National Instruments PCIe-6323, User Manual

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X Series User Manual
Using the DAQ Assistant, you can configure the channels for RSE or NRSE input modes. Refer
to the
Configuring AI Ground-Reference Settings in Software section for more information about
the DAQ Assistant.
Using Referenced Single-Ended (RSE) Connections for Floating
Signal Sources
Figure 4-9 shows how to connect a floating signal source to the MIO X Series device configured
for RSE mode.
Figure 4-9.
RSE Connections for Floating Signal Sources
Note (NI USB-6341/6343/6361/6363 BNC Devices) To measure a floating signal
source on X Series USB BNC devices, move the switch under the BNC connector to
the FS position.
Using the DAQ Assistant, you can configure the channels for RSE or NRSE input modes. Refer
to the
Configuring AI Ground-Reference Settings in Software section for more information about
the DAQ Assistant.
Connecting Ground-Referenced Signal Sources
What Are Ground-Referenced Signal Sources?
A ground-referenced signal source is a signal source connected to the building system ground.
It is already connected to a common ground point with respect to the device, assuming that the
computer is plugged into the same power system as the source. Non-isolated outputs of
instruments and devices that plug into the building power system fall into this category.
The difference in ground potential between two instruments connected to the same building
power system is typically between 1 and 100 mV, but the difference can be much higher if power
distribution circuits are improperly connected. If a grounded signal source is incorrectly
measured, this difference can appear as measurement error. Follow the connection instructions
S elected Ch a nnel in R S E Config u r a tion
PGIA
Inp u t M u ltiplexer s
–
+
–
Flo a ting
S ign a l
S o u rce
V
s
I/O Connector
AI GND
AI S EN S E
AI <0.. 3 1>
+
Progr a mm ab le G a in
In s tr u ment a tion
Amplifier
Me asu red
Volt a ge
Vm
–
+