LABEC M-TIT-5 - Manual (Page 44)

Set burette or set burette coefficient is simple, user just need to select ‘10ml burette’ or ’20ml
burette. After selecting burette, select burette coefficient, user only needs to key-in the burette
coefficient marked on burette. When setting finished, press ‘Enter’ to return to starting status.
11. Electrode Calibration
Before pH titration begins, electrode slope can be calibrated. If users needs to make two-point
calibration, two kinds of standard buffer solutions must be prepared beforehand, if user needs to
make one-point calibration, then one kind of standard buffer solution is enough. Preparation of
standard buffer solution is shown in Appendix.
11.1 One-Point Calibration
One point calibration means the electrode system is calibrated with only one kind of pH
standard buffer solution to calibrate automatically the Eo of the meter. The meter will take
percentage slope of pH combination electrode as 100%. This method can be used to simplify
the operation if precise measurement is not required. The procedure of operation is as follows:
a. Insert pH combination electrode and temperature electrode into measuring electrode sockets,
clean the electrode with distilled water and put it in pH standard solution B (any one of the three
pH standard buffer solutions).
b. In starting status, press ‘Calibrate’ button, displayed as follows:
Diag. 58 Calibration in menu
View Titrate Mode Set Calibrate
Press ‘Enter’ button, meter will enter into one-point calibration working status. At this time, meter
displays the current measured pH value and temperature. Displayed as Diag.59:
Diag. 59 One –point Calibration in starting status
Calibrate
Calibrate electrode slope
Titrate
Enter
Clean
Exit
Feed
Titration Panel READY + K 10/21
View Titrate Mode Set Calibrate
Calibration/one-point calibration
Titrate
7.00
pH
Clean
Titration Panel READY + K 10/21
25.0
℃
Enter Exit
Feed
43