Question about Charging new Model 3

[subsonicone]

Picking up my model 3 Saturday, I have my home charger coming Monday and already have a 30A 220 receptacle in my garage about 10 ft from the door where I park.

Will 30A be suitable for 15-20 miles per hour of charge? I would hate to run new 8ga wire “builder installed 10ga and a 30A at 220v” and pop in a new breaker as this was already in place with my new one build.

Tesla model 3 standard range if that’s required.

 

[blackT3$!@]

already have a 30A 220 receptacle in my garage

I would watch this YouTube video from the Tesla Bearded guy on charging receptacles. If you don't have a high quality receptacle designed for sustained loads, you may pop your breaker or cause a fire.

 

[afadeev]

Picking up my model 3 Saturday, I have my home charger coming Monday and already have a 30A 220 receptacle in my garage about 10 ft from the door where I park.

Will 30A be suitable for 15-20 miles per hour of charge? I would hate to run new 8ga wire “builder installed 10ga and a 30A at 220v” and pop in a new breaker as this was already in place with my new one build.

Yes, it should be plenty. Those 30A 220 receptacle are usually build for high load electric drying application.
Most L2 EVSE on the market are designed to work with them, and have max current of right around 30Amps. A few EVSEs can support higher electric current flow rates, and you will need to dial them back to stay at below 30amps to avoid tripping the breaker.

I've used just such a setup for 10+ years and 3 EVs.
Works like a charm.
You will get 7.0-7.2 KWh of energy per hour, or ~10% of full battery capacity (assuming 70KWh battery in yours). It's easier to measure battery depletion and charging as % of total, as mileage estimates are wildly inaccurate from Tesla, and very a lot depending on your driving habits and ambient temps. Upto a factor of 2.

HTH,
a

 

[FastEddieB]

Will 30A be suitable for 15-20 miles per hour of charge? I would hate to run new 8ga wire “builder installed 10ga and a 30A at 220v” and pop in a new breaker as this was already in place with my new one build.

I charge our M3LR daily from a 30A receptacle - in my case an L14-30. It yields roughly 23 miles of range per hour.

Everyone‘s use case is different, but that speed is enough to top back up to 80% in just a few hours even if our daily errands run to 100 miles - which they very rarely do.

 

[Benito1283]

You'll be fine with the charging speed. Like the first response said, you will want to upgrade the receptacle to something like the Hubbell HBL9430A. A Leviton (what's most likely there now) is fine for a dryer since it's not a continuous load. It's a gamble for EV charging though.

 

[mirkop82]

My understanding is that for continuous loads you should not exceed 80% of the nominal capacity of the circuit.
I’m also using a 30A plug and to be safe I set the max Ampere drawn by the charger to 24A (roughly 20 miles charged per hour).

 

[Technokrat]

Hmm I thought you are supposed to charge at 80% of the rated Amperage meaning for a 30A power supply the max charging would at 24A and not 30A. I charge at 32A with a 40A supply.

 

[E90alex]

Are you installing a wall connector in place of the receptacle?

30A circuit is fine on 10 awg wire. It will charge at 24A due to the 80% rule.

 

[ucmndd]

Use what’s already in place. It will be plenty.

 

[ucmndd]

I charge our M3LR daily from a 30A receptacle - in my case an L14-30. It yields roughly 23 miles of range per hour.

Whatever you’re doing, you’re doing it wrong. You should not be drawing any more than 24 continuous amps from a 14-30 receptacle (and your charging equipment should enforce this).

Also, 183 volts is critically low for a 240v circuit, and dangerously low even for a 208v supply. Something is not right.

 

[FastEddieB]

Whatever you’re doing, you’re doing it wrong. You should not be drawing any more than 24 continuous amps from a 14-30 receptacle (and your charging equipment should enforce this).

Also, 183 volts is critically low for a 240v circuit, and dangerously low even for a 208v supply. Something is not right.

You’re right. Seeing the location, “Woodlawn Rd.”, that’s not my home and I don’t recall where that was or what receptacle/adapter I was using at the time. At home I do see 24A charging from my L14-30 adapter and 23 miles of range per hour.

 

[ucmndd]

You’re right. Seeing the location, “Woodlawn Rd.”, that’s not my home and I don’t recall where that was or what receptacle/adapter I was using at the time. At home I do see 24A charging from my L14-30 adapter and 23 miles of range per hour.

That’s reassuring.

I’ve come across a number of public j1772 chargers that provide 30 amps like that on 208v service. Sometimes they have very low voltage at the end of a long run.

 

[subsonicone]

Sorry for the lack of details on the electrical side, recovering from a 16yo crossing 3 lanes and a median to Tbone me while letting my wife’s car stop her “she didn’t touch her brakes” I’ve been having difficulty driving my manual transmission in my truck so my wife surprised me with this car as she knows spinal surgery is in my future now.

Anyhow it’s a legrand 14 50R and using a home charger “portable one” as it was free. It’s 8’ from my panel in the garage and was installed by the builder using 10ga THNN on a 220v 30A squareD “HOM” style breaker. They Installed 220 30A service as most people were asking for a interlock kit for a generator. So in their awesomeness they did this to every home and used the top right breaker spot. I had a whole house NG generator installed so I am using this spot for my charger now since it’s a dead circuit and I only have to remove the 3 screws for the interlock kit.

I can easily run some 8-6ga and pop in a 40A and not pull too much as my home is mostly gas. I just figured this is easier for now with my injury and if we go on a trip we will take her new palisade anyway.

Thank you for all the replies!

 

[Jordan325ic]

In my opinion new EV drivers way over-estimate their charging needs. Nobody except maybe a full-time Uber driver actually needs to be able to do a full 1-100% in 8 hours. Even on the odd occasion where maybe you take a road-trip and get home with a low state of charge, are you really going to be doing another giant road trip the very next morning? Contrary to popular belief, you don't actually need 100% state-of-charge to pop out to get groceries.

We do 400 miles per week in my house and we got by just fine on a regular wall socket while I waited for an adapter. Now we have a luxurious 30A/120V RV outlet adapter and I don't even bother to plug it in some nights. The 3 RWD is just so crazy efficient.

To me your wall outlet sounds like it will be more than enough. 100% I think if you use it for a few weeks you will forget about upgrading.

And if you're at all worried about the outlet quality, as mentioned above, just turn down the amps on the charging screen or on the app. Even at 1/2 power I bet that outlet will still be plenty.

 

[RayK]

Picking up my model 3 Saturday, I have my home charger coming Monday and already have a 30A 220 receptacle in my garage about 10 ft from the door where I park.

Will 30A be suitable for 15-20 miles per hour of charge? I would hate to run new 8ga wire “builder installed 10ga and a 30A at 220v” and pop in a new breaker as this was already in place with my new one build.

Tesla model 3 standard range if that’s required.

I don't believe that this has been mentioned up to now, but your SR will only be able to Level 2 charge at a maximum of 32A by design (your car only has two 16A charger modules). Doing anything to change your external electrical connections and/or charging equipment, will not affect your ability to get any more than 32A. So, for your case, going to a 50A breaker / outlet combination to get what would be a normal maximum of 40A continuous, will still be limited to 32A actually getting into your car. Yes, that's better than the 24A you would be getting with a 30A circuit; somewhere around 8 more miles per hour when charging.

 

[subsonicone]

I don't believe that this has been mentioned up to now, but your SR will only be able to Level 2 charge at a maximum of 32A by design (your car only has two 16A charger modules). Doing anything to change your external electrical connections and/or charging equipment, will not affect your ability to get any more than 32A. So, for your case, going to a 50A breaker / outlet combination to get what would be a normal maximum of 40A continuous, will still be limited to 32A actually getting into your car. Yes, that's better than the 24A you would be getting with a 30A circuit; somewhere around 8 more miles per hour when charging.

This was my understanding as well on the 32A max but i also read somewhere that they changed it to three 16A charger modules “48A” like the long range. Mabye I’m wrong and it was miss information that I read . Either way it’ll be fine for my purpose and I appreciate the info as the max amp was a question I was going to ask in person on Saturday when I pick it up.

 

[puckpurnell]

Think about a 50 amp line if you can. It will bring the charging rate up to about 29 mph.

 

[jjrandorin]

This was my understanding as well on the 32A max but i also read somewhere that they changed it to three 16A charger modules “48A” like the long range. Mabye I’m wrong and it was miss information that I read . Either way it’ll be fine for my purpose and I appreciate the info as the max amp was a question I was going to ask in person on Saturday when I pick it up.

The model 3 RWD / SR only has (2) 16amp charger modules in it, so 32amp charging. There is a thread here, however, where someone needed to get their car repaired, and then found out after the repair, their SR+ / RWD car charged at 48amps. Perhaps you are remembering that thread.

In any case, while I have read a couple of people say that (repaired PCS on a SR+, ended up with 48amp charging on a SR+ car) that should be viewed as a 1 off situation, as I have not even seen people be able to request such in a retrofit, let alone new SR+ / RWD vehicles coming with faster charging.

TL ; DR = your car should be capped at 32amp, as that is normal for that car, and to be expected.

 

[DuncanM]

Sorry for the lack of details on the electrical side, recovering from a 16yo crossing 3 lanes and a median to Tbone me while letting my wife’s car stop her “she didn’t touch her brakes” I’ve been having difficulty driving my manual transmission in my truck so my wife surprised me with this car as she knows spinal surgery is in my future now.

Anyhow it’s a legrand 14 50R and using a home charger “portable one” as it was free. It’s 8’ from my panel in the garage and was installed by the builder using 10ga THNN on a 220v 30A squareD “HOM” style breaker. They Installed 220 30A service as most people were asking for a interlock kit for a generator. So in their awesomeness they did this to every home and used the top right breaker spot. I had a whole house NG generator installed so I am using this spot for my charger now since it’s a dead circuit and I only have to remove the 3 screws for the interlock kit.

I can easily run some 8-6ga and pop in a 40A and not pull too much as my home is mostly gas. I just figured this is easier for now with my injury and if we go on a trip we will take her new palisade anyway.

Thank you for all the replies!

That outlet should not be used except with a 50amp breaker and the appropriate wire size from the panel.

You should use a quality NEMA 14-30 outlet to match the installed breaker and wire size, and the NEMA 14-30 adapter cable for your Tesla Mobile connector; this will automatically limit amperage to 24a and that will provide about 5kw to the car, or about 20 miles of range per hour of charge.

I would highly recommend having at least two mobile chargers as one should remain in the car at all times for emergency use on the road.

 

[Rocky_H]

Anyhow it’s a legrand 14 50R and using a home charger “portable one” as it was free. It’s 8’ from my panel in the garage and was installed by the builder using 10ga THNN on a 220v 30A squareD “HOM” style breaker.

Holy freaking cow. That's terrible.

So in their awesomeness they did this to every home and used the top right breaker spot.

(sarcasm on) Oh, well that's lovely for them to deploy that defect to every home.

They put a 50A outlet type on a 30A circuit with only 30A rated wire. What were they thinking? That should get replaced with a 14-30, and then you buy the Tesla 14-30 plug, and it will enforce the amps properly.

I'm not mad at you, but frustrated with such a bad choice from the builder.