National Instruments 24-Bit Half/Full-Bridge Analog Input Module NI 9237 Operating Instructions Manual page 8

The NI 9237 has a four-terminal external excitation voltage source
connector. You can use the EX+ and EX– terminals on the
connector to connect one external excitation voltage source to the
module. You can use the additional EX+ and EX– terminals on the
connector to wire multiple NI 9237 modules together in a daisy
chain.
Note
NI 9237, slight changes in the excitation voltages can
cause a mismatch between the internal half-bridge
completion resistors and the half-bridge sensors, which
results in a change in the measurement offsets.
National Instruments recommends performing bridge
calibrations of quarter- or half-bridge sensors after
connecting all sensors to the NI 9237 and after removing
or attaching any additional sensor. Visit
and enter the info code
about changes in voltage offsets in the NI 9237.
NI 9237 Operating Instructions and Specifications
When you insert or remove a new sensor from the
for more information
rdw9237
8
ni.com/info
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