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Charging 2 Tesla’s on 100amp main - advice needed

Schedule 2 different charge times, or charge both cars together at a slower charge rate?


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Being in Cali you likely have superchargers handy for unexpected range needs.
Easiest thing might be as someone said above charge each every other night.
"best" IMO would be wall connectors on maybe a 60amp circuit, that way both cars can pull a decent amount at the same time and once the 3 is done the S can ramp up and top off fairly quickly.

I have a 7mile commute each way, got by on a 14-30 outlet(think dryer) one winter but still happy I did a wall connector on a 100amp circuit. I don't often need to use my car's 80amp capability but when I do I have it. but I have a 200amp service and shortly before swapped from baseboard electric heat to minisplits opening up capacity.

If you want to do both cars at the same time I would go smaller on at least one of the circuits like a 14-30 for the 3. I don't know why so many here seem to think 120volt or a 14-50 are the only options.
 
The safety of your family and your neighbors must come first. Your 100A panel is tiny. If you can afford 2 Tesla’s you can afford to do this right. 1) upgrade your electrical service to 200A. or 2) have a licensed electrician do your load calculation. Share a single wall charger between the cars. Pay the off tier electric cost. You can afford it.
 
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Upgrading the service to 200 amps is going to be prohibitively expensive, there is a gangable meterbase, and no easy way to reroute the wiring into the new panel, based on the images i saw.


In order to upgrade the service you would likely have to replace that gangable meterbase which is a huge huge huge project.

10K and up.

Those GE panels suck and if you do pull anywhere close to 100 amps on them, it’s only a matter of time before the bus fails.
 
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Two new cars and won’t buy wall chargers??

second am I the only one scratching my head why both outlets are on one side??

things just don’t add up here.
-2x performance cars
-worries about time of use hours
-wires in another socket by yourself
-doesn’t want to pay for wall chargers
-sounds like hesitation bringing our electrician

I’m either going to assume you got an inheritance or won a lotto ticket and spent every dime on two new performance cars as something doesn’t add up that you can spend $130k in cars but then not afford the proper wiring for them. Again I’ve said this before but being able to own something goes way beyond the cost of the car.. if I were you I would send the performance models back and actually afford to wire these cars up correctly. Do you really need to go so fast that you won’t use that power 99.99999% of the time and the. Have a sub par charging plan. This just doesn’t make any sense to me who chooses a car that’s one second faster and 10k more then skimps on electrician costs

totally call me out if you want. I was under assumption that a 100 amp panel actually could handle a 200 amp service if each 120 line is carrying 100 amps???

here’s the solution to all your problems. Get the electrician back out. And have him wire some wall chargers for Tesla sake. It’s 1k in wall chargers and you have what about 130k in new cars???

there is some very very smart people on here. But just call an electrician out and move on to other things. I’m not doubting you could actually get very correct info on here but it comes down to action and what you need is to call the electrician back out. Get the correct setup properly once and move on.

here’s what everyone has learned that saw the light and went as fast as possible. Less stress. Less worry. Less headache. Less fear. More happiness.

you have a limited time to charge. Two cars. Electric cars. Just go as fast as possible and never stress again. They will always be topped up no matter what
 
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Oh my goodness I wish I could put more than one disagree on your comment. There's barely anything correct in there!

Two new cars and won’t buy wall chargers??
doesn’t want to pay for wall chargers
have him wire some wall chargers for Tesla sake
What in the world is your obsession with wall connectors? Why do you seem to think that is some kind of magic potion that increases capacity? You are saying this as if you are certain that if these circuits terminated in wall connectors instead of outlets, it would be some kind of silver bullet that would solve all kinds of problems. They do no such thing. If this were two 30A circuit or 20A circuits, what kind of benefit do you think spending $1,000 on wall connectors would get? The answer is nothing. That is lighting $1,000 on fire.

second am I the only one scratching my head why both outlets are on one side??
They're not. Look at the picture again. Those two silver boxes side by side are where they come in through the garage wall. Then one runs along to near the garage door and has the outlet. Then see how the other conduit turns 90 degrees to go up the wall and then goes over the top of the garage doors along the ceiling? It is going across to the other side.

sounds like hesitation bringing our electrician
then skimps on electrician costs
Get the electrician back out.
But just call an electrician out and move on to other things.
what you need is to call the electrician back out
Jeez dude. He did get use an electrician--get over it. The problem that most of us are pointing out here is that the electrician he used gave him some terrible wrong information. The electrician said his 100A main service could handle having those two additional 50A circuits added to it, which seems really wrong. Your other point, I know, is that you think he should't have done the second outlet install himself after the electrician told him it would be fine within his existing service. That part I don't really get. Some people maybe shouldn't try that if they can't do it well, but if you look at that install picture, it looks fabulous, and I can't tell them apart, which one would have been the self-installed one, so it looks like he did a great job.

totally call me out if you want. I was under assumption that a 100 amp panel actually could handle a 200 amp service if each 120 line is carrying 100 amps???
:eek: No. That's not how that works. It is a 100A panel with a 100A feeder line. And it doesn't matter if they are 120V loads or 240V loads within that. It's still 100A total. If you have 100A coming in one hot phase and 100A going back out the other, that is a loop of a 100A circuit. You don't get to add together 100A on each phase line for 200A total.

here’s the solution to all your problems. Get the electrician back out. And have him wire some wall chargers for Tesla sake. It’s 1k in wall chargers and you have what about 130k in new cars???
OK, so I genuinely want to ask you about this, because you seem to think doing this will solve something. What do you think this will do? What would be accomplished with another electrician visit and $1,000 in equipment?

The very specific problem is that he just has a really small electrical service in his house, so he doesn't have much overhead to add very large circuits. Attaching wall connectors onto them doesn't magically make them have more capacity or make his main electrical feed bigger.

Upgrading the service to 200 amps is going to be prohibitively expensive, there is a gangable meterbase, and no easy way to reroute the wiring into the new panel, based on the images i saw.


In order to upgrade the service you would likely have to replace that gangable meterbase which is a huge huge huge project.

10K and up.
All right. I don't know this specific kind of setup too well, but I would have thought at least $5,000 to $6,000 for a service upgrade, which is why several of us are trying to figure out some compromise with 20 or 30 amp circuits or something to make this work within the existing small service.
 
Oh my goodness I wish I could put more than one disagree on your comment. There's barely anything correct in there!




What in the world is your obsession with wall connectors? Why do you seem to think that is some kind of magic potion that increases capacity? You are saying this as if you are certain that if these circuits terminated in wall connectors instead of outlets, it would be some kind of silver bullet that would solve all kinds of problems. They do no such thing. If this were two 30A circuit or 20A circuits, what kind of benefit do you think spending $1,000 on wall connectors would get? The answer is nothing. That is lighting $1,000 on fire.


They're not. Look at the picture again. Those two silver boxes side by side are where they come in through the garage wall. Then one runs along to near the garage door and has the outlet. Then see how the other conduit turns 90 degrees to go up the wall and then goes over the top of the garage doors along the ceiling? It is going across to the other side.






Jeez dude. He did get use an electrician--get over it. The problem that most of us are pointing out here is that the electrician he used gave him some terrible wrong information. The electrician said his 100A main service could handle having those two additional 50A circuits added to it, which seems really wrong. Your other point, I know, is that you think he should't have done the second outlet install himself after the electrician told him it would be fine within his existing service. That part I don't really get. Some people maybe shouldn't try that if they can't do it well, but if you look at that install picture, it looks fabulous, and I can't tell them apart, which one would have been the self-installed one, so it looks like he did a great job.


:eek: No. That's not how that works. It is a 100A panel with a 100A feeder line. And it doesn't matter if they are 120V loads or 240V loads within that. It's still 100A total. If you have 100A coming in one hot phase and 100A going back out the other, that is a loop of a 100A circuit. You don't get to add together 100A on each phase line for 200A total.


OK, so I genuinely want to ask you about this, because you seem to think doing this will solve something. What do you think this will do? What would be accomplished with another electrician visit and $1,000 in equipment?

The very specific problem is that he just has a really small electrical service in his house, so he doesn't have much overhead to add very large circuits. Attaching wall connectors onto them doesn't magically make them have more capacity or make his main electrical feed bigger.


All right. I don't know this specific kind of setup too well, but I would have thought at least $5,000 to $6,000 for a service upgrade, which is why several of us are trying to figure out some compromise with 20 or 30 amp circuits or something to make this work within the existing small service.


Just charge them at different times.... it takes about 4 hours to charge my model three from 20 percent to 90 percent so if you just schedule one to charge in the evening and start the other one to charge at around midnight you should be fine.

Your AC probably draws less than ten amps when running, the rest of your house less than 50 amps. Looks like you already got your panel open and had a looksy. If you are adventurous get a clamp meter and measure how much current you are actually drawing and then you know the car pulls a maximum of 32 amps. So as long as your house is pulling less than 50 amps right now your good to go. You can also adjust the charging current in the software of the car.

Technically adding two 50 amp outlets isn’t against the code. Adding two 50 amp EV chargers is, since EV chargers are a continuous load.
 
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