I know that in the US they find that their 120V supply inadequate especially when an EV is parked in the garage.
Do the EV charge station installers here install a 3 phase supply to your home (if there was only a single phase supply)?
The trouble is that those 120V sockets are only really rated for 15A max, and not continuous, usually you have to stick to 80% of that for longer periods, which is 12A, which means an EV can charge at max 1.4kW from an ordinary socket.
Here in South Africa, our old BS546 sockets are rated 16A, so again by the 80% rule we end up with very similar charge currents, but double the voltage. So even from an ordinary socket you can charge at a good 2.5kW, which overnight will give you easily an extra 100km of driving. So really not a big deal unless you drive further than that.
No. Because you can charge up to 7kW single phase with most EVs, which is 30A, and most houses can handle that just fine, especially after hours.
My EVSE is set to 24A max. That is because the wiring is 4mm^2, so it has to be protected by a 30A breaker, and the 80% rule thus caps me to 24A. That means the car can charge at 5.5kW, which means 100km of range every 3 hours.
Most EVs will charge at 11kW from a three phase supply (16A per phase). In other words, upgrading to three phase doesn’t add much speed.
If you need to charge faster than 11kW, you have to use a DC fast charger.
Slightly OT for this thread, but this explains very well why we don’t need all those terribly large chargers at home.
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Basic AC EV chargers can charge up to 32A per phase. Around 7kW on 1 phase, or 22kW on 3 phase.
BUT very few EVs in SA support 22kW AC charge. Most have a 10kW or lower limit. So there is very little gain in going to 3 phase (unless you have a high-end Merc/BMW).
Even then, 7kW will fully charge most EVs overnight, so still probably not an issue.
Great!
There’s much discussion about Amps but not of voltage.
I presume that DB board at his parent’s home is supplying from a phase to phase connection (210V) ??
Despite what most of us might have heard, North America is a 240V country. Most of the new parts anyway. To be backwards compatible, they put a tap halfway on the transformer, which becomes their neutral, and is also bonded to earth. That splits this in the middle, so they have roughly 120V on either side of neutral, and 240V across both. It is often referred to as “split phase”, but in reality it’s really just a single phase connection with a tap halfway.
In short, North America is 240V single phase country (except industrial stuff… which might be three phase).
The upside is 1) backwards compatibility with older 110V stuff, and 2) because you bond to earth in the middle, the highest voltage in the system is much lower, and therefore safer. To the extent that residual current protection isn’t even required for all sockets (typically just those in “wet” areas).
The downside is you need an extra conductor to the house (neutral and two “hot” ones), so extra material required.
All your high powered appliances will run from the 240V supply. That typically includes the laundry dryer, water heaters, air conditioning, ovens, and so forth. And EV chargers.
American houses, however, tend to have at least a 100A supply. Big houses may have a 200A supply. South African houses typically have a 60A supply, and if you want more, you would typically upgrade to three phase. Our voltages are, for all intents and purposes, the same, and therefore most of the arguments made by Alex in that video basically applies to us as well.