+24VDC is used to inner circuit to measuring channels. So yes you need two connections of power.
One for card itself and other for sensors for making voltage or mA data to channels.
It can be used from same supply (+24VDC, or separate DC or AC source ).
depending how measuremt is connected and how it takes power, there is 2, 3 or 4wire connection and talk of passive and active power conecction to PLC.
Analog output card makes usually voltage or mA of card supply.
Digital outputs are relay or transistor outputs. Relay card needs separate power, transistor outputs give voltage out directly.
Hi Lare,
If the U connectors at the back of the modules power the modules would you still be required to connect a 24VDC connection to the pins if using an external PSU to power as per the diagrams??
Thanks Callum
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