Using Non-Referenced Single-Ended (Nrse) Connections For Ground-Referenced Signal Sources - National Instruments X Series User Manual

Chapter 4 Analog Input
Using Non-Referenced Single-Ended (NRSE) Connections for
Ground-Referenced Signal Sources
Figure 4-11 shows how to connect ground-reference signal sources in NRSE mode.
Ground-Referenced Signal Sources (NRSE Configuration)
I/O Connector
Ground-
Referenced
Signal
Source
Common-
Mode
Noise
and Ground
Potential
Note (NI USB-6341/6343/6346/6361/6363 BNC Devices)
ground-referenced signal source on X Series USB BNC devices, move the switch
under the BNC connector to the GS position.
AI <0..31> and AI SENSE must both remain within ±11 V of AI GND.
To measure a single-ended, ground-referenced signal source, you must use the NRSE
ground-reference setting. Use Table 4-4 to determine how to correctly connect your AI signal.
AI <0..15>
AI <16..79>
AI <80..143>
AI <144..207>
AI SENSE is internally connected to the negative input of the NI-PGIA. Therefore, the ground
point of the signal connects to the negative input of the NI-PGIA.
4-20 | ni.com
Figure 4-11. Single-Ended Connections for
+
V
s
–
+
AI GND
V
cm
–
MIO X Series Device Configured in NRSE Mode
Table 4-4. AI Signal Connections
Signal
AI <0..x>
Input Multiplexers
AI SENSE
Instrumentation
Amplifier
+
PGIA +
Measured
– V
m
Voltage
–
To measure a
Ground-Reference
AI SENSE
AI SENSE 2
AI SENSE 3
AI SENSE 4