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Chapter 2
Connecting Signals
©
National Instruments Corporation
2-11
Figure 2-9.
Shielded Grounded Signal Source Connection Using a Terminal Block
Floating Signal Source Connection
Figures 2-2, 2-4, 2-6, and 2-8 illustrate floating signal source connections.
In this configuration, the signal source being measured is a floating signal
source, such as a battery. A floating signal source is not connected in
any way to the building ground system.
To connect a floating signal source connection to the NI PXI-4224, the
signal (
V
SIG
+) is connected to the NI PXI-4224 channel (AI
X
+). The
signal reference (
V
SIG
–) is connected to the channel reference (AI
X
–).
Twi
s
ted-P
a
ir
Wiring
AI 0 +
AI 0 –
CH 0
Termin
a
l Block
AI 7 +
AI 7 –
CH 7
S
hielding
+
–
V
S
IG
V
S
IG
Ground
Reference
S
ign
a
l
S
ource