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Upgrading panel and subpanel to have a Wall Connector

I have NEMA14-50 in my garage, and would like to install Wall Connector using the same line.
Currently a subpanel has a 50amps circuit breaker for this line --


This subpanel is fed from the main panel, and has 60amps circuit breaker --


Subpanel has a few other circuit breakers as you can see on the first photo, not just the charger:
- kitchen outlets (x 3)
- bath outlet
- washer
- dish washer
- garbage disposal.

So it's roughly 10amps left to all of the above (with 50 amps for the circuit breaker).

Question: what circuit breakers I should use if I upgrade NEMA14-50 to a Wall Connector?
I think it should be:
- main panel's circuit breakers 60 amps -> 70amps for the subpanel;
- subpanel's circuit breakers for the EV charger 50 amps -> 60 amps.

The main panel's main circuit breaker is 200amps, and I think it's sufficient for the combined load.

PS. Extra karma question -- are there any limitations on the length of a line that's feeding into the Wall Connector?
My previous EV was a Leaf (charging on the front), vs Tesla has charging port on the back, so I have to park backing into the garage,
to reach the back of the car, or I am thinking to put the Wall Connector on the other wall so probably need to use bigger gauge
wires to maintain some resistance, but could not find any guidance on this.

PPS. I am planning on installing the Wall Connector myself, like I did the NEMA14-50 and the line that went from the subpanel to garage.

Thanks for any info!
You don't NEED to upgrade any breakers to use the wall connector.... just set it to a 50 amp breaker/40 amp charge rate and you'll be all set.

If you want to upgrade to 60/48 amps, you first need to check if your wire from the main to the subpanel can take any more than 60 amps continuous. If so, you could upgrade the breaker on the main panel feeding the subpanel to whatever the ampacity of the wire is(or 100A, whichever is LESS, since that's the max of your subpanel). It is debatable if you can round up here, since most of the load will be continuous. I'm also not real clear if the round up rule can EVER be used feeding subpanels.

Next you need to make sure the wire you installed to feed the 14-50 is capable of 60 amps continuous. That means either 4 gauge NMB(romex), or 6 gauge individual conductors in conduit. If that is true, you can upgrade the subpanel breaker feeding your HPWC to 60 amps.

If it isn't already clear, I wouldn't bother with any of this. I'd stick with 40 amp charging unless I had a recurring need for the absolute max(48), or even stick with a 32 amp mobile charger(although I don't see a GFCI breaker there, which will increase your costs considerably if you want to get it inspected)

As far as line length limits, I believe there are none, but you can use Voltage Drop Calculator | Southwire to see what a wise length would be.

The charge cord on the HPWC is 24 feet long, so there's not a real strong reason to move it from the current location. It is a decent reason NOT to use the UMC(mobile charge cord), since it is shorter.
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Super helpful, thanks @Sophias_dad

FWIW, I was not patient with waiting for an answer so also posted my q here Upgrading panel and subpanel to have a Tesla Wall Connector charger (48amps)
Ya.. I should have pointed out out that the subpanel is probably going to be overloaded if its really delivering 40A continuous, depending on the other loads of course. It isn't really sufficient to look at the other breakers in the subpanel, you need to look at what they are driving(or likely to drive). In this case I see 4x20 amp breakers on each leg, and the highest load is likely to be a countertop oven or microwave oven. You might well be able to get 50 amps(40 amps continuous), as I look further. Keep in mind that temporary overloads are very well handled by circuit breakers. Running that microwave that takes ~10 amps over the 60 amp limit of the subpanel breaker for a minute or two is unlikely to trip the breaker.
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I had this setup for ~4 years, with my previous EV - Nissan Leaf that also had a level 2 charger, same line. Never tripped in this situation,
It's a Leaf. That explains a lot. I was concerned for a 50A circuit plus other things running from a 60A line from the main panel. But the Leaf doesn't have a 10 kW onboard charger that can pull 40A continuously. It only has I think about a 7 kW, so it can use about 30A. So that's not fully consuming that 50A circuit as I was concerned about.
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