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Verifying breaker can handle charger

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Hello TMC member,
I recently ordered a model 3 and want to make sure my break can handle the additional breakers. It looks like there are extra slot available. Would it cause any problem if we added new 50 amp breaks to those slots or is there a maximum this panel can handle?

Also it seems that all i need to do is have my electrician install 2x50amp breakers.

Im very new to this and would like to know exactly what I need tell my electrician.
 

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The basic issue is that you need to know how much added load your panel can handle. That means you need a load calculation.

See Flasher’s FAQ in my sig for tons of details or google one on the internet but your electrician is really the best bet. Perhaps get a couple of quotes to be sure one isn’t just saying ‘upgrade the whole panel’ to get the work!
 
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You definitely need to get an electrician to come and give you some quotes. It looks as if you have a 100A panel with a couple of high current loads already, so you may not be extremely lucky.
How much do you drive in a day? 120V charging may be all you need.
 
Easy , what service is to house? 100 or 200 amp?
100 amp gets 50 amp breaker if you have double slot empty.
200 amp gets 100 or 80 amp breaker.
Um, no. The breaker for the EVSE is determined by how much power is available, what the car can use, what the EVSE can handle, and how much money one wants to spend. Making that decision solely on the main service capacity is very wrong. Plus, an 80 or 100A circuit won't really help a Model 3 owner.
 
That panel is already stuffed to the max. I'm betting the 20A 240v breaker sitting in the bottom of the enclosure came from the upper right, where that 20 / 50a tandem breaker is installed now. It looks like the 20A sides are still serving a 240v load, so that breaker isn't even appropriate unless both 20A sides trip together.

There's also what looks like disconnected thick gauge wires? And what's up with the breaker that's off in the lower left? And the white / neutral wire that just disappears behind the breakers?

Does that GFCI breaker still work properly? From the picture it looks like there's nothing hooked up to it.

I'd want someone qualified to go through that panel.

-J
 
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Sounds like more expenses. If I drive to and from work only I drive about 30 mile round trip, but I also work as realtor as a second job which requires me to drive all over town. How do I tell how many amps try service is?
 
Yes, like I said before have a qualified person look at what all is going on in your panel and advise you.

The right side of your panel is 100% full. Every breaker except 2 on the left are already doubles. Nothing I can type in a forum response box will change that ;)

You have 100 amp service.

-J
 
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Ninja also I recommend the HPWC unit it is safer and takes away a lot of the problems that multiple plug in connects that leave more possibility of heat or fire issues . You will only charge about 30 amps at 240V in the US or in EU either way .
 
I talked 2 different electricians and got 2 different answers. One says we may need to upgrade the other says I should be ok. Its like how you Kwat mentioned that dont use everything at once. On the breaker I have refrigerated air using 50amps, a dryer using 50amps as well, 50 amp for a range (but not in use, using gas to cook). Then I have the red and blue 15 or 20 amp through out the house.
 
I talked 2 different electricians and got 2 different answers. One says we may need to upgrade the other says I should be ok. Its like how you Kwat mentioned that dont use everything at once. On the breaker I have refrigerated air using 50amps, a dryer using 50amps as well, 50 amp for a range (but not in use, using gas to cook). Then I have the red and blue 15 or 20 amp through out the house.
If you're not using the 50 amp electric range. You could use that space (and capacity) for the charger.
 
You need a load calculation. You can give it a shot yourself using calculators on the internet. Both electricians I had look at mine did a load calc and I paid one of them for a copy of it. Then my brother-in-law electrician and I did the installation ourselves. There are specific assumptions the load calc makes about how different types of circuits are used, and takes into account each large load that is connected, it doesn't just add up the breakers. We had an unused 50A stovetop circuit I was able to replace with the HPWC 100A breaker. According to the load calc that filled up our entire 200A capacity.

If your electrician is guaranteeing the installation will pass the permitting inspection, has done a load calc, and says you're OK with the existing panel then I'd be happy to go with that.