But I didn't have time to react before the second tech confronted me and asked what the problem was. "Let me show you a picture," I said. I pulled out my iPhone with the IR scan of the connector showing a temperature of 112.8˚ C. I knew by the stern look on his face that he recognized the problem. He agreed that we needed to change the cable at the first available opportunity.
We waited until lunch, when rehearsals would be over, and once we changed the cable, the temperature dropped down to about 35˚C and everything was fine.
Although the connector is rated 105˚ C, the lug inside of the power distro is likely rated at only 90˚ C. I've never seen one rated higher than that. So even though the first temperature measurement was below the 105˚ C rating of the cam-lock connector, I would have opted to swap out the cable even if the temperature had not risen. Luckily, I didn't have to work very hard to convince the crew to swap it. Disaster averted.
By the way, the tool I used to scan the distro was a Flir One, which is an attachment for the iPhone (also available for Android). It cost $400 for the Pro version, and it's well worth it. You can buy a laser pointed thermometer, but it would have been much more challenging to find the problem quickly with that instrument. There were five feeder transformers and 10 or 12 distros. Scanning all of the cam-lock connectors with a laser beam would have taken a very long time. The IR camera picks up the entire distro in one view, and you can see the relative temperature of all five cam-lock connectors at a glance. If one looks hotter than the other, then you can zoom in and read the temperature of an individual connector, which is how I found this problem.