On Sun, 30 Jun 2019 00:48:36 +0300, upsidedown@downunder.com wrote:
On Thu, 27 Jun 2019 22:12:01 -0700, John Larkin
jjlarkin@highlandtechnology.com> wrote:
On Fri, 28 Jun 2019 07:05:14 +0300, upsidedown@downunder.com wrote:
On Thu, 27 Jun 2019 18:04:02 -0700, John Larkin
jjlarkin@highland_snip_technology.com> wrote:
On Thu, 27 Jun 2019 16:17:35 -0700 (PDT), Lasse Langwadt Christensen
langwadt@fonz.dk> wrote:
fredag den 28. juni 2019 kl. 01.12.45 UTC+2 skrev John Larkin:
On Thu, 27 Jun 2019 17:31:20 +0300, upsidedown@downunder.com wrote:
On Thu, 27 Jun 2019 07:55:53 +0100, Tom Gardner
spamjunk@blueyonder.co.uk> wrote:
On 27/06/19 07:20, upsidedown@downunder.com wrote:
On Wed, 26 Jun 2019 23:42:43 -0400, bitrex <user@example.net> wrote:
On 6/26/19 10:09 PM, Rick C wrote:
On Wednesday, June 26, 2019 at 9:57:47 PM UTC-4, keith wright wrote:
On Wednesday, 26 June 2019 18:14:57 UTC-7, bitrex wrote:
...
"Charging at home will require
the installation of a dedicated high-capacity outlet"
a 40 amp level 2 charger unit is plenty for many use cases and
installing one is not a complex job. it won't charge up the car in a
couple hours. it'll charge a 3 up ~150 miles overnight, how many people
are driving 150 miles a day every day goddamn.
The summary seems to make it out like you can either charge from a 120
volt outlet over 1.5 days or you have to install a three phase AC-DC
level 3 charger with a cable 4" in diameter to charge the car.
...
'Which' is a UK magazine so a normal wall socket can do up to 2-3kW (as a reference other cars in the UK seem to be set to 10A resulting in 2.4kW).
I did forget that this was a UK magazine. I have talked about this with folks from there and I never got a clear answer, but it seems like they do 13 amp outlets easily, but to get more they wire 3 phase, which *is* a lot more hassle... at least I guess so. They talk about totally different wiring methods than we use and smaller service to the house, so maybe higher current 240 volt outlets aren't so easy. On the other hand, they tend to drive shorter distances so the daily need for charging is not as much. The 3 kW available from a standard outlet gets you around 180 miles on a model 3... assuming they don't do the derating thing that we do in the US. Can someone confirm that?
In the UK there are a number of smaller EVs available with smaller batteries and higher mileage. I don't know the names, but they seem to work well according to the owners.
I believe it's common in the UK and Europe to have smaller per-dwelling
or per apartment (flat?) structure distribution transformer/pole pig as
compared to the US where there's usually one large pole pig to supply a
neighborhood
It is the other way around. In Europe pole mounted transformers are
typically 100-315 kVA feeding dozens of detached houses up to several
hundred meters from the distribution transformer.
Here you /never/ see pole mounted transformers for
domestic properties.
So you have those low transformer buildings every few hundred meters
feeding the houses around it.
In Finland, you can get at least a 3x63 A 230/400 V up to 600 m from
the (ground or pole mounted) distribution transformer from most
electric companies.
In the US, due to lower voltage and hence large currents, a
distribution "pig" transformer only serves one or at most a few
houses.
That's silly. The size of a transfomer depends on KVAs, not voltage.
My house is 120-0-120. In other words, it is fed 240 volts.
and here we get 3*240V using only one extra wire
Residential three phase?
I even have three phases in my top floor city apartment, although it
currently just feeds the electric stove. In my country house, the
electric sauna, electric stove and a small water pump is all three
phase.
Are any of those loads actually 3-phase devices, or are they just
three single-phase loads? Controlling true three power takes more
switches or triacs than single phase, and there is no benefit for
resistive or small motor loads.
The largest single phase motors I have seen here are less than 2 kW,
everything larger are three phase. A typical example would be the heat
pump.
The nice features of 3p motors is that no starter capacitor is needed,
you can change the rotation direction by swapping two phases, you can
easily make a wye/delta soft starter etc.
Large resistive heaters are 3p, such as sauna or indirect electric
heaters. If the resistive elements are connected in wye, you could in
principle feed them with a single phase paralleling the hot ends of
the elements, but the neutral current may be too large. If the
resistive elements are connected in delta, paralleling the phase wires
doesn't obviously work. Connecting one phase wire to neutral, a
greatly reduced power would be available.
Are there 3-phase outlets?
There are often a single 3x16 A three phase socket close to the
distribution panel, thus in practice you would need a long 3p
extension cords for ad hoc 3p loads. Such might be used especially
during the of the house to run some high power tools or temporary
heaters.
I do not know if it is even legal today, but a few decades ago some
welding transformers had taps for 220 V and 380 V. If only 220 V 10 A
was available, the 220 V tap was used and you could nominally load
with 2.2 kW. However if 3x10 A 220/380 V was available, connect the
primary 380 V tap between two phase wires from a three phase feed,
thus nominally 3.8 kW would be available.
These days a 6 pulse rectifier fed from a 3p supply would be used and
then a DC/DC converter at a higher frequency to generate the actual
(DC) welding arc. Older welders complained that the new welding
transformer was too light like a toy and did not remain in place when
moving the thick welding cables. Extra weight was added to some models
so that they looked more professional.
I can't imagine that an electric stove has 3-phase heater elements.
Each element is single phase in domestic stoves.
One problem with ABCN (wye) 3-phase systems is neutral current. It is
zero in a well balanced system and no more than any leg current in a
badly balanced one... for sine wave loads. Nonlinear loads, particular
rectifiers followed by filter caps, can overload the neutral, because
the timing of the peak currents prevents cancellation.