I am using a SCXI-1127 module in independent mode to do a 4-wire resistance measurement (using a PXI-4070 DMM). I am expecting about 3 Ohms. When I first power on the station and make the measurement, the resistance is upward of 15 Ohms. I can hook up an external DMM to the 4070 leads and watch the resistance slowly decrease to the expected 3 Ohms. This is only happening with one channel in the 1127. I had a similar problem with another 1127 (I am running 8 of the 1127 modules), so I switched it out with one that is not used for resistance measurements and the problem went away. I can't switch this one out since the rest are used for resistance. So, my question is, is this a sign that the module is starting to fail? The module is about 8 years old. We had another test stand that had the same behavior. We replaced the suspect module with a new one and the problem went away. Anyone have experence in this or know if the module is failing?
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