Single-Ended Connections For Floating Signal Sources (Rse Configuration); Single-Ended Connections For Grounded Signal Sources (Nrse Configuration) - National Instruments AT E Series User Manual

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Floating
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Signal
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Source
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I/O Connector
© National Instruments Corporation
Single-Ended Connections for Floating Signal
Sources (RSE Configuration)
Figure 4-8 shows how to connect a floating signal source to an AT E Series
device channel configured for RSE mode.
ACH
Input Multiplexers
AISENSE
AIGND
Selected Channel in RSE Configuration
Figure 4-8. Single-Ended Input Connections for Nonreferenced or Floating Signals
Single-Ended Connections for Grounded Signal
Sources (NRSE Configuration)
To measure a grounded signal source with a single-ended configuration,
you must configure the AT E Series device in the NRSE input
configuration. The signal is then connected to the positive input of the
AT E Series PGIA, and the signal local ground reference is connected to
the negative input of the PGIA. The ground point of the signal should,
therefore, be connected to the AISENSE pin. Any potential difference
between the AT E Series ground and the signal ground appears as a
common-mode signal at both the positive and negative inputs of the PGIA,
and this difference is rejected by the amplifier. If the input circuitry of an
AT E Series device were referenced to ground, in this situation as in the
RSE input configuration, this difference in ground potentials would appear
as an error in the measured voltage.
Programmable Gain
Instrumentation Amplifier
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PGIA
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4-25
Chapter 4 Connecting Signals
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Measured
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m
Voltage
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AT E Series User Manual