Single Point Calibration; Dual Point Calibration - Mettler Toledo InPro 6950 Serie Bedienungsanleitung

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– F or correct calibration, a minimum flow rate of the
calibration medium is necessary.
– M ake sure that all other parameters, such as
temperature and pressure, are constant.
For continuous applications, we recommend periodic
recalibration in line with your requirements on
accuracy, the type of process in operation and
your own experience. The frequency of the need
for re- c alibration depends very much on the specific
application, and therefore appropriate intervals can-
not be exactly defined here.

5.2.3 Single point calibration

By carrying out a single point calibration, the factual
slope of the sensor can be established. The cali-
bration medium can be water with known oxygen
saturation index (e.g. air-saturated water) or air with
known water-vapor saturation (e.g. water-vapor satu-
rated air).
After the sensor signal has stabilized, the com-
plete meas uring system can then be calibrated to
the100 % value of the desired measurable variable,
e.g.100 % air, 20.95 % O
(77 °F) and normal pressure (see instruction manual
for the transmitter).

5.2.4 Dual point calibration

By carrying out a dual point calibration both slope
and zero point of the sensor can be established.
Important! In case of a dual point calibration,
always start by the zero point calibration before
calibrating the slope.
As a rule, the zero point should be adjusted to zero
manually, or it is automatically performed by the
transmitter (see instruction manual for the transmitter).
Zero-point calibration is recommended:
– when measuring less than 5 ppb in liquids
– w hen measuring less than 125 ppm (by vol.) in
gases
Attention! Incorrect zero point calibration is a
frequent source of measurement error. For correct
calibration, we recommend the use of carbon
dioxide gas with a level of purity of at least
99.9995 %.
After the sensor signal has stabilized (after 6 ... 12
hours), the sensor can be calibrated through the
relevant transmitter to the 100 % value of the de-
sired measurable variable, e.g. 0 % air, 0.0 % O
0.0 ppm (see instruction manual for the transmitter).
InPro 6950
52 206 137 F
InPro 6950 Series O
, or 8.26 ppm at 25 °C
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© 02 / 2023 METTLER TOLEDO
Sensor 12 mm
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Printed in Switzerland
, or
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