alpha-pH 1000
11
6 CALIBRATION
MODE
You can reach the Calibration mode directly from the Measurement mode by pressing the CAL key and
entering the Calibration security code. You can also reach the Calibration mode from the Advanced
Setup mode.
6.1
pH Calibration
This unit features 7 preset buffer values (1.01, 4.01, 6.86, 7.00, 9.00, 9.18 and 10.01)
for fast auto calibration. When you calibrate this instrument, you need a standard pH
buffer solution that matches one of these values.
1)
Enter Calibration mode. While in the Measurement
mode, push the CAL key and scroll to Calibration code
“11”. Push the ENTER key again. The upper and lower
display reads “CAL pH”.
NOTE: If the display read “CAL OrP”, see section 7.6.2 for
procedures on how to switch from ORP to pH readings.
2)
Press the ENTER key again to begin calibration. The
“CAL” indicator appears at the top of display and the buffer
indicator appears in the bottom left corner of the display.
The upper display shows your present uncalibrated
reading. The lower display indicates one of the two buffer
values used for the first point calibration. It would either be
7.00 or 6.86.
3)
Press the
!
or
"
key to scroll the lower display to
the buffer value that matches your buffer solution.
4)
Make sure the electrode is in the buffer solution. In
ATC, you must also immerse the temperature probe in the
buffer solution. Likewise for symmetrical mode, you must
also immerse the potential matching pin in the buffer.
5)
Press the ENTER key to confirm the buffer value and
start the calibration of its first point. The electrode indicator
and CAL indicator both flash. The controller automatically
adjusts the reading to match the buffer value.
6)
The lower display will now show its next lower ‘pH’
buffer. Use
!
and
"
keys to select its second buffer from
one of the 5 preset values. Remove the electrode from the
first buffer, wash and then immerse into the second buffer,
Once the upper display stabilises press the ENTER key,
the electrode and CAL indicator will flash. The controller
adjusts the reading to the buffer.
7)
After calibrating to a second buffer value, this controller will automatically display slope in the upper
display and zero point in the lower display. You can view the values for zero point and slope without
calibration --- see section 5.1.2 for instruction The zero point and slope are re-determined after
each calibration.
8)
Press the ENTER key. If you entered the calibration mode using the CAL key, the controller will
return to the Measurement mode. If you entered the calibration mode from the Advanced Set-up
mode, the controller will return to the sub-function menu.
CAL
PH
SETUP
HOLD
HOLD
59.0
mV
7.00
pH
6.96
pH
7.00
pH
CAL
4.02
pH
4.00
pH
SETUP
HOLD
CAL
READY
HOLD
CAL
