PCIe/PXIe-6301 Series |
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4-wire RTD connection
1
In a 4-wire configuration, the Ex+ terminal will output a current excitation, 1000 µA
and flows back through the Ex- terminal and AI- terminal as shown in Figure 5. Since
the current loop and voltage measuring circuit of the lead wire are independently, so
will not introduce errors due to lead wire resistance.
Figure 5 4-wire RTD connection
1
If you need to use a 4-wire configuration, you must configure the channel topology to
a “4
-
wire mode”
when
configuring the acquisition task. In this case, the PCIe/PXIe-6301 provides a 20 channels of temperature
measurements. If you do not need to use a 4-wire configuration, you can configure the acquisition task to a
“3
-
wire mode”
, in which case the PCIe/PXIe-6301 provides a 32 channels of temperature measurements.
