Chapter4 ConnectingSignals
©NationalInstruments Corporation 4-15 NI6013/6014 User Manual
Single-Ended Connections for Floating SignalSources
Figure 4-6 shows how to connect a floating signal source to a channel
configured for NRSE mode on the NI 6013/6014.
Figure4-6. Single-EndedInput Connections for Nonreferenced or Floating Signals
Single-Ended Connections for Grounded SignalSources
To measurea groun ded signal source with a single-ended configuration,
you must configure the NI 6013/6014 in NRSE input mode. The signal
is then connected to the positive input of the PGIA,and the signal local
ground reference isco nnectedt o the negative input of the PGIA.
The ground point of the signal should, therefore, be connected to the
AISENSEp in. Any potential difference between the device ground and
the signal ground appears as a common-mode signal at both the positive
and negative inputsof the PG IA, and this difference is rejected by the
amplifier. If AISENSE is connected to AIGND in this situation, the
differencein ground potentials appears as an error in the measured vo ltage.
SelectedChannel in NRSE Configuration
PGIA
InputMultiplexers
–
+
–
Floating
Signal
Source
Vs
I/OConnector
AIGND
AISENSE
ACH
+
Instrumentation
Amplifier
Measured
Voltage
Vm
–
+