Hanna Instruments HI 23 Series Instruction Manual page 34

• When the reading is stable, "CAL" will stop
• Press CFM to confirm the calibration point;
A 2-point calibration is always suggested. However the EC/
TDS calibration can also be performed at 1 point. To cali-
brate offset only, just press CAL after confirmation (with CFM)
of the zero reading; the meter will return to normal opera-
tional mode. To have the cell constant calibrated first, press
the up or down arrow keys after entering the calibration pro-
cedure to skip to the next possible calibration buffer. In this
case, after confirmation of the cell constant, the meter will
ask for the offset calibration displaying zero on the LCD; press
CAL to exit or calibrate the offset, if desired.
Note
The EC or TDS calibration value shown is referenced at 25°C
even if the reference temperature of 20°C has been selected.
Note
During calibration, press LCD to display the cell constant
value on the primary display. Press LCD again to return to
calibration buffer visualization.
Note
To interrupt the calibration procedure press CAL to exit to
normal operational mode.
Note
If the process meter has never been calibrated or an EE-
PROM reset has occurred, the meter continues to perform
measurements. However, the user is informed of an EC or
TDS calibration requirement by a blinking "CAL" indication
(see "Startup" section).
Note
The device must be calibrated within the temperature range
specified for the EC or TDS calibration solution.
34
flashing (after about 30 seconds) and
"CFM" indicator will blink.
if the reading is close to the selected solu-
tion, the meter stores the reading.
If the reading is not close to the selected
solution, "ERROR" will blink.