if signal source is floating, how can i connect my analog input signal

[ppl]

Hello,
My signal source is floating, and i use SC-2345 for signal conditioning. On the box of SC-2345, it said "Always set E series board to NRSE mode when using the SC-2345 and SCC's". My DAQ board is PCI-6036E. So, does this mean i only can configure DAQ board as NRSE mode with Measurement and Automation Explorer?
Right now, i connected the accelerometer sensor output to the SCC-ICP01 module pin 1 and 2. It says 'pin 1 and 2 form a DIFF analog input channel for measuring the voltage across the ICP accelerometer'. Is my analog input signal connection correct? The user guide of SCC-ICP01 says 'for floating signal source in high-noise environments, connect the negative terminal of the signal so
urce to the AIGND terminal on the SC-2345 screw-terminal block to reduce the common-mode noise'. But i found AISENSE ,rather than AIGND terminal there. Are they same? If not, where can i find it?
Thanks a lot!

[Filipe A.]

Hello;

The reason why you need to configure the DAQ board to be NRSE is due to a physical connection in between the SC-2345 and the AISENSE of the DAQ board, when the SC-2345 is connected to the DAQ device.
So, you definitely need to have the DAQ board configured as NRSE in MAX.

The connections you made are correct. Regarding your last question, you can connect the ch- of the SC-2345 to the AISENSE pin you found. Make sure to connect both together via a BIAS resistor. A 100k resistor should do the job.

Hope this helps.
Filipe A.
Applications Engineer
National Instruments

[ppl]

I still have one more question on this. The SCC-ICP01 module i am using in SC-2345 has such funtionality "The SCC-ICP01 input cirsuitry includes high-impedance bias resistors typically required for floating sources. External bias resistors connected to ground are not required." So, i don't need to connect any bias resistor to the ch+ and AISENSE, am i right? Thanks for your further help.

[raul1]

I HAVE ANOTHER QUESTION OF THE SAME SUBJECT:


I AM USING A 6062 DAQ. THE SC-2345 AND EIGTH SCC-A10 ATENUATOR.

IF MY DAQ IS IN NRSE, NOW I HAVE SIXTEEN DIFFERENTIALS CHANNELS?

ANY ANSWER WILL BE HELP

RAUL FEBRES
rfebres@edelca.com.ve