How can I acquire data in a PCI DAQ board using a SCXI rack?

[pablomendana]

Hello.
I have an acquisition system that consists in:
· 3 PCI DAQ boards:
- PCI-MIO-16-E-1
- PCI-6052-E
- PCI-6034-E
· 3 cables to connect PCI boards and SCXI modules
· 1 SCXI chassis:
- SCXI-1001
· SCXI modules + terminal blocks:
- 4x SCXI_1121 + SCXI_1320 (for voltage analog inputs)
- 1x SCXI_1520 + SCXI_1314 (for strain gauges)
- 1x SCXI_1530 (for accelerometers)
I have been trying to acquire different signals (specially voltage signals that are easier to reproduce) but I haven't been able to do it. I can't read anything from MAX or LabView. I have tested the PCI boards with a SCB68 terminal block (without any SCXI component) and they work properly. Problems appear when I use the SCXI chassis and the SCXI modules. I don't know if there is a problem with the hardware or it is a wrong configuration.
I guess channels in the SCXI modules correspond to analog input channels in the PCI board they are connected to, but I don't know if I have to read data from analog input channels of the PCI boards or from SCXI channels that appear in MAX (I have tried both posibilities, but they don't seem to work).
I don't know if I have to use Differential, RSE or NRSE configuration. I have tried all of them. Sometimes I only read noise, sometimes signal is fixed in a limit value (maximum or minimum, it depends), sometimes it's fixed in a value near zero,... I have changed connections and configuration options so many times I can't exactly say when one thing or another happens.
I have tested only one PCI board with only a SCXI module in order to avoid interaction and confusion. Nothing.
I think I have tried changing almost every option in MAX, but it doesn't work.
I'm sure I'm missing something and solution is quite simple, but I can't find it.
Can anybody explain to me how to connect and configure my system to read any signal? I only need a few steps or highlights. Maybe some clues about what the problem can be.
Thanks!

[AVR]

I have several comments and suggestions:

A) Have you "added a device" in MAX and actually added the SCXI chassis? This step is necessary to get the chassis to work. Click on "add a device" and choose the 1001 chassis . Do this for one DAQ card and one module only initially. The Set Up wizard should walk you through the configuration. If you are unable to add a chassis within MAX, I suspect the chassis is not working correctly.

B) Once configured, you can examine the SCXI channels in MAX as follows:
1) Open the DAQ card in MAX and Open the Test Panels
2) For the SCXI channel to view, use the following convention OB0!sc(n)!md(m)!ch where the letter (n) corresponds to the chassis number in MAX (usually = 1), the letter (m) corresponds to the module number (slot) where the module is located in the chassis, and (ch) represents the channel(or channels) you wish to view. So presuming chassis ID=1, and a module in slot 1, and you wish to view channel 3, you would type the following in the channel field for the DAQ card channel to view:

OB0!sc1!md1!3 (note OB0!sc1!md1!3:6 will display channels 3 through 6)

All of the SCXI channels for a given DAQ card are multiplexed through channel 0 of the DAQ card, Channels 1 and up are not used, hence the initial three characters in the SCXI call refer to "On-Board Channel 0 (OB0)"

C) For the subsequent set up, it will be necessary to first add the additional modules to the chassis (when powered off). Then open MAX and update the chassis. (If you get an error then simply delete the chassis reference in MAX and add a new chassis). You will then be required to set the interface mode of each module as either parallel or multiplexed. In parallel mode, you associate a distinct module with a distinct DAQ card in the host PC. For those DAQ cards that will address multiple modules, you must first configure the modules to be in adjacent slots in the chassis and then assign the first module to the cabled DAQ card - then all of the modules assigned to that DAQ card should be configured in "multiplexed" mode.

D) Once the chassis has been properly configured, you can click on each module and set the gains, filters, and terminal block types.



I hope that this helps to get you started.

[pablomendana]

Thank you very much.
I had done almost all the things you have mentioned in your message and it didn't work, but I discovered there was a broken fuse in the SCXI rack. I replaced it and now it works perfectly.
Thanks!