Multichannel simultaneous acquistion

[czur]

Hi all

Am using PXI 6280 DAQ card to acquire temperature data, is it possible using PXI 6280 to sample all 16 analog input channels simultaneously?. how do i do it?

the DAQ card is placed on the SCXI 1052 chassis with 8 SCXI 1125 signal conditioning modules, and 8 1328 terminal boxes.

is it possible that i acquire data from 2 signalcondioning modules at once, at the same point?

and how would i know that my DAQ is in multichannel simltaneous sampling mode or acquiring data 1 channel ata time.

Thanx and regards

Arun

[Norbert_B]

Arun,

it is not possible to sample multiple channels via a M-Series card simultanously. This is caused by the architecture of the card. It uses a multiplexer inside to route all inputs to a single ADC (analog to digital converter). The main advantage of this architecture is that you only need a single ADC for each card, reducing the cost of production VERY significantly. On the other hand, you can therefore sample only "quasiparallel" and the maximum samplerate of the ADC (e.g. 250 MS/s) is divided down evenly by the number of channels you sample. The offset between the channel is set to a value the ADC & multiplexer need to switch from one channel to the next. If this offset is too large for your application, you should consider using a S-Series card which has a single ADC for each channel, resulting in simlutanuous sampling, but less channels per card and higher costs.

If your SCXI-modules are configured as multiplexed, you can of course synchronize several modules if they are all connected to the same DAQ-card. There are plenty of examples available for using DAQmx with SCXI.

Norbert B.

PS: please consider to ask questions like this one, which is definetly a hardware question, into the apropriate forum (multifunction DAQ in this case)

Message Edited by Norbert B on 05-18-2006 08:58 AM