Verify my maximum achievable sample rate .

[skilagig]

I am using a PXI 6031E and an SCXI 1001 Chassis populated with six 1102c modules. I am setup to multiplex 192 channels to one DAQ channel(0). I am using every channel on every module. The 1102c is cable of 333KS/sec but using all 32 channels my max should be a little more than 10Khz. My PXI 6031E is capable of 100KS/sec but now I am limited by the module speed so the best I can get is around 10Khz. Is this correct?

[Filipe A.]

Hello;

The maximum multiplexer rate of the SCXI chassis is 333KS/s, therefore the macimum sample rate per channel will be given by:

Maximum Sample rate per channel = 333K/n; where n is the total number of SCXI channels on your system, regardless the speed of the DAQ board connected to the system.

On your case, since you have 192 channels, the maximum per channel rate will be 333K/192 = 1734S/s.

Regards
Filipe A.
Applications Engineer
National Instruments

[skilagig]

Thanks Filipe,
I guess this would be a good explanation of why my scan function keeps timing out (because I have the sample rate too high).
George T.

[Andband]

I have a problem that's kinda similar.

We are using a PXI 6031E in a PXI 1036 housing connected to a computer with a PXI 8360 MXI card.

I was trying to measure 17 Channels at 10k, but it just didn't work. According to the Datasheet, the max. sample rate of the 6031E is 100kHz.

Then I figured, that maybe the whole sum of all used channels may be 100kHz.

The maximum samplerate that works is 7262 Hz.

But 7262 * 17 is about 123 000, which is more then 100 000. 

Could someone could explain, whats behind that?