Which plug do I need for full 32A Charging?

[torpy]

Hi All,

Future Tesla owner here trying to figure out exactly what plug setup I need to take advantage of full 32A charging using the Mobile connector. From all my research it sounds like 14-50 would be the only option right? Is there a lower amperage setup that would allow me to charge at 32A safely? What is the max safe charge rate if I had a 14-30 with 30A breaker?

Been doing a lot of research but looking for some guidance from the folks here

PS> My breaker box is currently full. Is it ok to clear out 2 slots of 15A breakers to make room for a 50A breaker? 100A service

 

[Sophias_dad]

Lets see....

Regardless of breaker, the UMC/Tesla will only ever take 32 amps continuously, so it doesn't matter if you put a 40 or 50 amp breaker and appropriate wire going to that 14-50 plug.

You can also use a 6-50 plug if you like. I'm not sure of the rules regarding a 6-50 outlet on a 40 amp circuit, but I imagine its fine since the same rationale that allows the 14-50 on a 40 amp circuit would apply to the 6-50.

If you use a 14-30 plug and associated 30 amp breaker, the UMC will allow a 24 amp charge. The adapter that connects the 14-30 outlet to the UMC will actually tell the UMC what its type is, so you don't need to reset the amperage in the car.

Taking 32 amps continuous off a 100 amp panel that's stuffed may well be more than the main breaker will take. You need to do a load calculation.

Depending on your panel type and breakers, you may be able to put in a few 'tandem' breakers that put two breakers in one spot. Its also theoretically possible to combine circuits to some degree, but you need to be a little careful about what you combine, to keep from causing nuisance trips.

 

[Ken_Y]

I had the same problem and upgraded my panel to get up to 200A from 100A.

 

[Gauss Guzzler]

It's usually fine to add a 50A breaker even though your main is only 100A, and it's usually fine to consolidate circuits onto tandem breakers to make room. Verify with the breaker panel label and load calculations. If you can legally install it, give it a shot. Then adjust your charging habits as needed if you're bothered by nuisance breaker trips.

Cheapest option is a 6-50 outlet on a 40A circuit. You only get 80% of the circuit capacity but that works out to exactly the 32A you wanted.

Cheaper is a 14-30 which limits you to 24A, but that's still ample unless your driving or sleeping patterns are very unusual.

 

[torpy]

Thank you all for your guidance and input. I think I might just go with 14-30. 24A should be plenty fast over normal 120v

 

[Frank99]

Most new owners vastly overestimate the amount of charging they need at home. There have been days when I got home late with less than 5% charge remaining, and needed to go to work the next morning. But that’s never been an issue - 6 hours at 30 miles per hour of charging is 180 miles of range in the morning which is plenty, even though charging hadn’t completed.

 

[sunfarm]

DCC-10 | Charge controller for electric vehicles | RVE

The DCC-10 is an Electric Vehicle Energy Management System that allows a charger to be connected directly to an electrical panel at full capacity.

dccelectric.com

Don't need nothing upgrade.

 

[Sophias_dad]

DCC-10 | Charge controller for electric vehicles | RVE

The DCC-10 is an Electric Vehicle Energy Management System that allows a charger to be connected directly to an electrical panel at full capacity.

dccelectric.com

Don't need nothing upgrade.

Yes, nothing except for $1000 plus installation. I'd consider it a solution of last resort, and depending on the house/owner and its future I'd consider upgrading the panel and feed to 150-200 amps instead of buying a DCC-10(or DCC-9). I'd also want to try living with even 12 or 24 amp charging first.

 

[brulaz]

Thank you all for your guidance and input. I think I might just go with 14-30. 24A should be plenty fast over normal 120v

14-30 is 240V, not 120V, doubling your wattage.
Or perhaps you just meant rather than 120VAC at 15A. My bad ....

 

[sunfarm]

Yes, nothing except for $1000 plus installation. I'd consider it a solution of last resort, and depending on the house/owner and its future I'd consider upgrading the panel and feed to 150-200 amps instead of buying a DCC-10(or DCC-9). I'd also want to try living with even 12 or 24 amp charging first.

Sure good luck. I don't know how much in US ,but in Canada upgrading service (panel and feed) cost between $ 6K-10K, for me this is DCC box and ChargePoint charger + installation cost $2.5K. So I don't need anymore worry about upgrades my feed panel (125A), I have 50A brk and 9.6kw speed charge- for me more than enough. Of course it's depends what you want.

 

[sunfarm]

14-30 is 240V, not 120V, doubling your wattage.
Or perhaps you just meant rather than 120VAC at 15A. My bad ....

That's how fast you car will charge.

 

[FrankQ]

Btw guys I won’t recommend the 14-50 approach, the new code requires a gfci breaker which costs $100 for a 14-50 NEMA for EV charging, which creates frequent false tripping due to double gfci given Tesla itself also have a gfci mechanism;

 

[Gauss Guzzler]

The GFI is fine and doesn't cause nuisance trips. I suspect that rumor came from people seeing Tesla's advice not to install an unnecessary GFCI on wall chargers. Nuisance trips are usually caused by loose/corroded connections at the breaker.

But your argument is still strong. The GFI costs about $100 *more* than a standard breaker, plus you need a $40 outlet, $20 box/cover, $30 wall mount/cord hook, $35 pigtail adapter, and 50% more copper (neutral wire). Whereas a wall charger needs none of those things so the total cost is only about $200 more than a 14-50 and you get to keep your portable charger in the car for other uses!

 

[FrankQ]

The GFI is fine and doesn't cause nuisance trips. I suspect that rumor came from people seeing Tesla's advice not to install an unnecessary GFCI on wall chargers. Nuisance trips are usually caused by loose/corroded connections at the breaker.

But your argument is still strong. The GFI costs about $100 *more* than a standard breaker, plus you need a $40 outlet, $20 box/cover, $30 wall mount/cord hook, $35 pigtail adapter, and 50% more copper (neutral wire). Whereas a wall charger needs none of those things so the total cost is only about $200 more than a 14-50 and you get to keep your portable charger in the car for other uses!

And don’t forget you can get federal tax bonus on the wall charger

 

[Gauss Guzzler]

Yes, a federal tax credit will reimburse you for 30% of the cost of any property you place in service at your main residence for the purpose of EV charging, which doesn't just include wall chargers, but also outlets, pigtail adapters, cord hooks, portable chargers, or anything else you "place in service" for that purpose. The credit is capped at $1000 so it only applies to the first $3,333.33 spent and excludes the cost of permits but it does cover diesel refueling systems in case you're that guy and want to show the world how many F's you really give.

Many states offer EVSE credits/rebates that can be stacked with the Federal credit but they may only cover wall mounted units and many programs specifically state that only non-Tesla products are eligible.

But yeah, my argument above that Tesla's Wall Connector might only cost $200 more than a 14-50 outlet is referring to the pre-tax cost. After the 30% credit it might only be $140 more.