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3 phase or single phase WC supply better?

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Same 3p cable from Meter to 3phase socket for both 1p 40amp HPWC and 3p 32amp HPWC.
Neutral increased in size to be able to handle single phase.
No voltage drop on 24amp 3p, but big voltage drop on 40amp 1p.
I always assumed the voltage drop was due to a large unbalanced draw on 1p (not that I need to charge at this rate :))
The problem sounds like the cable has sufficient gauge for 24 amps, but only just enough gauge for 40 amps.
When running 3 phase, each of the lines takes 24A independently, and when running single phase, two lines are cold and one line is carrying 40A.
The gauge requirement depends on amps and length. If gauge is insufficient the resistance goes up as the line warms, and voltage sags since it's the moveable variable in the V=IR equation.
It's unlikely to be the power supply to the house, because that would be gauged for close to 100 or 200A, given all the different circuits in your house that could be running at once, each on a 10/20/32 amp breaker.
 
No I haven't tried it myself, but others have. But good point, I will grab an M3 and see if it works with mine own eyes
TP grabbed my M3 and tested with Gen 1 UMC 3 phase today. Worked as expected drawing 12KW (67Km/hr) Seems like the way to go for remote cruising in Oz. I considered purchasing but at $690 US for the cheapest setup I could find you would want to be using it a lot to justify.
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So, electrician turned up (a real one, I'm a Desk-Sparky these days ;) )
Long story short, I think he didn't want the hassle of trying to run a new 3C+E cable via some tortuous path in my (2 story) house, so gave an estimate of $2-3k & a wait for cable! WTF ..
Oh, he'd also said he'd have to retrofit the board with some new integral ELCBs breakers because I'd run out of board space since getting solar ....
He said instead he could do the install with my existing 6mm single phase cable for ~$400-$500
... so that what I did :(
$460
Like me, the electrician had to google the American wiring terminology and translate that into appropriate DIP settings to match our local MEN system.

Tom and Joy have a short video on this.

So it didn't turn out too bad, I'm charging at the full 32A single phase and its saying 8kW, slightly better than Toms quoted 7kW, but that probably because my voltage is sitting nicely a bit over 240VAC.

Awesome setup, literally didn't have to do anything to set the charger up, pressed the plug button and the car opened the charger door!
 
I’m or sure how much the installation cost for me yet as I haven’t got the bill :)

I’ve found the wall charger a lot harder to plug in than the mobile charger. It doesn’t sit as flush and I’ve got it wrong a fair few times. Has anyone else experienced something similar?
 
My sparky installed the HPWC yesterday - I have 3 phase power, he installed a new 32A 3-phase breaker in our sub-board, ran a massively thick multi-core cable to the HPWC and flicked the internal rotary switch to 32A.

When I charge, however, the screen in the car and the app show charging at “16A/16A”, around 72 km/hr, and the total power consumption is around 11.5 kW. My solar, PW2 and grid were all injecting juice into Slartibartfast :cool:

Is this all working as expected? I was expecting to see charging at “32A/32A” but maybe I’m missing something... other posts here imply this is what I should be getting.

Merry Tesla Christmas everyone!
 
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My sparky installed the HPWC yesterday - I have 3 phase power, he installed a new 32A 3-phase breaker in our sub-board, ran a massively thick multi-core cable to the HPWC and flicked the internal rotary switch to 32A.

When I charge, however, the screen in the car and the app show charging at “16A/16A”, around 72 km/hr, and the total power consumption is around 11.5 kW. My solar, PW2 and grid were all injecting juice into Slartibartfast :cool:

Is this all working as expected? I was expecting to see charging at “32A/32A” but maybe I’m missing something... other posts here imply this is what I should be getting.

Merry Tesla Christmas everyone!

The AC charger for the M3 maxes out at 11.5kW.
 
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My sparky installed the HPWC yesterday - I have 3 phase power, he installed a new 32A 3-phase breaker in our sub-board, ran a massively thick multi-core cable to the HPWC and flicked the internal rotary switch to 32A.

When I charge, however, the screen in the car and the app show charging at “16A/16A”, around 72 km/hr, and the total power consumption is around 11.5 kW. My solar, PW2 and grid were all injecting juice into Slartibartfast :cool:

Is this all working as expected? I was expecting to see charging at “32A/32A” but maybe I’m missing something... other posts here imply this is what I should be getting.

Merry Tesla Christmas everyone!
That is correct; 16 AMP 3 phase is the max a 3 will use. The only Tesla to date that will use 32 AMP 3 phase is the older S with two on-board chargers.
 
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