WIKA Pascal ET Betriebsanleitung Seite 31

6. Commissioning, operation
The calibrator is now set for measuring an RtdUser by using the 4-wire (4W) "IN A" input and displaying the temperature in °C.
The button indicated with
10
indicated that if the button will be pressed for long time, a different function can be selected. By pressing and keep pressed
that button you can enter the pages for setting the desired parameters related to the custom or user thermoresistance (Ptd).
The following screen appears:
Measurements of RTD - 4-wire
If possible it is recommended to perform RTD measurements with 4-wire to eliminate parasite resistances of the
connection cables. All specifications for resistance thermometer aim for 4-wire measurement.
RTD USER must be selected when the operator needs to measure a non-standard RTD in agreement with the following
formula:
If T≥ 0 °C R(t) = Ro * (1 + A * t + B * T²)
If T< 0 °C R(t) = Ro * (1 + A * t + B * T² + C (t – 100) * t³)
Where:
-3
A = X * 10 °C-1
-7
B = X * 10 °C-2
-12
C = X * 10 °C-3
Ro = Resistance @ t = 0.01 °C
X = Value
Further specific parameters can be also configured for the already configured channel by pressing the button
WIKA operating instructions, model Pascal ET
in the previous picture now shows a little with triangle in the right-down corner: this symbol
Fig. 21 - Setting parameters for RtdUser
EN
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