I have the following short questions regarding the NI 9205 module, which I use in connection witht the RIO:
- Floating input, how to connect COM?
In the manual of the NI-9215, a bias resitor of about 1M (connected to AI-) was suggested to provide a defined common mode voltage if the source was floating. This resitor was even in-built in the version with the BNC housing. This makes sense, but it was not mentioned inside the NI-9205 manual; can I use the same method to connect floating inputs?
The sampling rate was mentioned to lay inbetween 200kS/s and s250kS/s. In the FPGA, module setup, I can adjust a time between conversions between 4us and 8us. I am not quite sure about the precision issue. If you sample multiple channels at <8us, probably the precision will decrease, due to the settling time. However, If I sample only a single channel, I could utilize the full 4us/250KS/s without loss of precision, right?