15
6. Press
ENTER
to con
fi
rm that the ppm value is the desired
standard. The displayed value will show the corresponding
mV reading for the selected ppm value. Allow the reading to
stabilize.
7. When the mV reading is stable, press
ENTER
to complete the
calibration for the second standard. The display will show the
next highest calibration standard value. Rinse the electrode with
clean water.
8. To calibrate a 3rd point, repeat steps 6 & 7. To exit from 2-point
calibration, press the
CAL
key.
9. The ISE slope in mV value “
PXX mV
” will momentarily be
displayed before reverting to the ion measurement mode.
If the calibration is not successfully stored in the memory, an error
message “
Er3
” will be displayed. This occurs when the slope is lower
than 15mV/decade or higher than 90mV/decade.
3.3 Temperature Calibration
3.3.1 With Temperature Probe
The temperature probe supplied with the meter is factory calibrated. Over
time, the temperature calibration may drift and require recalibration. If
the temperature probe is replaced the meter should be recalibrated.
1. Connect the temperature probe to the meter. Press the
MODE
key until the “
°C
” annunciator appears on the DISPLAY.
2. Compare the displayed value to a NIST certi
fi
ed thermometer or
other thermometer known to be accurate. For the most accurate
results, place both the probe and thermometer in a constant
temperature bath.
