Weidmuller PT 100/4 signal conditioners for current output - Manual (Page 11)

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4.5 Linearity calibration
1.
Carry out a basic calibration, see above.
2. Set the selected " minimum" temperatur e on a PT 100 simula-
tor (when using a pr ecision r esistance decade, wher e neces-
sary observe DIN IEC 751 conversion table from °C to
Ω
!)
and calibrate the signal conditioner output signal to 4.000 mA
using the null potentiometer .
3. Set the mean temperature "(
ϑ
max
+
ϑ
min
)/2" on a PT 100 simu-
lator.
Determine the difference to the desired value:
"
∆
I = shown value on measuring instrument - 12.000 mA"
and calibrate the output signal to (12.000 mA -
∆
I) using a
span potentiometer .
4. Set the " maximum" selected temperatur e
ϑ
min
on the 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.