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FOR HI9911 (DUAL-POINT ADJUSTMENT)
a) ACID SETPOINT and DOSAGE
To set the upper limit and direct the controller to lower the pH value,
set the SET/READ switch to “SET” and the ALK/ACID switch to “ACID”;
the display shows the higher setpoint (e.g. pH7.00).
Using a small screwdriver, adjust the two “ACID SET” trimmers. First
adjust the “COARSE” trimmer and then tune through the “FINE” trimmer
until the desired setpoint value is displayed (e.g. pH8.00).
b) ALKALINE SETPOINT and DOSAGE
To set the lower limit and direct the controller to increase the pH value,
set the SET/READ switch to “SET” and the ALK/ACID switch to “ALK”;
the display shows the lower setpoint (e.g. pH6.00).
Using a small screwdriver, adjust the two “ALKALINE SET” trimmers.
First adjust the “COARSE” trimmer and then tune through the “FINE”
trimmer until the desired setpoint value is displayed (e.g. pH5.00).
