Ground-Referenced Signal; Figure 2-1. Connecting A Ground-Referenced Signal - National Instruments Module SCXI-1125 User Manual

Chapter 2 Connecting Signals

Ground-Referenced Signal

SCXI-1125 User Manual
completely isolated from other channels. You can operate with
common-mode voltage levels up to 300 V
Figures 2-1 through 2-4 show signal connection methods that give the
highest noise immunity.
When the negative input signal line is connected either directly or
indirectly to earth ground (usually at the transducer end), connect this line
to the negative input terminal, as shown in Figure 2-1. No ground
connection is made at the SCXI-1125. This situation includes cases where
a floating source can be riding on a high common-mode voltage that is
ground referenced.
+
V
s
–
+
V
cm
–

Figure 2-1. Connecting a Ground-Referenced Signal

rms
+
High
I
CMV
Module
2-2
.
+
V
out
–
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