National Instruments NI 9421

NI 9421/9423 10 ni.com
Connect the output of the sourcing-output device to DI on the
NI 9421/9423. Connect the common of the external device to the
COM terminal or pin. Refer to Figure 3 for an illustration of
connecting a device to the NI 9421/9423.
Figure 3. Connecting a Device to the NI 9421/9423 (3-Wire Device Shown)
NI 9421/9423
+
–
Sourcing-Output
Device
COM
DI
External
Power
Supply