NI 9234 Minimum Sampling Rate

[LR2a]

Hi,

I am relatively new to LabVIEW/cRIO, and am in the process of undertaking a vibration shaker test, using a 3 degree of freedom sensor that uses a CAN bus protocol, utilising  a NI 9853 CAN bus module to measure the force output.  A second force sensor is connected to the shaker, to measure the input force in a single direction.  This second sensor is connected to an NI 9234 module.  I am then looking to log the data from both simultaneously and save to a .CSV file.

I have the two systems working independently of one another and logging data, but I am just in the process of trying to integrate them on a single VI.  The 3 degree of freedom sensor is configured as standard to sample at 1 kHz and this cannot be changed.  From the NI 9234 datasheet, the lowest sampling rate quoted is 1.652 kS/s or 1.652 kHz. 

I was wondering if there is any way that this can be configured to read at 1 kHz.  One option I did read was to use a loop timer, but I’m not sure if this would work.

For the testing I need to sample each sensor at the same sampling rate so that the same time stamp can be assigned to both readings.  This will make post processing the results easier.

I have read through the literature, but I am not sure if achieving a sampling rate of 1 kHz is possible.  This is my first attempt at using an NI 9234 module and I am not 100% sure of its capability at the moment.

Any advice would be much appreciated.

Kind regards

[JÞB]

Supply an external timebase of 256kHz * n where n=1-31

[LR2a]

Hi Jeff.p.Bohrer,

Many thanks for your reply, and the suggestion of using an external timebase of 256 kHz.  Would you be able to give me an idea of how to do this on the FPGA VI?  

The only thing I can find is using a loop timer set to 1 mS which I believe to be wrong.  All references I can find on the internet outline the use of an internal clock but not an external one.

Any help would be appreciated 

[mcduff]

The 9234 is a delta-sigma module, the only external clock it can use has to be from another delta-sigma module. So you would need another c series module that has the proper rate. Then you could use that clock.

mcduff