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HPWC prep question

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I’m having Tesla install a 6kw solar system (no powerwall), just awaiting the permitting.

I’ve got an electrician coming out next week to preinstall a sub panel in my garage to wire up two 220 outlets in my garage on 100amp breakers for future car charging.

Should I have them drop them on 14-50 outlets or leave the lines capped and shut off? Is there a difference in charging ability if the HPWC is plugged in or tapped direct?
 
I just removed a 14-50 and replaced it with a HPWC. An electrician friend and I did it in just a few minutes. It's pretty easy:

  1. Turn off power.
  2. Verify you turned off power.
  3. Carefully start taking things apart assuming you didn't turn off the power (should probably check at this point).
  4. Figure out the placement of the HWPC.
  5. Drill holes for the bolts.
  6. Dry fit.
  7. Move it to the correct location because although we checked several times and marked it, we were off by about 2cm.
  8. Bolt it on. Hook up the three necessary wires.
  9. Give it power and do a quick test.
i.e., if you have the HWPC, just hardwire it. If you don't have it, do a 14-50 and use that until you get tired of using the mobile charger. Then get the HWPC and hard wire it.
 
What kind of charge rate can you expect to see on 100amps?

on a 100A breaker, the wall connector can charge at a maximum of 80A. thats about ~54 mi/hr on a model S.

However, all new Model S/X only have a max of 72A charging if you bought a 100D. Only the older pre-facelift Model S have the "dual charger" setup which can charge at 80A. So if you wanna put it on a 90A breaker for 72A max charging, that's acceptable too.

Now the only reason it would make sense to put it on a 100A breaker is if you had two teslas, and two wall connectors that load balance, then you can potentially charge 2 cars at 40A each.
 
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One will be for a car. The other is for an upgraded air compressor with the ability to convert to a second car charger later

If you've got two different things on the same circuit, it gets complicated. You don't want the car to be drawing 72A and then have the other thing try to draw 30.

If it's two Teslas, you can get two of the G2 chargers and daisy chain them. The first one is told it's on a 100A circuit and the second is told to follow. Either can use ~72A or whatever, unless they're both running. They'll negotiate for something that doesn't blow the circuit.

Your compressor won't do that. Budget for it.

I'm on a 60A circuit ("ought to be enough for anybody") but typically charge at like, 30-32A or something. It's typically plenty for me.