ABB REF 54 Series - Page 51

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Technical Reference Manual, General
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The resistance sensors may be connected to the RTD/analogue input according to
either the three-wire or the two-wire connection principle. With the three-wire
measuring principle, the wire resistance is automatically compensated. The resistor,
or RTD sensor, is connected across the IN+ and IN- inputs, and the - side of the
resistor/RTD sensor is connected to the GND input. The leads connected to the IN+
and GND inputs must be of the same type.
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With the two-wire connection principe, the IN- and GND terminals are linked
together. The resistor is connected across the IN+ and IN- inputs.
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SHUNT
IN -
GND
IN +
G
mA
DIFF
+
-
resist3w.CNV
Resistor sensor
SHUNT
IN -
GND
IN +
G
mA
DIFF
+
-
resist2w.CNV
Resistor sensor