National Instruments FieldPoint cFP-RTD-122 Operating Instructions Manual page 6

Leave this wire
4-wire RTD
Figure 5. Four-Wire RTD Connections on One Channel
Taking Measurements from Two-Wire RTDs
Connect either wire of a two-wire RTD to the EX+ terminal and the
other wire to the COM terminal, and connect a short jumper wire
between the COM and SENSE terminals.
2-wire RTD
Short Jumper Wire
Figure 6. Two-Wire RTD Connections on One Channel
Measuring Resistance Directly
You can use the [c]FP-RTD-122 to measure resistance in ohms.
In this way, you can take measurements from RTDs of types that
the [c]FP-RTD-122 does not directly support (such as 120
RTDs) and from resistive devices other than RTDs. You can choose
one of two resistance ranges: 0–400 and 0–4,000 . Resistance
values outside the range you select, including open circuits, result
in an
Out of range
[c]FP-RTD-122 ignores any configuration of RTD type for
channels with resistance ranges selected.
FP-RTD-122 and cFP-RTD-122
unconnected
error for the affected channels. The
EX+
SENSE
COM
[c]FP-RTD-122
EX+
SENSE
COM
[c]FP-RTD-122
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