Factory Calibration; Single Point Calibration (Slope Or Process Calibration); Process Calibration - Mettler Toledo InSUS H60i Bedienungsanleitung

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• Make sure that all other parameters, such as tempera-
ture and pressure, are constant�
• Calibration always needs accurate pressure and tem-
perature measurement. Only process scaling is indepen-
dent of those parameters (see chapter 5.2.4).
• Make sure that the correct calibration pressure, humidity
and salinity values are set in the transmitter before the
calibration is started.
• Please refer also to the transmitter or biocontroller man-
ual for detailed
5�2�2 Factory Calibration
The sensor head is delivered pre calibrated and ready for use.
The factory calibration data are stored in the
and cannot
5�2�3 Single Point Calibration (Slope or Process Calibration)
For most applications, a single point calibration should be
sufficient.
By carrying out a single point calibration, the factual phase
at the desired oxygen value e.g. at hundred percent oxygen
(phi 100) of the sensor can be established. The corre-
sponding calibration curve is calculated.
The calibration medium can be either air or a calibration
gas with a
a known oxygen concentration.
Before starting a calibration in gas, the correct pressure
and the correct humidity have to be set in the transmitter.
h Note: Wrong pressure values are the most common rea-
sons for bad measurement accuracy�
E.g. A 50
and the value set in the transmitter result in a 5 % mea-
surement error
For calibration in gas, it is important that the temperature
reading of the sensor is stable and represents the real gas
temperature.
After the sensor signal has stabilized, the complete mea-
suring system can then be calibrated to the 100 % value
of the desired measurable variable, e.g. 100 % air, 20.95 %
O , or 8.26 ppm at 25 °C (77 °F) and normal pressure (see
2
instruction manual for the transmitter).
5�2�4 Process Calibration
For detailed information please
manual.
Two different routines for process calibration are possible:

• Process calibration

• Process scaling (M400 / M800 transmitter)
Process calibration is performed when a reliable control
value is available and process pressure is known. Process
pressure is only needed if the system is measuring in sat-
uration (% air or % O
this calibration the phase values of the calibration curve
are adjusted.
Process scaling is performed mainly in biopharma appli-
cations when the user desires to set the system to an initial
value. During this calibration the phase values of the sen-
sor are not adjusted, only the displayed values and the
4 – 20 mA output are rescaled to the desired value.
h Note: For process calibration, the operator can use either
the process pressure or the calibration pressure, depending
on how the reference value is taken.
InSUS H60i
30 802 188 A
information.
be changed by the user.
known O concentration or
2
mbar difference between the ambient pressure
in air.
2
process medium
also refer
) or gas (ppm gas) units. During
© 09 / 2022 METTLER TOLEDO
InSUS H60i
sensor head
to the transmitter
Printed in Switzerland
with