WIKA A-10 to DAQ 9203

[Sharkboy3221]

Hello,

I'm attempting to take pressure measurements using 4 WIKA A-10 pressure transducers. I'm using an 9203 DAQ card. I have a Tek Power HY3006D DC power source supplying the required 8 volts to the transducers. I'm confused because I've followed multiple wiring diagrams that all lead me back to where I started. 

I found this through one of the NI forums and followed it:

Not sure what the dotted lines going from the voltage source to the sensors mean. I assumed that those are negative wires. I'm not sure why those are there though. I'd think that you'd only want the COM port wire going back to the negative port on the voltage source.

My set up looks like this now:

The only things not shown in the picture is the output wires coming from the pressure transducers to the ports on the DAQ cards. The ground wires are coming from the pressure transducers. The box on the left is my power source.