09-29-2014 02:17 AM - edited 09-29-2014 02:18 AM
Hello,
the NI SCB-68A connector has several Analog Ground "A GND" and "D GND".
All Analog Grund are not connected to other Analog Ground, means when i try
to measure from one AGND to another AGND.
Does that mean that i must connect ALL AGND to my source ground or only one?
If so all AGND must connected to each other on my PCI-6225 internally. Is that the case?
Do i need to connect all digital grund or just one?
09-29-2014 11:07 AM
The PXI-6225 is tricky as the two Connectors "0" and "1" have very different ground assigments, but the SCB-68A connector block attached to either appears the same. Furthermore, the SCB-68A schematic on the inside of the cover is only for Connector "0" and only if you have cabled with the SHC68-68-EPM cable. Lastly, the SCB-68A has circuitry selectable via on-board switches. So, please describe exactly which 68-pin connector ("0" or "1") on the PXI-6225, and which cable ("EPM" or other), and the position of the switches.
09-29-2014 11:23 AM
The grounds are connected inside of the DAQ card. Therefore, you do not want the grounds connected in the terminal block.