12
symmetrical mode, immerse the potential matching pin in the buffer.
4)
Press the ENTER key
to start the calibration at pH 7 (or pH 6.86). The
electrode indicator and CAL indicator both flash. The controller automatically
adjusts the reading to match the buffer value.
5) The lower display will now show its next lower ‘pH’ buffer. Use
∆∆∆∆
and
∇
∇
∇
∇
keys
to select the second buffer from one of the 5 remaining 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 k
ey, the
electrode and CAL indicator will flash. The controller adjusts the reading to
the buffer.
6) After calibrating to a second buffer value, the controller automatically
displays electrode slope and offset. The zero point and slope are re-
determined after each calibration.
7)
Press the ENTER key.
If the calibration mode was accessed
using the
CAL key
, the controller will return to the Measurement mode. If the
calibration mode was accessed from the Advanced Set-up mode, the
controller will return to the sub-function menu.
Note:
If there is a calibration error, the controller displays “ERR”. If this
happens, push both and (escape) to restart the calibration beginning from
step 1.
Note:
When calibrating with manual temperature compensation, the
controller automatically changes from the preset process temperature to the
calibration temperature. After leaving the Calibration mode, the controller
switches back to process temperature (for setting the calibration temperature
and the process temperature, see section 7.2.3).