Weidmuller PT 100/4 signal conditioners for current output - Manual (Page 7)

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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 r esistance decade, where necessary ob-
serve DIN IEC 751 conversion table from °C to
Ω
!) and cali-
brate the signal conditioner output signal to 0.200 mA using
the null potentiometer .
3. Set the mean temperatur e "(
ϑ
max
+
ϑ
min
)/2" on a PT 100 simu-
lator.
Determine the difference to the desired value:
"
∆
I = shown value on measuring instrument - 10.000 mA"
and calibrate the output signal to (10.000 mA -
∆
I) using the
span potentiometer .
4. Set the " maximum" selected temperatur e
ϑ
max
on a PT 100
simulator and calibrate the signal output to 20.000 mA using
the lin potentiometer .
5. Repeat steps 2 to 4 until the required accuracy is achieved.