Questions about SCXI products

[Natan_T]

I would like to ask about a few SCXI boards.

1) The datasheet of the SCXI-1102 mentions a maximum sampling rate of 333 ksam/sec.  However, no further details regarding sampling are given anywhere in the datasheet.  I am confused.  Does this board sample or not?  If not, can I use any DAQ board to sample it?

2) The same question regarding SCXI--1126

3) The SCXI-1140 is called a "simultaneous sampling analog input."  However, its datasheet does not mention sampling rates or resolution anywhere.  What does this board do?

[tnek]

Hi Natan,

All SCXI modules except for the SCXI-1600 do not sample since none of them have an analog to digital converter. Many of them have a multiplexing circuitry inside which allows the channels to be multiplexed together. The scan rates which are listed in the specifications for the modules which you inquired about pertain to the multiplexer. The modules which are housed in a SCXI chassis must then be connected to a DAQ card or a SCXI-1600 for control and analog to digital conversion. More information on how SCXI functions can be found in the Getting Started with SCXI manual.

The SCXI-1140 utilizes simultaneous sample and hold (SS/H) signal conditioning. This makes the effective delay between channels very small which allows the user to correlate data between channels. More detailed information about this circuitry can be found in the SCXI-1140 User Manual.

Regards,
Kent
Applications Engineer

[Natan_T]

First of all, thanks for your prompt response.  I would like to pursue this a little further.

1) Regarding the SCXI-1102 - the datasheet says 333 ksam/sec maximum sampling rate, but does not mention simultaneous sampling.  Does this mean I cannot sample simultaneously from this board?

2) Let's say I have a chassis with one SCXI-1102 (thermocouples) sampling 12 channels and one SCXI-1520 (strain gauges) sampling 8 channels.  I need to simultaneously sample the strain gauges at 100 ksam/sec, and simulatenously sample the themocouples at 100 sam/sec.  If I understand your response correctly, I would need to add a DAQ board to the chassis that would do the actual sampling?  What board could handle those sampling rates?

3) Do you have A-to-D board with over 16 input analog channels?

[tnek]

Hi Natan,

Here is a resource which may answer many of your questions on SCXI. Many of the products can be found through the links here so you can find hardware which matches your needs. Again, I would refer to the Getting Started with SCXI guide which gives great introductory information about SCXI. The SCXI-1102 module is not simultaneous sampling. However, depending on how fast your temperature is changing, this may not be too important.

Regards,
Kent
Applications Engineer