ATI
Q45P pH System
Part 5
–Calibration
35
O&M Manual
Rev-B (7/15)
2. If the sensor has been removed and placed into a buffer, allow sensor to
temperature equilibrate with the buffer as much as possible. With the sensor
coming from an application which differs greatly in temperature difference, the
user may have to wait as much as 20 minutes. If the sensor is on-line, the
user may want to set the output HOLD feature prior to calibration to lock out
any output fluctuations.
3. Scroll to the CAL menu section using the MENU key and press ENTER or the
UP arrow key.
Cal pH
will then be displayed.
4.
Press the ENTER key. The screen will display a flashing 1 for 1-point or a 2
for 2-point calibration. Using the UP arrow key, set for a 1-point calibration
and press ENTER.
5. The system now begins acquiring data for the calibration value. As data is
gathered, the units for pH and temperature may flash. Flashing units indicate
that this parameter is unstable. The calibration data point acquisition will stop
only when the data remains stable for a pre-determined amount of time. This
can be overridden by pressing ENTER. If the data remains unstable for 10
minutes, the calibration will fail and the message
Cal
Unstable
will be
displayed.
6. The screen will display the last measured pH value [or the auto buffer value, if
activated] and a message will be displayed prompting the user for the lab
value. The user must then modify the screen value with the arrow keys and
press ENTER. The system then performs the proper checks.
7. If accepted, the screen will display the message
PASS
with the new offset
reading, and then it will return to the main measurement display. If the
calibration fails, a message indicating the cause of the failure will be
displayed and the FAIL icon will be turned on.
