Delta OHM DO 9709, Инструкция по эксплуатации

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INSTRUCTIONS FOR MAINTENANCE AND CALIBRATION OF THE DIS-
SOLVED OXYGEN PROBE
As has already been said, with the use the probe for measuring dissolved Oxygen is bound to run
down, in fact the chemical reaction which generates the current proportional to the partial pressure
of the oxygen in the water leads to the exhaustion of the electrolyte in the probe. After this the cur-
rent generated by the probe becomes so low that calibration is impossible. It is therefore necessary
to replace the electrolyte in the probe to restore its functioning.
Incautious use of the probe may also lead to damage of the oxygen-permeable membrane which
contains the electrolytic solution. In this case the membrane and the electrolytic solution that it con-
tains must both be changed.
The probe DO 9079SS allows maintenance.
Some types of probe (such as the DO 9079SH) have no maintenance. When the electrolytic solu-
tion runs out the probe must be replaced completely.
Replacement of the electrolytic solution and/or of the membrane.
1. Unscrew the head of the probe and the oxygen-permeable
membrane.
2. If necessary, replace the membrane.
3. Fill the head of the probe with the electrolytic solution up to the
level indicated on the figure (filling level).
4. eliminate any air bubbles present in the electrolytic solution.
5. Screw the head carefully back onto the probe.
ENGLISH
133
Measuring head
Pt Kathode
Ag Anode
Electrode body
Glass body
Membrane
Electrolyte solution
(Na
3
PO
4
sol)
Filling level