Chapter 3
Configuring Your SCXI Hardware and Software
©
National Instruments Corporation
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RSE Input (Eight Channels, Factory Setting)
RSE input means that all input signals are referenced to a common ground
point that is also tied to the SCXI-1200 analog input ground. The
instrumentation amplifier negative input is tied to analog ground. The RSE
configuration is useful for measuring floating signal sources. With this
input configuration, the SCXI-1200 can monitor eight different analog
input channels.
Considerations for using the RSE configuration are discussed in the
SCXI-1200 User Manual. Notice that in this mode the return path of the
signal is analog ground at the connector through the AISENSE/AIGND
pin.
NRSE Input (Eight Channels)
NRSE input means that all input signals are referenced to the same
common-mode voltage, which floats with respect to the SCXI-1200 analog
ground. This common-mode voltage is subsequently subtracted by the
input instrumentation amplifier. The NRSE configuration is useful for
measuring ground-referenced signal sources.
Considerations for using the NRSE configuration are discussed in the
SCXI-1200 User Manual. Notice that in this mode, the return path of the
signal is through the negative terminal of the amplifier at the connector
through the AISENSE/AIGND pin.
Note
To measure the conditioned signals provided by analog input modules in the same
chassis, the SCXI-1200 must be configured for NRSE input mode.
DIFF Input (Four Channels)
DIFF input means that each input signal has its own reference, and the
difference between each signal and its reference is measured. The signal
and its reference are each assigned an input channel. With this input
configuration, the SCXI-1200 can monitor four differential analog input
signals.
Considerations for using the DIFF configuration are discussed in the
SCXI-1200 User Manual. Notice that the signal return path is through
the negative terminal of the amplifier and through channel 1, 3, 5, or 7,
depending on which channel pair you select.