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4.3 Linearity calibration
1. Proceed with basic calibration, see above.
2. Add 1 % of the temperature span to the selected "minimum"
temperature and set this value on a PT 100 simulator (when
using a precision resistance decade, where necessary ob-
serve DIN IEC 751 conversion table from °C to Ω!) and cali-
brate the signal conditioner output signal to 0.100 V using
the null potentiometer.
3. Set the mean temperature "(ϑ
max
+ ϑ
min
)/2" on the PT 100
simulator.
Determine the difference to the desired value:
"∆U = shown value on measuring instrument - 5.000 V" and
calibrate the output signal to (5.000 V - ∆U) using the span
potentiometer.
4. Set the "maximum" selected temperature ϑ
max
on a PT 100
simulator and calibrate the signal output to 10.000 V using
the lin potentiometer.
5. Repeat steps 2 to 4 until the required accuracy is achieved.
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