Daily storage of the electrode
If the electrode becomes dry, the response will become slow. Store in a moist
atmosphere. Follow the steps below to properly store the electrode.
1. Clean the electrode well with pure water (or deionized water) to remove sample
completely, and close the internal solution filler port.
2. Clean inside of the protective cap with pure water (or deionized water), then add
enough pure water (or deionized water) to soak the sponge.
3. Attach the protective cap.
• When the electrode will not be used for a long period
To store the electrode for a long period, follow the electrode storage procedure above,
and in addition, use a dropper or similar tool to replace the reference electrode internal
solution (model 300) with new solution. Replace the internal solution once every three to
six months.
Type of dirt Cleaning solution
General
Diluted neutral cleaning solution
Oil
Inorganic substance
Immerse dilute nitric acid (1:1 nitric acid)