NI sbRIO-961x/9612XT/963x/9632XT/964x/9642XT
28
ni.com
Referenced Single-Ended (RSE) Measurements
You can use an RSE measurement configuration to take measurements on
32 channels when all channels share a common ground. Figure 19 shows
how to make an RSE analog input connection for a floating signal. National
Instruments does
not
recommend making an RSE connection for a
ground-referenced signal.
Figure 19.
RSE Analog Input Connection
In an RSE connection configuration, the NI sbRIO device measures each
input channel with respect to AI GND.
Non-Referenced, Single-Ended (NRSE) Measurements
You can use an NRSE measurement configuration to take measurements on
all 32 channels while reducing noise more effectively than with an RSE
connection configuration. This configuration provides remote sense for the
negative (–) input of the programmable gain instrumentation amplifier
(PGIA) that is shared by all channels configured for NRSE mode. The
behavior of this configuration is similar to the behavior of RSE
connections, but it provides improved noise rejection. Figure 20 shows
how to make an NRSE analog input connection for a floating signal and for
a ground-referenced signal.
Figure 20.
NRSE Analog Input Connection
+
–
+
–
AI
AI GND
Floating
S
ignal
S
ource
Ground-loop potential (V
A
– V
B
) is added
to measured signal.
NOT RECOMMENDED
+
–
+
–
AI
AI GND
V
B
V
A
Grounded
S
ignal
S
ource
+
–
+
–
AI
AI
S
EN
S
E
AI GND
Floating
S
ignal
S
ource
+
–
+
–
AI
AI
S
EN
S
E
AI GND
Grounded
S
ignal
S
ource
R
b
R
b
= 100 k
Ω
–1 M
Ω
