Can I perform FFT analyses using fieldpoint inputs ?

[Nickams]

I need to perform an FFT analyses for an acceleration signal supplied by a 100mv/g constant current accel. The plant concerned are using Field point, FP VB10 units with lab windows. FFT needs to be no more than 0-1000 Hz band width. Need to integrate signal to velocity and band pass data. FSD for velocity - 30mm/sec rms, 10G acceleration. Also need constant current driver for a sensor. Can this be achieved with field point system. As I suspect not, can you advise a suitable NI product that can achieve the task at reasonable cost.

[Aaron_G]

FieldPoint is not currently suitable for FFT analysis at high speeds as it does not provide deterministic sampling mechanisms. By this, I mean that each I/O module will sample all of it's inputs at a fixed rate that is independant of the controller. Thus a controller may read the I/O module multiple times during a sample period if the sample period is slow (FP-TC-120 has a 1.13 second sample period for all channels), or may miss one or more conversions if the sample period is fast (FP-AI-100 has a 2.8 ms update rate).

Better products for doing FFT analysis are the MIO E-Series DAQ boards. An MIO E-Series DAQ board does not have the ability to create a constant current source (it optionally has voltage outputs but not current outputs), but SCXI does have curren
t output modules such as the SCXI-1124. For more information on these modules, I recommend posting in the DAQ forums.

Regards,
Aaron