palintest Green Drop Kit Instructions Manual page 29

If the selected buffer value is not
within  1.0 pH from the
measured pH value: the
electrode and buffer icon blink
and the ERR annunciator
appears in the lower left corner
of the display.
4.2.3 To Calibrate conductivity:-
Ensure you wash the probe in deionised water and
store it dry and calibrate the conductivity probe at
least once a month.
If you take measurements at extreme temperatures,
calibrate the meter at least once a week.
Calibrating for Conductivity:-
1 If necessary, press the MODE key to select
conductivity mode.
Err Message and Electrode Icon
will appear if Incorrect Buffer
are Used