1MS/s/ch Simulltaneously sampled, Single Ended Analogue Voltage measuremnt DAQ

[sm81]

Hello there, I have been looking up your products for something I need for my work. I have been looking for simultaneously sampled (1MS/s/ch) analogue channels for 'Single Ended' measurements. I can't find any DAQ (USB/PXI/PXie) which can do this. I have PXie-6124(4MS/s/ch, 0 SE, 4 DI), which according to one of your colleagues, can't do SE because it doesn't support RSE/NRSE. I am currently using PXI-6251 (1.25MS/s, non simultaneously sampled) which is fine as long as I use 2 or less channels (I can divide the sampling rate by 2 and still good) and  I can do both SE and DI. But, I can't find a DAQ which is both simultaneously sampled and allows SE. Any reason why I can't/ shouldn't do this?  Thanks.

[Izzzzz]

Hello sm81, 

You could still configure a single ended measurement with a device that is typically meant fo differential inputs. Connect your single ended signal to the + terminal and the ground of your system to the - terminal of the device. Although, please ensure you still stay in the Common Mode Range of the device. 

Best Regards,

Izzy O.

Applications Engineer

National Instruments

www.ni.com/support

[sm81]

Hi Izzy O.,

That sounds plausible but I am trying to understand how would you access the + and - on the device? PXIe-6124 has a high density 68-pin interface and I am using

 BNC2120 to access the individual analogue channels. On my MAX, I can see AI0-AI3. Could you suggest how do I find AI0-, AI0+ etc? Do I need a differnt connector block?

Currently my signal outputs are BNC connectors.

[Izzzzz]

Hello sm81, 

If your signal outputs are BNC connectors then they are most likely a differential twisted pair and not single ended. I would connect the signal output BNC to the AI channel on the BNC 2120 you wish read the signal on.  

Best Regards,

Izzy O.

Applications Engineer

National Instruments

www.ni.com/support