220V vs 240V - need advice on new home build

redantpile

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Just curious if there was a reason you installed a 20 amp outlet versus a 50 amp outlet? I installed a 30amp in my garage when I purchased my Volt, a decision I have come to regret. I am not sure if I will make the change or just charge my R1S at

I was just putting in a couple of circuits for my tools in the garage. Table saw, compressor etc... At least 10 years ago and had no thought of charging an EV. I don't drive very much, and hope that this circuit will work for charging. I'm guestimating charging it 5 times a month on my driving habits.

If I was paying an electrician to install an outlet, then yes I would get the biggest circuit within reason. Upping the amperage is incremental at that point.

You might be able to upgrade your circuit for not too much trouble. Depends on what wire and/or conduit they used. If they used jacketed wire like 10/3(typical house cable) then maybe they could replace it with THHN and get another 10 amps or more.

But hey I'm not an electrician so so please consult a professional.





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McRat

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Today the spec is 120±5% vac at the service connection, so 240±5%
You will notice a drop in voltage under load.
 

CommodoreAmiga

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Today the spec is 120±5% vac at the service connection, so 240±5%
You will notice a drop in voltage under load.
If it's 120V±5% wouldn't it be 240V±10%?

Since 240V is measured between two 120V legs, 180 degrees out of phase from each other, the tolerances would stack.
 

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If it's 120V±5% wouldn't it be 240V±10%?

Since 240V is measured between two 120V legs, 180 degrees out of phase from each other, the tolerances would stack.
120±5% = ±6 vac
240±5% = ±12 vac

Stack up error happens with linear numbers.

That's why percentages are better to use than absolute numbers.

And why they tax us on percentage :mad:

Sidebar - The difference in voltage between the split phases of 240 means it's less likely to be at the Upper Control Limit or Lower Control Limit than a 120 line.

The Ultimate EV Home Charger would be 260 vac. The onboard charger has no problem with it.
Teslas will charge at a nominal 277 (commercial single phase from 480 3ph) which gives them an advantage.
 
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LeoH

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Basically it depends on the service coming to your house. Power companies will deliver 220 or 240 to your panel, and it splits to 2x110 or 2x120. I have yet to see an electric component that will not run on either voltage ( 110 and 120 or 220 and 240 ).

Its exactly the same, don't worry about it, especially that you probably can't control it :) Just make sure its 60amp. Amperes are the juice, Voltage is the pusher so its in your benefit to take 60amp irrelevant of the difference in volts between 220 and 240.
 

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Hello folks - I am building a new home and I have requested a 60A/240V circuit for my R1S. My builder keeps telling specifying a 60A/220V circuit. From an electrical perspective, I often see 220/240V called out. Should I insist on 240V or is it a distinction without a difference?

Thanks!
Obviously to me, your builder isn't an electrician.

If you are having a new house built in a new area, as opposed to an infill lot, it will have a 120/240 single phase service.

I am an electrician with over 30 years experience, the first 5 years doing strictly residential work. I've never encountered 220v in a house. I'm not saying that it isn't possible to have a 110/220 service, but that is only plausible if you were having the house built in an old neighborhood where the electric infrastructure is old too.

As others have said, people use the terms interchangeably and anything will work on either voltage, just better on 120/240v.
 

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