I have 28 groups of temperature sensors made up of a mix of 2N2222 transistors and PT100 resistive thermometers. Each sensor is set up through a 2-wire lead to one of eight AD7124-8 boards and placed within a vacuum enclosure. I'm running into a periodic issue where after about 0.5-3 hours of runtime, most of the sensors will jump/drop dramatically, as shown in the attached image. The PT100 sensor temperature readings drop dramatically while the 2N2222 readings jump slightly. This all occurs simultaneously during the same reading interval. As far as I can tell, the sensor readings remain at the new reading unless a new run is initiated. The answer to why this error is happening is probably obvious, but I'm having trouble isolating it. My first thought was that the sensors were short-circuiting, but I don't know how to explain most of the sensors short-circuiting at the same time and why it would be occurring so regularly. Any insight into what might be going on would be useful. If more information is needed, I'll gladly provide it.