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5.4.2 pH Calibration
pH is calibrated using an external testing device or Buffer solutions.
1. Shut off the water inlet and outlet from the flow cell.
2. Remove the pH sensor and temperature probe from the flow cell.
3. Wipe the sensor probe with a dry cloth and submerge it and the (PT-100)
temperature sensor into a cup with a buffer 7 solution. Wait for the reading to
stabilize.
4. Press m
enu until “pH 7 Calibrated to” (#10) appears in the LCD display.
5. Press OK.
6. Enter the password. Press the up arrow or down arrow until the password is
reached.
7. Press OK.
8. Press OK again.
9. Press the up arrow or down arrow until the value is the same as the value
printed on the buffer 7 solution.
10. Press OK to save the new calibration or Esc to abort without saving.
11. Press
menu until “pH 4,10 Calibrated to” (#11) appears in the LCD display.
12. Press OK.
13. Enter the password. Press the up arrow or down arrow until the password is
reached.
14. Press OK.
15. Press OK again.
16. Press the up arrow or down arrow until the value is the same as the value
printed on the buffer 4 or 10 solution.
17. Press OK to save the new calibration or Esc to abort without saving.
18. Press Esc to return to the main display.
NOTE:
When calibrating pH using buffer solutions, the reading of the pH electrode will not
stabilize if the temperature probe is not also in the buffer solution.
