![background image](http://html.mh-extra.com/html/national-instruments/isolated-analog-input-device-ni-pxi-4224/isolated-analog-input-device-ni-pxi-4224_user-manual_709605016.webp)
Chapter 2
Connecting Signals
2-4
ni.com
In the electrical diagrams, two different ground symbols are used. These
symbols indicate that you cannot assume that the indicated grounds are at
the same potential. Refer to Appendix A,
, for maximum
working voltage specifications.
You can make signal connections to the NI PXI-4224 through either an
NI terminal block, such as the TB-2725, or you can build a connector using
a 25-pin D-SUB.
Caution
If you are building a 25-pin D-SUB connector for your application, make sure
you use a connector and signal wires that are safety rated for the voltage and category of
the signals in your application.
Figures 2-2 through 2-5 illustrate connecting signals using a D-SUB
connector.
Figure 2-2.
Unshielded Floating Signal Source Connection Using a D-SUB Connector
+
–
Twi
s
ted-P
a
ir
Wiring
AI 0 +
AI 0 –
CH 0
V
S
IG
S
ign
a
l
S
ource
AI 7 +
AI 7 –
CH 7