USB-6218 (BNC) wiring differential connections

[JP brisbane]

I need to connect a differential analog input to a USB-6218 (BNC) DAQ device.  For differential measurements, AI 0 and AI 8 are the positive and negative inputs of differential analog input channel 0.  The device has a BNC connectors for AI0-7 and AI16-23.   When I configure differential inputs, is the BNC shield of AI0 actually AI08 on the USB box or will I have to wire an AI08 to one of the PFI's? 

Thanks,

[Dennis_Knutson]

Yes, the shield is ai-. Read the manual.