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UMC Cable Failure

I've been charging my MS at home using the UMC for about a year now without any issues and the SvC checked the cable during the annual inspection, but a few days ago charging was interrupted and the car warned that there was a charge cable failure. I had to unplug the UMC from the wall and replug it as well as replug it into the car. All seems to be fine now, but I was wondering if this is anything to be concernd about or maybe the unseasonably hot weather may have had a role in this issue.
I had the exact same problem occur the day before yesterday. It wasn't unseasonably warm, but I wasn't worried about it either. If it happens again, I plan to ask my SvC about it. My car goes in next week anyways and they typically do a customary check of the UMC, so I would probably be set either way.
Well, I'm on my fourth UMC now. The first one had a bent retainer catch on the end that plugs into the 14-50 adapter. The second and third both started having intermittent problems....sometimes the car would click numerous times and then either fail to start charging (red ring) or it might start charging. Other times it would start charging but them immediately drop the amps from 40 to 30. Both times the local SC checked the UMC and provided a replacement.

I keep one UMC in my garage plugged in at all times. It is supported with a hook and hose reel so there is no strain on the cable. This is the one which has failed. I keep another in my car for travel purposes....it has been used only a few times but I've never had a problem with it.
One thing to check is the temperature of the UMC cable between the plug and the controller. I had my UMC replaced after that upstream portion of the cable measured at 160oF (71oC). After replacing, it now runs at 105oF (40oC). Here is a link to the data I collected showing on the bad UMC cable . . .


On the fun side of things, this little experiment revealed that I could buy a nice handheld pyrometer-type temperature measurement device (with laser pointer) for less than $20 on Amazon - a nice tool to have lying around for quick, easy surface measurements.