SCXI 1126 frequency channels are unstable when two or more are connected.

[mtdtest]

I have two proximity sensors picking up the spoke of a pully wired into my SCXI-1126 module.  The signal jumps around a lot while both are working.  When only one is sensing and the other is not the signal works good without any problems.  It seems like I am getting cross talk between the two channels.  This is not the first time I've used an 1126 module.  I've done it in other applications with similar sensors without problems.  Could it be the type of prox switch I'm using?  I've got two omron npn sensors.  Is there something else that I am overlooking. 

[Justin_M]

Hi mtdtest,

Can you check which revision of the 1126 you have?  It will be a letter in the part number, which will look something like:

pn: xxxxxxA-xx

where the x's are numbers.  The above would be a rev A board.  Let us know what revision your board is.

Thanks,

Justin M.

National Instruments

[mtdtest]

The part number is: 184345D-01 Rev:2.0

mtdtest

[Justin_M]

Thanks mtdtest.  Revision D is a slightly older version of the board, and this may be related to the issue you are seeing.  You'll need to contact technical support to continue troubleshooting this issue.  You can create a service request online by going to the Request Support page and entering in your information.  Once you create your request, can you please post your service request number here so I can follow the issue as well?  Thanks!

Justin M.

National Instruments