Adjustement of setpoint – Hanna Instruments HI 9931 User Manual

Page 17

• Once the controller is calibrated to a solution by referring to its

value at 25 °C, all subsequent measurements are temperature
compensated to 25 °C. You can also obtain temperature compen-
sation to a different temperature reference point by calibrating
the meter to that value. For example, the conductivity and TDS
value of HI 7031L and HI 70442L at 20 °C are 1.28 mS/cm
and 1358 ppm, respectively. By adjusting the display to these
two values, all subsequent measurements are compensated to a
base temperature of 20 °C.

Calibration is now complete.

Make sure that the probe is properly installed and calibrated (see
the preceding pages).
Turn the switch to the "SET" position (see 8 - Functional Diagram).
The display will show the previously adjusted (e.g. 1.60 mS/cm or
1400 ppm).

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 4 and 3 - Functional Diagram) until the desired
value is displayed (e.g. 2.1 mS/cm or 1700 ppm).

ADJUSTEMENT OF SETPOINT

SET

READ

1.60

FINE

COARSE

SET POINT

SLOPE

CAL

ZERO

CAL