I am using an SCXI 1000 chassis with an 1102 module. It reads negative DC voltages ok. But it does not read posititive voltages properly above about +4V. I believe that I have isolated the problem to the chassis because I have replaced the chassis with another, keeping all other hardware (module, terminal block, cable, DAQ board) the same. With the replacement chassis, results are fine. I have also checked the fuses behind the fan, and they seem to be ok. Can anyone provide any guidance? Thanks.
Have you tried to use any other modules in this chassis? Will any of these devices work properly?
This bad SCXI 1000 chassis also had the 1163 module (digital outs) as well as the 1124 module (analog outs). Once that I determined that the chassis appeared to be having a problem with analog inputs on the 1102, I switched it out for another SCXI 1000 since I needed a running system for my operations. Do you think that testing the bad chassis with either the 1163 and/or 1124 would provide useful evidence? If so, I can try to find the time to bring it back on-line and do such testing.
It sounds like it is in fact a problem with the SCXI chassis. I would recommend giving us a call so that we can start walking through the RMA process. Please create a service request on our website at: http://sine.ni.com/apps/utf8/nicc.call_me
Let me know if I can answer any other questions for you.