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Why only 16A of 32A?

Mtljckt

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I upgraded my electrical cables and I'm now able to use three phases charging. Also applied for 30kw 64A for the main break. The improvement is big but the charger still says only 16A out 32A available. Is this because of the car's limited ability (didn't purchase the upgraded AC charger)?
16x230x3=11kw?

Porsche Taycan Why only 16A of 32A? 20211112_172326
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Jhenson29

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If you didn’t option the larger AC charger, then the car would be limited to 11kW.

And 3-phase power is times the square root of 3 (1.73).

Are you sure the voltage isn’t 400VAC?
 

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If you didn’t option the larger AC charger, then the car would be limited to 11kW.

And 3-phase power is times the square root of 3 (1.73).

Are you sure the voltage isn’t 400VAC?

230 volt in Europe is between phase and zero. 400 volt is between phases.

so 230x3x16 is correct is 11 kW

or 400x square root of 3 x 16 is also 11 kW.
 
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Mtljckt

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Yes, it makes sense, but why isn't the charger showing 16x3=48A, since it gets all three phases? Current reading is the same as for a single phase (though charging is correct).
 

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Yes, it makes sense, but why isn't the charger showing 16x3=48A, since it gets all three phases? Current reading is the same as for a single phase (though charging is correct).
Any electrician should answer this correctly, but I am guessing the norm is to state the amps per phase. Main circuit breakers are rated as say 63 amp even if they provide 3 phase.
 


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Mtljckt

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Any electrician should answer this correctly, but I am guessing the norm is to state the amps per phase. Main circuit breakers are rated as say 63 amp even if they provide 3 phase.
Sure, but they are three... and I thibk there is no difference on the charger's screen beteween one phase and three phase, both equiped with same breakers.
 

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The display is showing that it's charging at 16A of the maximum of 32A.
So guess you are charging at 230V x 16A x 3P = 11 kW
If you were charging at 230V x 32A x 3P = 22kW

Guess you can also charge at mono-phase, then it would be
230V x 16A x 1P = 3,6kW
or
230V x 32A x 1P = 7,2 kW
 

Jhenson29

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230 volt in Europe is between phase and zero. 400 volt is between phases.

so 230x3x16 is correct is 11 kW

or 400x square root of 3 x 16 is also 11 kW.
I see; it's a wye. But it's not really either/or as equivalents. It's using one or the other (i.e. not interchangeably). It depends on how it's connected at the car, but I find it very unlikely that it's not pulling line-line voltage and using the 400VAC. Is the neutral connected at the car end? May have to see internals of rectifier also, but it seems like they would just take all 3 phases to the same rectifier since all they would have to do is add two diodes relative to a two conductor system.

Apologies in advance if there's some aspect of the 3-phase charging I'm not aware of since we don't have that in the US and I'm not 100% sure how it gets connected at the car. I am making the assumption that all three phases go to the car because I can't imagine how else it would work, but please correct me where I'm wrong.

Yes, it makes sense, but why isn't the charger showing 16x3=48A, since it gets all three phases? Current reading is the same as for a single phase (though charging is correct).
Any electrician should answer this correctly, but I am guessing the norm is to state the amps per phase.
Current is shown per conductor because that's what is cared about with current; current on individual conductors. And because it's a balanced load (all three phases are the same) it only has to show one. If it were an unbalanced load, then it would need to show them all, but separately (not summed). There's no interest in the sum of the current on a 3-phase system.

My EVSE at home is a two conductor 240VAC system and it only shows one current, even though the current is present in both wires. No different for 3-phase.

Note that the current isn't just all going out to the car. There's as just as much coming back as there is going out (or else you've got a problem!). And actually, with AC, its barely "moving" at all....more like jiggling back and forth.

The 3-phase needs a return path just like the two-wire system. Each phase spends some time as the return for the others. Hence why power is not just "current * 3".
 


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In Belgium we have 3P + N
You get 230V between each phase and neutral and 400 between phases.
 

Jhenson29

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In Belgium we have 3P + N
You get 230V between each phase and neutral and 400 between phases.
But is the neutral connected to/used by the actual car?

Here we have 240VAC line to line and 120VAC line to neutral. My PMC+ plugs into a 14-50 with two lines, a neutral, and a ground. But the neutral stops there. It doesn’t go to the car (it doesn’t even actually go to the EVSE, but the car is the relevant part). So, I don’t have 120VAC x 40 amps x 2. I have 240VAC x 40 amps x 1.
 

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230 volt in Europe is between phase and zero. 400 volt is between phases.

so 230x3x16 is correct is 11 kW

or 400x square root of 3 x 16 is also 11 kW.
I don‘t know for France…but in Slovenia, your math doesn’t work.
if you charge at 230V (single phase), for home usage, you can normaly get up to 32Ampers, but most of us are having 25Amps only. So 230 * 32 = 7.36 kw per hour only.
with 3-phases (400V) ah home, I‘m charging at 16Amps (400*16* 1,73= 11 kwh)…. While I have 32Amps in the garage at work (=22kw per hour)….
also, on charging device, i can select any Amp as I want…6, 10, 16, 32…
 

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I don‘t know for France…but in Slovenia, your math doesn’t work.
if you charge at 230V (single phase), for home usage, you can normaly get up to 32Ampers, but most of us are having 25Amps only. So 230 * 32 = 7.36 kw per hour only.
with 3-phases (400V) ah home, I‘m charging at 16Amps (400*16* 1,73= 11 kwh)…. While I have 32Amps in the garage at work (=22kw per hour)….
also, on charging device, i can select any Amp as I want…6, 10, 16, 32…
I believe we are saying exactly the same thing!
 

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I believe we are saying exactly the same thing!
You said 230*3*16… and I dont know how you can get 11kw @230V with 16Amps only?
afaik, such combo gives you 3.68kw per hour only.
 

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You said 230*3*16… and I dont know how you can get 11kw @230V with 16Amps only?
afaik, such combo gives you 3.68kw per hour only.
Yes ech phase will provide 3.68 kW, but you have three phases.

230 volts times 3 phases times 16 amps will give you 11 kW!.
 

B61

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Didn’t know that such combo is possible.
imthought that 3phases are for 400V only.
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