Maintenance
44
Waltron User Manual 101-045-E.1
9031CX Sodium Analyzer
4.5
SCHEDULED SERVICING
The following procedures are guides to the maintenance requirements of the monitor. The procedure
chosen depends on the particular installation and sample conditions.
4.5.1
WEEKLY MAINTENANCE
If the monitor is continuously running at high concentrations, greater than 100ppb, a weekly Single Point
Calibration is recommended.
4.5.2
MONTHLY MAINTENANCE
Replace the bottle of reagent buffer solution. The level of solution should not be allowed to fall below
about three-quarters full. On high ambient temperature installations and for low sodium concentrations,
the solution may require replacement more frequently.
Check the level of reference electrode filling solution; refill as required.
It is recommended you calibrate at least once a month
The following procedures should be carried out:
When the sodium concentration is above 1ppb, carry out a Two Point Calibration note the slope value.
4.5.2.1
Sodium Measuring Electrode Etching/Regeneration Instructions:
When the sodium concentration is below 1ppb, apply the following regeneration/etch procedure before
carrying out a Two Point Calibration:
ATTENTION
When used for prolonged periods at low concentrations, leeching of sodium
ions from the electrode surface accelerates the aging process of the
electrode which is shown by poor response time, low slope value and a
limitation to respond to low levels. Calibration may then be in error because
of slow response and poor reproducibility. The reactivation procedure
minimizes problems from these sources.
Also: Etching is not for new probes, it is part of the monthly maintenance
procedure.
Remove the sodium electrode from the flowcell and slide off the sleeve and ‘O’ ring; it is not necessary
to detach the electrode lead.
Prepare two plastic beakers, one containing about 50ml of etching solution, the other about 200ml high
purity water.
Dip the electrode in the etching solution for 60 (
5) seconds; then rinse in high purity water.
CAUTION
It is important not to exceed the etching time or the performance of the
electrode may be permanently degraded.
Dispose of the etching solution by diluting to waste with plenty of water. Use fresh etching solution
each time.
