19
18
16. "CALC" is displayed on the upper LCD for
a few seconds and the meter is cali-
brated and ready to use.
17. If the buffer is wrong or the electrode is
defective, "Err" will be displayed to alert
the user. When calibration is completed,
the instrument checks the electrode pa-
rameters and advises the user of abnormalities by "old probe"
and "dead probe" indications (in these cases, repeat the calibra-
tion with fresh buffers).
CALIBRATION ERROR MESSAGES
If the "old probe", "dead probe" or "Err" messages are displayed
during calibration, check your electrode by following the conditioning
and maintenance procedure and repeat calibration. The pH electrode
might have to be replaced if calibration cannot be successfully
performed.
CALIBRATION DATA PRINTOUT
It is possible to print the characteristics of the electrode as a recording
of the electrode performance over time by setup code 12 (see "Printing
GLP data").
This will consist of: date, time, the offset characteristic of the pH
electrode in mV, the slope characteristic in mV/pH and the pH buffer
solution values.
If calibration has been performed with an "old" pH electrode the first
line is:
pH **
If calibration has been performed with a "dead" pH electrode the first
line is:
pH --
If the calibration alarm time-out is expired, the "
Dt
" string will be
printed beside the date.
Note:
A dashed line indicates that the calibration has never been
performed.
6. If password is correct or not set, the
meter will display "7.01pH" on the up-
per LCD and "b1" on its lower part; if
wrong, it will return to measurement
mode without any message.
7. Select the first buffer solution value with and if necessary.
8. When the "S" symbol blinks in the lower
LCD, the reading is stable and calibra-
tion can be confirmed.
Note
:
It is possible to display temperature pressing the RANGE key.
9. Press ALT and CFM to confirm the first buffer.
10. If everything is satisfactory the LCD will
display CALC and then the second buffer
value expected will be displayed. If a
wrong solution or electrode has been used or if the buffer is
polluted, "WRONG" will be displayed to alert the user.
11. If only a single point calibration is re-
quired, press ALT and CAL to leave the
calibration mode and maintain the previ-
ous slope calibration. "CALC" will be displayed
for a few seconds. The instrument then
checks the electrode parameters and ad-
vises user of abnormalities by "old probe"
and "dead probe" indications.
12. Press or to select the second
buffer value. The "b2" symbol will be
fixed on lower display.
13. Rinse the electrode with some of the second
buffer solution or clean water.
14. Dip the bottom, 4 cm (1½"), of the electrode
in a beaker containing the second buffer.
15. When the "S" symbol blinks in the lower
LCD, press ALT and CFM to confirm the
second calibration point.