NI 9475 Vsup connections

[linu95k]

As per the NI 9475 manual, 

"Each channel of the NI 9475 has a DO pin to which you can connect a device. Each channel also has a COM pin and a Vsup pin. NI recommends you provide independent COM and Vsup wiring for each channel to minimize current flow in the COM and Vsup wiring. The COM pins are all connected together internally."

Therefore, can I connect different Vsup to different Channels? If yes, which Vsup pin is mapped to which DO Channel?

Which would imply for example, DO1 is sourcing 12V then can DO2 source 24V?

Or are the Vsup pins internally shorted?

I am under the impression that we can provide only Single External Supply to Vsup of the Module, i.e. the same external supply is connected to all the modules?

[rolfk]

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@linu95k wrote:

I am under the impression that we can provide only Single External Supply to Vsup of the Module, i.e. the same external supply is connected to all the modules?

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Yes they are. There is no galvanic isolation between the individual channels. What is meant with the earlier note is that if you have high currents per channel and wire the COM and VSUP all on the remote side together with one wire to the module, you can end up with large voltage drops across the wires to the module that can make the available voltage over the load significantly lower than the actual VSUP voltage.