I have been successfully using the AD595 to measure the temperature of a thermocouple I have and have confirmed that I can measure the temperature correctly using a myRIO (DAQ card). It measures about 0.300 volts when I am at room temperature which is about 30 degrees Celsius. However, when I turn on other components in my system the analog signal from the AD595 spikes rapidly and begins to oscillate between 1 and 4 volts.
I have wires running directly next to my thermocouple wires that have 24V DC and 5V DC running through them a low amps. The length of interface between these wires is about 2 feet. I was wondering how important having shielded thermocouple wires is and if this could be the problem I am experiencing. I have ran a few tests using different input pins on my DAQ card and confirmed that the problem is not within the DAQ itself. Could you please point me towards some possible issues that could be causing the thermocouple reading to oscillate like this?