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Difficult situation with a Condo, advice appreciated...

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I think you're misunderstanding why people are suggesting that. It's nothing to do with cheaper wire, or even anything related to just that specific line for the charging circuit itself. This is about the fact that it is more likely that you can probably fit an extra 20A circuit into your EXISTING main service that your apartment has. If you go much bigger than 20A or maybe 30A, it's very likely that you have to increase the entire main feed to your apartment, which costs several extra thousand dollars.

Oh okay, I see. I was likely going to be getting 20A service, even if I get the Tesla Wall Connector. Due to my power company rebate for L2 EVSEs, it's basically free for me. And my hope is to install as big of a breaker as code will allow for (maybe 30A), since the marginal cost is probably not that different, even if I just soft-limit it to 20A to be extra safe anyway. No matter what I do, I'm going to avoid upgrading the main feeder wiring, even if it leaves me with a 20A Tesla Wall Connector.

I agree with a 20A 240 volt circuit, but for tax and reliability reasons I suggest hard wiring it to a fixed Tesla or J1772 based station. I mention J1772 station because you may not always own a Tesla, and it is nice not to be locked into a brand based on previous investment. Either way, yes labor is going to be high, but just running a 20A 240V to a hardwired station makes this easy.

I think the reason I'm going with the Tesla unit is because it's software reconfigurable and costs exactly $500, which is exactly what my electric company rebate is.

Also, the number labels on your breakers are put on wrong and it is driving me nuts! The 240V AC breaker is actually in slots 6 and 8, but it is labeled 11 and 12, which is why the diagram written on the door doesn't match up very well with the actual breakers. It is just bugging me!

Lol yeah. That was bugging me too!

Based on your loads you have limited draw, and I would speculate that the resistance heat strips aren't connected presently. Others have covered how split phase works so I won't rehash that but your PC, fridge, microwave might draw 20 amps total at 120V (10A at 240V) and they are intermittent loads. Your AC probably draws 10A at 240V. My 3 ton unit only draws 14A and it was installed 20 years ago. Allowing for surge current is a thing with motors though, so call it 20A for rating purposes.

I see you having about 30A of load, so long as it's reasonably balanced you could go with a 30A charging station which would draw 24A, bringing you to 54A. That is still a ton of headroom.

If you want to get more precise we will need more data like square footage, if you have a garbage disposal or not and I could do a proper load calculation.

This is all really insightful. I appreciate it! Here's the extra data for you: 650 sq. ft. condo unit. No trash compactor of any kind. I have a dishwasher. I also have a clothes washer and gas dryer unit.
 
Even if you did trip the breaker well so what? You can switch it back on and upgrade it when you have evidence it’s necessary.

Well, there's kind of the reason I'm overthinking all of this. I do not have access to the electrical room where my main breaker is. The janitorial service is the one who needs to unlock it for me. So if I trip my main breaker, I'm without power for potentially a day or two, depending on how easily I can get hold of the janitor. So I am *really really* interested in making sure I don't trip that main breaker.

In fact, after I get it all installed, I plan to I test everything out completely and know what the limits are while the electrical room is still unlocked.

I agree with the idea to run heavier wire regardless. At the very least, I ever decide to add a DCC unit then I might be able to increase the size of the breaker.
 
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Based on the load calculation I would suggest you could have 16A charging on a 70A main.

Your best bet is to check if you have a smart meter, and then get the historical data from the utility. Smart meters don't have spinning dials, but do have digital displays, and are VERY common. Once you have that data and find the peak over a year then we can figure out what you can actually have per previously mentioned formula. In the NEC code there are three ways to calculate correct service size per a load, and the best case for your situation is hope that your actuals are low enough to allow the additional.
 
If you can run your washer dryer while your AC is on, you can put a 30 amp breaker on your panel and charge your car at about 21 miles per hour of charge. Just don't use your washer dryer while charging the car.
And THIS is why we can't have nice things!

while 15+15 is indeed 30, because the washer and dryer are each 15 amp 120V circuits, not using them would only allow the theoretical addition of a 15 amp 240 volt circuit.. Even that is assuming the washer and dryer are using different legs of the 240 line, and also presumes that they are both using 100% of that 15 amps, since you know for sure that the EV charger will be using the full capacity(actually 80%) of whatever it is handed, for hours at a time.
 
And THIS is why we can't have nice things!

while 15+15 is indeed 30, because the washer and dryer are each 15 amp 120V circuits, not using them would only allow the theoretical addition of a 15 amp 240 volt circuit.. Even that is assuming the washer and dryer are using different legs of the 240 line, and also presumes that they are both using 100% of that 15 amps, since you know for sure that the EV charger will be using the full capacity(actually 80%) of whatever it is handed, for hours at a time.
Actually the clothes washer and clothes drier share a 20A 120V circuit.
 
Based on the load calculation I would suggest you could have 16A charging on a 70A main.

Your best bet is to check if you have a smart meter, and then get the historical data from the utility. Smart meters don't have spinning dials, but do have digital displays, and are VERY common. Once you have that data and find the peak over a year then we can figure out what you can actually have per previously mentioned formula. In the NEC code there are three ways to calculate correct service size per a load, and the best case for your situation is hope that your actuals are low enough to allow the additional.
And THIS is why we can't have nice things!

while 15+15 is indeed 30, because the washer and dryer are each 15 amp 120V circuits, not using them would only allow the theoretical addition of a 15 amp 240 volt circuit.. Even that is assuming the washer and dryer are using different legs of the 240 line, and also presumes that they are both using 100% of that 15 amps, since you know for sure that the EV charger will be using the full capacity(actually 80%) of whatever it is handed, for hours at a time.

Ah man it's looking pretty dire all of a sudden... I would go and check for a smart meter but sadly I don't have access to the electrical room right now. :(

Perhaps this is the point where we figure a DCC-12 unit might be worth brining into the mix? Expensive, but if it lets me get around the load-calc limit then maybe it's okay?

EDIT: Whoops, I read "couldn't have 16A charging". I can live with 16A charging if that's all that can fit according to NEC. A 30A breaker *would* be nice, but it's not worth an extra $1000 for a DCC. I might just have to sit tight with a 20A circuit.
 
Ah man it's looking pretty dire all of a sudden... I would go and check for a smart meter but sadly I don't have access to the electrical room right now. :(

Perhaps this is the point where we figure a DCC-12 unit might be worth brining into the mix? Expensive, but if it lets me get around the load-calc limit then maybe it's okay?

EDIT: Whoops, I read "couldn't". I can live with 16A charging if that call that can fit according to NEC.
Check your electric company website and see if your account shows daily/hourly usage. If so, then you have the data at your fingertips. If your all LED lighting your peak likely to be half the calculated, which would allow you to go to a 30A circuit.
 
Check your electric company website and see if your account shows daily/hourly usage. If so, then you have the data at your fingertips. If your all LED lighting your peak likely to be half the calculated, which would allow you to go to a 30A circuit.

I do have all LED lighting here. Not a single incandescent or CFL. As for my power company website, this is all they offer to me. Nothing hourly at all!

Screen Shot 2021-04-09 at 12.35.16.png
 
I just came upon this thread, read the first few messages & then skipped to the end, so forgive me if I didn't notice if someone else has already suggested this. You're living in L.A. where there are a ton of Superchargers – so why not just make use of them when you need to juice up? It's not like you were in a part of the country that has lousy weather – duh, cold or REALLY cold winters. How far is the nearest S.C?
 
I just came upon this thread, read the first few messages & then skipped to the end, so forgive me if I didn't notice if someone else has already suggested this. You're living in L.A. where there are a ton of Superchargers – so why not just make use of them when you need to juice up? It's not like you were in a part of the country that has lousy weather – duh, cold or REALLY cold winters. How far is the nearest S.C?

Well, that's what I'm doing right now until I have this all sorted. There are plenty of them, I agree, but for me the dream of owning this car is that I basically never have to "fill up"; my car is just always ready to go. Also, in SoCal we have a lot of Teslas and so the SCs do actually get full. My nearest one, 5 minutes away, is completely full about half the time I check on it.
 
You're living in L.A. where there are a ton of Superchargers – so why not just make use of them when you need to juice up?
Heh. Well, you're from Cincinnati, so I think you are mixing two paradigms. You are familiar with having less Superchargers around you, but seeing them mostly empty most of the time. Yes, L.A. has a ton of Superchargers, but they have more than a ton of Teslas, so they are full and frequently have waiting lines. That is probably not going to be a fun and convenient way to own an electric car, versus always having consistent home charging. Plus, L.A. traffic just to go to a Supercharger would suck.
 
I do have all LED lighting here. Not a single incandescent or CFL. As for my power company website, this is all they offer to me. Nothing hourly at all!

View attachment 652401
Average Daily usage isn't the best metric, but if we divide that by 24 we get less than 1KW except in the summer where you ever so slightly exceed 1KW.

Let's do some math.

The lowest period is probably no AC at all, so that is your base, fridge, computer laundry etc. YOU didn't go on an a long vacation in the Jan 29th to Mar 27th did you? If not then we can safely assume you are averaging 15.74 KWH per day. This doesn't tell us your peak exactly, but if we assume you used it all in 4 hours (which would be insane as your fridge would only run during those 4 hours) by doing everything at once, laundry, cooking, dishes, computing, TV, etc. then we have a draw of about 4KW. 4KW / 240V = 17 amps. We add in the AC worst case of 20A and we have 37A. We add 24A for car charging and you get to 61A.

This calculation above wouldn't satisfy a serious NEC reading inspector, however I can say that you should be fine to do a 30A circuit based on it. You should contact your electric utility to get the peak 15 minutes of usage for the last year (or as granular as they can give you). With that data you can substantiate my guess work above and get approval to put in a 30A station.
 
I just came upon this thread, read the first few messages & then skipped to the end, so forgive me if I didn't notice if someone else has already suggested this. You're living in L.A. where there are a ton of Superchargers – so why not just make use of them when you need to juice up? It's not like you were in a part of the country that has lousy weather – duh, cold or REALLY cold winters. How far is the nearest S.C?
Supercharging probably isn't free for the OP, and for the long term installing a station at home is going to pay for itself. Also tax credits and all that help that along a bit.

I will also say I hate going to the gas station
 
You mean like the 3mi/hr 110V trickle charge? I suppose I could get away with it since my commute is short, but I'd prefer to have a bit more. My thinking is that if I'm going through the expense of running new cables, I would like the idea of coming to a 80% charged car every time I get in.
Nana. I recently purchased a model 3 long range and using are my 115 outlet my car charged at 6 miles per hour. Finally my wall charger has been installed. Haven’t charged my car yet but will do it tonight.