Hi Gary,
Thankyou for posting to the National Instruments Discussion Forums.
This Knowledge Base explains what different power options are available for the SC-2345 carrier box.
With the power option you have you can use +5V from either your DAQ board or an external power supply. The external power supply connects at the molex connector and generally a DC apater.
As such, if you're specific application is running correctly using power from the DAQ board and you do not need extra current, you should be fine with the current setup.
Hope this helps!
Abhinav T.
Applications Engineering
National Instruments India
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