Hach POLYMETRON 9245 Manuel D'utilisation De Base page 10

Sample pH conditioning check
Non-cationic applications
1. Install a calibrated pH sensor in the center position of the measurement chamber which is
normally used for the ISE sodium electrode (No. 1 in
2. On the analyzer, press Start on the main menu to start the measurement process.
3. Check that the pH value of the sample after conditioning is greater than 10.5. If not, check the
quality of the conditioning product used.
Cationic applications
1. With a calibrated pH sensor, measure the pH of the sample outside of the analyzer.
2. Determine the gas injection time ratio depending on the sample pH. Enter this value into the
analyzer as described in
standard values are:
• pH = 2.0 - Tgas/Twater ratio = 180%
• pH = 2.3 - Tgas/Twater ratio = 80%
• pH = 2.6 - Tgas/Twater ratio = 50%
• pH = 2.9 - Tgas/Twater ratio = 30%
• pH = 3.5 - Tgas/Twater ratio = 15%
• pH = 4.0 - Tgas/Twater ratio = 10%
3. Install the same pH sensor in the center position of the measurement chamber (No. 2 in
on page 6).
4. On the analyzer, press Start on the main menu to start the measurement process.
5. Measure the pH in the conditioned sample to check if the pump ratios are efficient enough to
obtain a pH of around 11.0. If necessary, update the ratio to maintain a final constant pH of 11.0 ±
0.2.
Reference electrode installation
1. Remove the reference sensor from its box.
2. Remove the plastic reservoir from the bottom (the storage solution is KCl 3M) and install the O-
ring as shown.
3. With care, turn the bottom electrolyte tube ferrule with a maximum ¼ turn to lock it.
4. Remove the plastic plug on the entry port.
5. Install the reference electrode in the extreme left measurement chamber (No. 2 in
on page 6).
6. Connect the reference cable (the one without the blue label on it) to the reference electrode.
7. Connect the electrolyte tube to the entry port on the reference electrode.
Sodium ion selective electrode installation
Note: It is critical to preserve the integrity of the sodium ion selective electrode as much as possible. This is why
this electrode must be installed at the very last moment after all other adjustments.
10 English
Total gas/water ratio (cationic applications only)
Figure 1 on page 6).
on page 14. The
Figure 1
Figure 1