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I'm getting my I4 M50 in a few weeks (at port in germany shipping to NJ USA) and its my first electric car. I want a level 2 charger for my house but im not sure about the best setup(purchasinga Charge Point). My goal is the highest amps for quickest charge. My question is how many amps should i tell my electrician i need? Whats recommended for the car? Not sure if im asking that question the right way or not. I know it depends on the panel but lets assume i have one that can support the highest power levels.
 

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If you plug in the Charge Point, it will be 40 amps charging (need 50A breaker). If you hardwire the Charge Point, it will be 48 amps (need a 60A breaker). I personally went the plug in route as it is plenty fast for an overnight charge but hardwired would be the fastest.

Edited to clarify charging rate and breaker needed.
 

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If you hardwire, you will need a 60A breaker to use the chargepoint 50 or 48. They charge 37 miles an hour. If you want the NEMA 14-50 outlet, then its the charge point 40 Which charges at 30 miles per hr. You will need a 50A GFCI breaker ( as per the 2020 NEC code). But the irony is almost all EVSE manufacturers advise you to NOT put in a GFCI breaker. Its a catch 22
 

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I suggest you check with your electrician to see how big a breaker you could put in your box first. As for L2 charging we've always used the OEM chargers that come with the vehicles and they charge overnight.
 

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2021 Mach E (i4 M50 on order)
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I'd recommend going with at least a 50A circuit. Your electrician will tell you whether your current breaker panel can support it (if you have a 200A panel, you'll be fine; if you have a 100A panel (as many older homes do), you might need to add a second meter for a separate feed. In any case, your electrician will give you the best options.

A 50A circuit (40A charging) is as much as anyone really needs, especially if your charging is done at night. 48A charging is nice if you come in late with 0% SOC and need to be at 100% for an early morning departure, but this almost never happens to any normal person.

Be sure to keep your receipts; there is a federal tax credit for electrical upgrades to support an EV (IRS Form 8911). I got nearly $800 back on my taxes for my electrical work. Also, many local utility companies have a rebate program for installing the home charger units (my local utility gave me $500 back). In all, I got nearly $1,300 towards my electrical investment from tax credits and utility rebates.
 

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I'd recommend going with at least a 50A circuit. Your electrician will tell you whether your current breaker panel can support it (if you have a 200A panel, you'll be fine; if you have a 100A panel (as many older homes do), you might need to add a second meter for a separate feed. In any case, your electrician will give you the best options.

A 50A circuit (40A charging) is as much as anyone really needs, especially if your charging is done at night. 48A charging is nice if you come in late with 0% SOC and need to be at 100% for an early morning departure, but this almost never happens to any normal person.

Be sure to keep your receipts; there is a federal tax credit for electrical upgrades to support an EV (IRS Form 8911). I got nearly $800 back on my taxes for my electrical work. Also, many local utility companies have a rebate program for installing the home charger units (my local utility gave me $500 back). In all, I got nearly $1,300 towards my electrical investment from tax credits and utility rebates.
Generally agree with what you said, although I did run a 60A line to support 48A hardwired charging. It was a personal choice as wire size wasn't a big factor and with hardwire, I could avoid the need for a GFCI and a neutral.

Please note that credit claimed on form 8911 expired. It's only good for installations up to the end of 2021. From the Instructions for form 8911, under whats new: "The alternative fuel vehicle refueling property credit expired for refueling property placed in service after 2021. Do not report refueling property placed in service after 2021 on Form 8911 unless the credit is extended." Any legislation extending the credit could potentially mess up the $7,500 credit for purchase of the EV. As my hardwired 48A charger only cost me $710 to install (credit would have been only 30% of that) the full EV credit is much more attractive to me. If you installed the charger in 2021 and bought the i4 in 2022, you get the best of both worlds.
 

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I'm getting my I4 M50 in a few weeks (at port in germany shipping to NJ USA) and its my first electric car. I want a level 2 charger for my house but im not sure about the best setup(purchasinga Charge Point). My goal is the highest amps for quickest charge. My question is how many amps should i tell my electrician i need? Whats recommended for the car? Not sure if im asking that question the right way or not. I know it depends on the panel but lets assume i have one that can support the highest power levels.
Wire everything for 100 amps. Then get a 48 amp charger. When and if your next EV takes 80 amps, you can get a new charger.
 

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Wire everything for 100 amps. Then get a 48 amp charger. When and if your next EV takes 80 amps, you can get a new charger.
That's making the assumption that the technology roadmap travels in the direction of higher power home charging. Sometimes, these roadmaps show a point that says "new invention" and the date and specifics are unknown. I seem to have lost my "approved" copy of the roadmap, broke my crystal ball and my turban is at the dry cleaners😀. I'm a fan of robust design for incremental improvement, but don't try to get too far ahead, as things change.
 

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That's making the assumption that the technology roadmap travels in the direction of higher power home charging. Sometimes, these roadmaps show a point that says "new invention" and the date and specifics are unknown. I seem to have lost my "approved" copy of the roadmap, broke my crystal ball and my turban is at the dry cleaners😀. I'm a fan of robust design for incremental improvement, but don't try to get too far ahead, as things change.
I expect 80 amp chargers will eventually be the norm. Plus having a 100 amp line allows two 40 amp chargers, if that's the way a person chooses. Me? I did two 50 amp runs, and that's plenty good for me. The hottest charger I have is 32 amps, and I've never said, "Gee, I wish this was faster." Ever.
 

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I expect 80 amp chargers will eventually be the norm. Plus having a 100 amp line allows two 40 amp chargers, if that's the way a person chooses. Me? I did two 50 amp runs, and that's plenty good for me. The hottest charger I have is 32 amps, and I've never said, "Gee, I wish this was faster." Ever.
Well, the J1772 standard does support up to 80A (19.2kW) so no new invention would be needed. just a new car.
 

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2021 Mach E (i4 M50 on order)
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One of the benefits of 80A is for bi-directional electricity usage (as is starting to happen with newer, larger EVs, like the F150). With the right hardware, your car(s) can fully power your home if the grid goes dark. I don't have a personal need for this, but for those who live out in the country and who have more frequent power disruptions, it may be desirable to set up for 80A. I wouldn't be surprised if bi-directional becomes more popular, especially if power companies begin to think of the collective storage in EV batteries as grid storage.
 

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One of the benefits of 80A is for bi-directional electricity usage (as is starting to happen with newer, larger EVs, like the F150). With the right hardware, your car(s) can fully power your home if the grid goes dark. I don't have a personal need for this, but for those who live out in the country and who have more frequent power disruptions, it may be desirable to set up for 80A. I wouldn't be surprised if bi-directional becomes more popular, especially if power companies begin to think of the collective storage in EV batteries as grid storage.
Interesting. My home usage is around 30kWh/day, so I could get a couple of days out of a fully charged car while still leaving enough charge for a short trip if the power wasn't restored.
 
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