Instruction manual - Mettler-Toledo

Zero
Zero point calibration
Zero point calibration
The Series InPro6000 sensors have a very low zero current.
Therefore, a zero point calibration is only recommended for
measurement of oxygen traces. If a zero point calibration is
performed, the DO sensor should remain for at least 10 to 30
minutes in the calibration medium in order to obtain stable,
non-drifting values.
During zero point calibration, a drift check is not performed.
Zero point current of a properly functioning sensor is notably
less than 0.5 % of air current. The display (secondary: measured
value, main: entered value) does not change until an
input current is entered for the zero point.
When measuring in an oxygen-free medium, the displayed current
can be taken directly.
Display Action Remark
Activate calibration
(press cal key)
Enter mode code 1001
Select with key, edit number
with key, proceed with enter
Place sensor in oxygen-free
medium
Main display:
Zero point current;
store with enter
or correct with arrow keys and
then store with enter.
Lower display:
Sensor current measured
The Transmitter is in
the Hold mode;
If an invalid code
is entered, the
Transmitter returns
to measuring mode.
Display of slope
Display of new zero point current
End calibration with enter
key, place sensor in process
New calibration:
Press cal key.
The oxygen value is shown in
the main display alternately
with “Hold”; “enter” flashes.
Stop Hold with enter.
After end of calibration,
the outputs
remain in Hold
mode for approx.
20 sec.
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