9032X
45
o
Prepare two plastic beakers, one containing about 50ml of etching solution, the
other about 200ml high purity water.
o
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.
o
Dispose of the etching solution by diluting to waste with plenty of water. Use
fresh etching solution each time.
Return the electrode to the flowcell. Prior to performing a calibration, run the monitor
for one to two hours on low level sodium sample. No further calibration should be
needed until the next regen procedure.
This procedure must be carried out at regular monthly intervals and the process started
as soon as a new electrode is put into service.
Note
. It is extremely difficult to recover an ‘old’ electrode.
As the buffer solution, is replaced monthly, the following procedure should be carried
out 24 hours after replenishment to allow pH stability to be achieved.
This procedure applies to both ammonia and amine buffered systems.
5.6
SHUT-DOWN PROCEDURE -
(Prolonged Shut-Down, 1+ months)
o
Close the sample valve upstream of the monitor.
o
Remove the buffer container and safely dispose of the solution. Rinse the
containers thoroughly.
WARNING!
For safe handling instructions of buffer solutions refer to
Section 5.1.
o
Fill the CAL1 calibration solution container with high purity water and do a single
point calibration to flush the system.
o
Remove the electrodes and follow procedure in Section 5.6.1.
o
Use a syringe to flush all tubing with high purity water. This removes any
particulate deposits.
