Hanna Instruments HI 9910 - Manual (Page 23)

23
SET
READ
8.00
COARSE FINE SLOPE OFFSET
SET POINT
pH
6.00
COARSE FINE SLOPE OFFSET
SET POINT
pH
6.18
ACID
ALK
Make sure that the electrode (and any ground probe) is properly
installed and calibrated (see the preceding pages).
FOR HI 9910
Turn the switch to the "SET" position (see 7 - Functional Diagram).
The display will show the previously adjusted value (e.g. pH 8.00).
Using a small screwdriver, first adjust the setpoint through the
COARSE trimmer and then fine tune it to your required level with the
FINE trimmer (see 3 and 4 - Functional Diagram) until the desired
set value is displayed (e.g. pH 6.00).
DOSING DIRECTION
Select the direction of dosing through the "ACID"/”ALK” switch (see 8
- Functional Diagram). In order to dose acidic substances (i.e. lower
the pH value) leave the selector on "ACID". When dosing base or
alkaline solutions (to increase the pH) select the “ALK” position.
e.g. Dosing acidic liquids
Setpoint = pH 6.00
Measured value = pH 7.00
To reach the setpoint you need to dose acid, therefore
move the switch to the "ACID" position (see 8 - Functional
Diagram).
ADJUSTEMENT OF SETPOINT(S) ADJUSTEMENT OF SETPOINT(S) ADJUSTEMENT OF SETPOINT(S) ADJUSTEMENT OF SETPOINT(S) ADJUSTEMENT OF SETPOINT(S)