GE AKTA avant User Manual page 82

3 Standard instrument modules
3.9 pH valve and pH monitor
Flow path
Restrictor
and pH
pH
Calibration
pH monitor
The pH monitor continuously measures the pH of the buffer and eluted proteins when
the pH electrode is in-line. When pH monitoring is used, the pH monitor should be cali-
brated every day.
The pH monitor can be calibrated with the pH electrode installed in the pH valve. For
instruction on how to calibrate the pH monitor, please refer to Section 7.7.2 Calibrate the
pressure monitors, on page 323.
The following illustration shows the location of the pH flow cell and a pH electrode in-
stalled in the pH valve.
82
Description
Both pH electrode and Flow restrictor are in use.
pH electrode is in use and Flow restrictor is by-passed.
Flow path used when calibrating the pH monitor and when filling the
pH flow cell with storage solution. The Cal port is used to inject solution
into the flow cell using a syringe.
Excess solution leaves the valve through port W3.
Part Function
1 pH flow cell
2 pH electrode
ÄKTA avant User Manual 29035184 AE