Just curious (not clever enough to work it out) but why are 3 phase
chargers more powerful than single phase fed ones?

Is it just that the mains circuits have different capacities or is a 3
phase when rectified more powerful?

John wrote:

Just curious (not clever enough to work it out) but why are 3 phase
chargers more powerful than single phase fed ones?

Is it just that the mains circuits have different capacities or is a 3
phase when rectified more powerful?

I think it is just because a standard house single phase supply is only
going to provide a maximum of 10kW to a single circuit using standard
components. If one needs a higher power supply it is going to cost a
lot and is routinely supplied as three phase to make the best use of the
available supply cables and standard components.

--

Roger Hayter

On 24/11/2019 11:10, John wrote:

Just curious (not clever enough to work it out) but why are 3 phase
chargers more powerful than single phase fed ones?

Is it just that the mains circuits have different capacities or is a 3
phase when rectified more powerful?

Three phase gives you a number of advantages. A typical domestic supply
is fused at 100A. So at 240V that limits the maximum rate of power
delivery to 24kW. A three phase supply will have three incoming live
phases all fused at 100A, giving total capacity of 72kW.

(there are other advantages to a 3 phase supply - such as having the
capability to power a load between phases rather than just between phase
and neutral, raising the available supply voltage to ~415V. Plus the
ability to do cleaver stuff with motors etc. However most of these will
not have much impact on car chargers)



--
Cheers,

John.

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On Sunday, 24 November 2019 11:10:10 UTC, John wrote:
Just curious (not clever enough to work it out) but why are 3 phase
chargers more powerful than single phase fed ones?

Is it just that the mains circuits have different capacities or is a 3
phase when rectified more powerful?

Bigger electrical loads of all types are three phase to balance up the currents in the electricity supply. unbalanced loads lead to voltages appearing on the neutral and reduced capacity of transformers/switchgear etc.

So if you have a single load of more then approx. 10Kw, the supplier will want you to you having a three phase supply.

John wrote

Just curious (not clever enough to work it out) but why are
3 phase chargers more powerful than single phase fed ones?

For the same reason that 3 phase motors
are more powerful than single phase motors.
The higher current is supplied over 3 phases.

Its actually more complicated than that
with motors, but not with chargers.

Is it just that the mains circuits have different capacities

Yep.

or is a 3 phase when rectified more powerful?

Nope.

On Mon, 25 Nov 2019 05:57:38 +1100, cantankerous trolling geezer Rodent
Speed, the auto-contradicting senile sociopath, blabbered, again:


Just curious (not clever enough to work it out) but why are
3 phase chargers more powerful than single phase fed ones?

For the same reason that 3 phase motors
are more powerful than single phase motors.
The higher current is supplied over 3 phases.

No ****, senile Einstein! BG

--
about senile Rot Speed:
"This is like having a conversation with someone with brain damage."
MID:

On 24/11/2019 11:10:07, John wrote:
Just curious (not clever enough to work it out) but why are 3 phase
chargers more powerful than single phase fed ones?

Is it just that the mains circuits have different capacities or is a 3
phase when rectified more powerful?

There are two aspects.
1) 3 phase has less copper loss than single phase.
2) 3 phase rectification provides significantly less ripple current than
single phase rectification.

Normal domestic and light industrial supplies are 100A feeds which give
a max of 23/24kW depending on supply voltage

Add one more cable and you could have 69/72kW assuming a neutral is not
required.

Yes large machine tools can make this an essential as well, as a friend
discovered a few years ago. although you can simulate three phase its not
going to allow the power needed when the motor starts etc, in the case of
charging a car, this current used to charge it seems very high. Goodness
knows what the cost will be, and one assumes it has its own meter.
Brian

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On Sunday, 24 November 2019 11:10:10 UTC, John wrote:
Just curious (not clever enough to work it out) but why are 3 phase
chargers more powerful than single phase fed ones?

Is it just that the mains circuits have different capacities or is a 3
phase when rectified more powerful?

Bigger electrical loads of all types are three phase to balance up the
currents in the electricity supply. unbalanced loads lead to voltages
appearing on the neutral and reduced capacity of transformers/switchgear
etc.

So if you have a single load of more then approx. 10Kw, the supplier will
want you to you having a three phase supply.