NI SCXI-1127, Руководство пользователя

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Chapter 2 U s i n g the SCXI-1127
6A ± Excitation for Four-Wire Channel 6
6B ± Sense for Four-Wire Channel 6
Sense Output 1
Excitation Input —
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XI-1331
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SCXI-1127
Figure 2-7. Four-Wire Wiring Diagram
On power up the ABO and AB2 switches are open, disconnecting the
SCXI-1127 from the high-voltage bus. If you are using this module with a
high-voltage backplane, you need to close the ABO and AB2 switches to
connect the EXCITATION and SENSE commons to the HVAB backplane.
Figure 2-7 shows an example of a four-wire configuration using the
SCXI-1331 terminal block. The diagram shows the four-wire terminal
block connections for channels 1 and 12. Resistance is measured on both
channels. Each channel has excitation pair + and - terminals labeled I A and
I 2A and SENSE terminals labeled 1B and 12B respectively.
RI is excited through the 12A + and - screw terminals and the voltage drop
across the resistor is measured through the 12B + and - screw terminals.
SCXI-1127 User Manual 2-8 © National Instruments Corporation