Measuring resistance, changing excitation current

Hi, I am using a cDAQ-9172 and some 9219 modules to measure several resistances. The problem I have is that the resistances aren't entirely electrically isolated from each other, and I suspect the excitation current from measuring one resistance affects the value I record on another. For this reason I would like to sequentially switch off the excitation current on all but the channel which I'm measuring. (e.g. excite channel 1, record resistance, switch off excitation, excite channel 2, record resistance, switch off excitation and so on). Frankly I'm a little baffled on where to start with this. Until now I've been using the DAQ Assistant to set everything up, but I don't think I can achieve what I want with this, so I'm going to have to delve more deeply into communicating with the DAQ. Has anyone got any suggestions on where to start and where I can find some guides on changing the programming of the DAQ sub vi's?
Cheers

I'm getting somewhere with this, configuring one channel to read resistance and all the others to read voltage does work, but I can't get it to change which one is set to resistance. I modified the DAQ Assistant Express VI to accept channel inputs, and then I've set up for loops to generate channel numbers (of the form cDAQ1Modxaiy). The modified DAQ Assistant accepts these numbers and carries out the measurement, but then for subsequent iterations of the for loop, instead of accepting the new channel numbers it just carries out the same measurements on the same channels. Is there some way to force the DAQ to reset the channel allocations between iterations of the loop? I've attached VIs of the scanner VI and the modified DAQ assistant.
Cheers
Attachments:
Self sensing experimental-scanner2.vi ‏28 KB
TimsDAQ.vi ‏81 KB

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Measuring resistance, changing excitation current

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