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New TWC buzzing and slowing charge

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Hi, I just completed my first month of Tesla ownership (Model S LR) and had a Tesla Wall Charger installed in my garage. It is about 100' from my panel, on a 60amp circuit and travels through a mix of PVC and metal conduit. I am having two issues:

1 - When charging at 48amps, the metal conduit buzzes to the point where I can hear it upstairs in the bedroom. If I lower the amperage into the 20s, the buzzing goes away. The electrician came to look at it, checked the connections to make sure they were tight, and grounded the metal conduit. He believes that the wire may be arcing, and will be coming back to take the wire out of the conduit to try and identify where the wire is damaged. While you can feel the conduit buzzing, its about the same temp as room temp (i.e. its not hot) .

2 - Most nights, I've been charging a small amount (10%), but yesterday I drove a few hundred miles so it was a pretty decent charge last night. I noticed after the first 90 minutes of charging, it had slowed down to 23 amps. I raised it back up to 48, and it remained there until the charge was complete a few hours later. Teslafi shows that the volts went from 235 to 242 when the amps came down, and when I moved it back up to 48, the voltage returned to 238. Not sure if it related, but its an interesting data point. I was assuming this was just a fluke, and didn't check to see if the conduit was hot or if the wall charger was indicating any errors.

Questions:
- Is there a log or some sort of telemetry that the charger has?
- Anyone have an buzzing/humming from their conduit/charger? Any fixes? Is it normal?

Thanks
 
If the car is changing the charge rate by itself, this indicates a voltage problem. Maybe something else in the house is turning on. You should probably stop using it until your electrician returns.
I found the cause for the slowing charge. The car was defaulting to 23 every time a charge started, and when I was in the midst of the charge, there was a blip in our electricity which caused it to default to 23. The 23 was tied to my geo location (home), and despite changing it on the app, it wasn't sticking. I had to go to the car, up it to 48 and start a charge to save the new default.
 
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