Supercharger's Transformer, almost too hot to touch with just me charging, Opinions?

[islandbayy]

Just curious for those of you in the Industry (A certain PowerCo Exec comes to mind....)
I was at the Madison Supercharger Friday night at about Midnight to 1 am. Ambient temps were cool, mid 60's, breezy, and foggy. We were the ONLY car charging, and were gently sipping the juice at about 40kW (Was towing a trailer for the first time, so wanted to top off to make sure I had enough power).

The Supercharger got it's own DEDICATED 500kVa transformer. The transformer feeds 3 supercharger cabinets with 3 stalls (Was originally approved for 6 stalls for the 3 cabinets, but the mall owners did not want 6, and only allowed 3).

So while waiting, the kids were sleeping in the car, so I went for a lil stroll to stretch the legs. Went by the transformer, and it was just radiating heat. Wasn't buzzing too loudly. So I felt one of the heat sync fins. It was Freakin Hot!!! Longest I could FORCE my hand on it was about 30 seconds. Opinions if that is normal?
Once again, this is on the Utility's Transformer, NOT any of Tesla's equipment. And again, it is Dedicated to the Superchargers only. 500kVa feeding a maximum draw of 360kW (The Superchargers are still the 120kW variety).

Does that sound about right? For it to be painful, and I have mild sense loss in my arms and hands, about 25% loss due to a accident a number of years ago, but for it to be painful I believe temps must exceed 130*F.

Cheers!

 

[yobigd20]

Touching a heat sink... Not the brightest of ideas. Then again, maybe you are a criminal and you want to singe off your fingerprints before you go kill somebody. lol

You ever touch the heat sink on your computer or graphics card? Those can easily hit temps above 220f under load. And that's just for a CPU or gpu using just a fraction of 120V 15A.

 

[RandyS]

Something doesn't sound right with that description. A 500 kVA transformer only feeding the normal SC load of 3 units plus 40 kW of charging load should not be getting that hot. Either the transformer is powering other heavy customer load, or there is something wrong with the transformer...It would be interesting to take an infrared temperature read of similar conditions plus another read or two when more cars are charging...Something doesn't add up...

 

[islandbayy]

Touching a heat sink... Not the brightest of ideas. Then again, maybe you are a criminal and you want to singe off your fingerprints before you go kill somebody. lol

You ever touch the heat sink on your computer or graphics card? Those can easily hit temps above 220f under load. And that's just for a CPU or gpu using just a fraction of 120V 15A.

For a pad mounted transformer in the middle of a busy parking lot, should not be getting to those temps, at least not without some sort of barrier protecting it. Im going to upload a picture I took of the transformer. Obviously no cars around it, but at Midnight, we were one of 5 cars in the entire lot. Buffalo Wild Wings was still open...

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Something doesn't sound right with that description. A 500 kVA transformer only feeding the normal SC load of 3 units plus 40 kW of charging load should not be getting that hot. Either the transformer is powering other heavy customer load, or there is something wrong with the transformer...It would be interesting to take an infrared temperature read of similar conditions plus another read or two when more cars are charging...Something doesn't add up...

Agreed. Just getting opinions here before I contacted MG&E, which I fired off a email to them anyways. The Transformer is new, and was previously non-existent before the Supercharger. I usually have my IR Thermometer with me, however, it was in my other tool box that night. I am going to bring it next weekend. See what it's temp is. If it was day, I wouldn't be surprised of the heat, with the sun beating down on it all day, but at midnight-1am, should have cooled a bit.

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transformer pic

 

[yobigd20]

could it just be the sun baking it all day? i mean honestly on some days you can't even sit on a metal chair outside bc it was just sitting in the sun all day and it'll burn your ass in 30 seconds.

 

[FlasherZ]

Perhaps it was a combination of the transformer's cooling fluid (oil) holding heat from the day plus your charging.