Maintenance and care
multi EA 5100
150
¡
Due to risk of short-circuits: Prevent fluids from entering the stirring/cooling block
and the plug-in contacts.
14.11.3 Maintenance and storage of the electrodes
Combined electrode
NOTICE
Risk of possible destruction of the electrode due to cleaning, abrasive or polish-
ing agents.
The combined electrode consists of ceramic materials which is mechanically sensitive es-
pecially near the fused electrodes.
¡
Only rinse the combined electrode with ethanol and ultrapure water to clean it.
When handled incorrectly, the electrical connection of the combined electrode can
break.
¡
Carefully remove the electrode from the lid of the measuring cell.
¡
Grip the electrode from above and pull it straight out of the lid.
¡
Do not pull on or jerk the side connection sleeve for the electrical connections. The
connections in the sleeve will break otherwise (not visible from outside)!
Figure 72Correct handling of the combined electrode
Drying of electrolyte on the combined electrode can cause an irreversible reduction of its
sensitivity or damage the electrode. Therefore, make sure that the electrolyte never
dries on the combined electrode.
¡
For brief operational interruptions (one full day): Store the combined electrode in
fresh electrolyte solution.
¡
When put out of operation for multiple days: Carefully rinse the combined electrode
with ethanol and subsequently rinse it with ultrapure water. Also rinse the inner
opening for the gas inlet while doing so. Wipe the combined electrode with cellulose
and store it in dry condition.
¡
For intensive cleaning: Fill the measuring cell with ethanol. Insert the combined
electrode in the measuring cell and allow the solution to stir for several hours in the
detection module. Do not connect the measuring cell or the electrode to their elec-
trical connections for this.
¡
Before an end point routine: Store a new combined electrode or one that has been
stored in a dry place in fresh electrolyte solution for at least one hour.
