On Fri, 3 Feb 2012 12:59:49 -0500, "Arny Krueger"
wrote:

If my tables are right, 2.5 mm is about 10 gauge, which is a lot more
copper than our 12 gauge.

It is called 2.5mm, but it is actually 2.5 square mm, which is about
your 12 gauge.

d

"Mortimer" wrote in message
...
"Arny Krueger" wrote in message
...

"Don Pearce" wrote in message
...

Do the 120V and 240V system share the same high voltage distribution
lines? I mean is the transformation done per house, per street or per
district?

It is done as needed. In a residential neighborhood there may be several
transformers per block. There is a transformer in my back yard and I can
see the next one maybe 6-8 houses (on my side) down.

It just strikes me that with 240V available the requirement
for 120V should be dwindling.

240v has been widely avaiilable here since before WW2.

My expectations are that since power use is likely to decrease, and the
power drain of household equipment of a kind is generally decreasing,
there's no push for more 220 volt usage in homes.

220 volt portable houshold appliances are rare. Just a random thought but
the advent of 90-250 volt wall warts and other stuff with similar
switchmode power supplies are opening the door to future implementation
of more 220 volt house wiring.

The most recent *big* user of 240 volt power was air conditioning, but
almost all of that equipment that is going to exist has probably already
been isntalled, except of course new homes. I don't expect a lot of new
homes to be built for many years.

It really is too low for even distribution within a house.

I would say that its biggest problem is that 12 guage copper wire is
getting to be pretty expensive.

I have experienced lights dimming
significantly when appliances are turned on in many American homes.

Historical artifacts. I just rewired part of my daughter's ca. 1955
house and all I can say is that we added a ton of new circuits and I saw
many strange things that we made go away.

Several hundred dollars worth of 12 gauge Romex and accessories were
involved. Simple things like putting the garbage disposal, microwave,
and toaster oven each on their own circuits make a big difference.

In the UK, all of these could be driven from one ring main without the
need for separate radials from the fusebox for each one.

That makes sense if your rings are 10 gauge (2.5 mm),

There are two cables in parallel since its a ring.

The current is cut in half by the doubled line voltage.

Most houses I've seen just have two ring mains (one for upstairs, one for
downstairs), separate circuits for really high power devices (cooker,
immersion heater, electric shower circuit - if fitted) and one or two
lighting circuits.

My downstairs has something like ten 120 volt circuits, and there are about
another 8 circuits upstairs. As I mentioned, a typical modern US kitchen has
5-6 120 v circuits all by itself, not including the 230 v electric oven.

Electric stoves and ovens are always on their own 230 volt circuit, usually
fused for 30 amps with 10 gauge cable. Don't happen to have one - we cook
and heat with natural gas.


Things like microwaves would be fine in a ring main. Ring mains are fused
at 30 A which means you could have plug-in appliances to a total of 7.2 kW
downstairs and the same upstairs. Mind you, you have to be aware of the
electricity company master fuse which is (I think) around 60 A :-)

The 10 gauge wire, the ring configuration, and the doubled line voltage
explain all that.

I see the ring as being a bit of a problem. I guess you circumvent that
problem by fusing individual power cables on each appliance, if I'm
following your discussion.

On Friday, February 3rd, 2012, at 09:40:03h -0500, Arny Krueger wrote:

I live over a mile from the lake.

Does Lake St Clair normally freeze over?

I would guess that this year it has not.

you can see my house from several angles.

No TV antenna it would appear. Have you never been
tempted to put up a tower?

Do you watch CBET or TV Ontario very often?

I notice that you are at the back of a mini strip mall
on Mack Avenue in which there are two vacancies.

Have these now been filled or have more stores gone under
since the Google car passed by?

Type "grosse kercheval henry" into Google Maps

Presumably you mean the area around Henry Ford Medical Center Pierson Clinic.

It is surprising how many of the newer building look quite similar
to new buildings that one would see in new retails developments in
outer suburbs of some European cities.

"Arny Krueger" wrote in message
...

"Dave Plowman (News)" wrote in message
...
In article ,
Arny Krueger wrote:

Several hundred dollars worth of 12 gauge Romex and accessories were
involved. Simple things like putting the garbage disposal, microwave,
and toaster oven each on their own circuits make a big difference.

Romex is roughly what we call Twin and Earth in the UK?

Googling shows pictures that are nearly identical if not exactly
identical.

What you're saying is radial circuits are commonly overloaded in some
way?

Not commonly, but occasionally in older dwellings. Most of what you are
talking about is due to motor starting surges, so the light dimming is
pretty much cosmetic. Not that I would intentionally tolerate it.

All of those (and more) would work just fine on the one UK circuit.

Given that our toaster ovens use up about 95% of a 15 amp circuit, two of
them put a quick end to 15a fuses and pretty quickly open 15a breakers.
The larger microwaves are only a little lighter on the draw, so a
microwave and a toaster oven on the same circuit won't be very relaible,
either. Ditto for our larger electric coffee and tea pots. I don't know
how to get around that.

Ah, is the limit on a 110V circuit only 15A? I can see how you'd hit that
limit pretty quickly. I'd assumed that with half the voltage the circuits
would be rated for twice the current so as to still be able to drive
equipment of the same power.

I suppose a 3 kW (3-bar) electric fire needs more than a normal circuit,
given that it draws 12.5 A at 240 V, so an equivalent one for 110V would be
a little over 25 A. And as for a 6 kW electric shower, that would be 50 A.
Quite a current! OK, so showers need their own circuit even in 240 V land!

As a matter of interest, when a mains socket is switched from a wall switch
for use with table lamps so they can all be switched on as you come into a
room, are those circuits rated at the same current as other non-switched
circuits or are they specially labelled to prevent people accidentally
plugging powerful appliances into what is effectively a lighting circuit?

"Don Pearce" wrote in message
...
On Fri, 3 Feb 2012 12:59:49 -0500, "Arny Krueger"
wrote:

If my tables are right, 2.5 mm is about 10 gauge, which is a lot more
copper than our 12 gauge.

It is called 2.5mm, but it is actually 2.5 square mm, which is about
your 12 gauge.


Well you still have the doubled advantage of feeding the ring from both ends
and using twice the voltage.

I'm not so sure about rings, but the doubled voltage looks good to me given
that I would have enough appliances that ran on 240 volts to be interesting.
I don't.

"Mortimer" wrote in message
...

Also it doesn't allow high-power devices such as kettles to be driven from
120V, hence the tendency for water in the US to be boiled in a pan on a
cooker hob which much be horrendously slow (I know from when I've had to
do it on a gas or electric hob when the kettle was broken).


I have a 1500 watt electric pot that heats 1.7 L of water in about 3
minutes. Less water, down to about a liter (what it takes to cover the
coils) heats significantly quicker.

Works for me!

"Don Pearce" wrote in message
...
On Fri, 3 Feb 2012 09:40:03 -0500, "Arny Krueger"
wrote:

Type "1600 prestwick grosse" into Google Maps and you can see my house
from
several angles. Step a bit east of the default location for the best
possible view looking about north.

So many cables on those poles. What on earth are they all?

That really isn't pretty.

Agreed.

On the pole:

Two cable system local feeds plus the main lines for about a dozen streets.
Yup, two completely independent digital TVcable/internet/phone systems -
isn't competition lovely?

Analog Telephone lines for my house plus the 8 or so businesses

Large analog telephone cable for a goodly number of streets.

Electric 120/240 for my house plus the businesses.

The top 3 wires are 4800 volts 3 phase to keep the power transformers in our
back yards happy.

The pole also holds the battery box for one of the 2 cable systems. The
other one is in my back yard.

Since the picture was taken, the battery box was about doubled in size and
the wiring was cleaned up.

In a newer suburbs it would all be buried.

"J G Miller" wrote in message
...
On Friday, February 3rd, 2012, at 09:40:03h -0500, Arny Krueger wrote:

I live over a mile from the lake.

Does Lake St Clair normally freeze over?

Yes, but not so much lately.

I would guess that this year it has not.

Correct.

you can see my house from several angles.

No TV antenna it would appear. Have you never been
tempted to put up a tower?

There used to be one, but we've had cable for decades.

Do you watch CBET or TV Ontario very often?

No, but I watch the BBC USA channel on cable.

I notice that you are at the back of a mini strip mall
on Mack Avenue in which there are two vacancies.

Mack Avenue is solid businesses on the west side from Moross to Vernier, and
intermittant businesses on the east side.

Have these now been filled or have more stores gone under
since the Google car passed by?

I think we have 2 current vacancies. At least 3 new businesses have moved in
over the past year, and two that were active when the picture was taken have
folded or moved.

There is a major problem with parking. We walk or ride our bikes a lot, but
almost nobody else does.

Type "grosse kercheval henry" into Google Maps

Presumably you mean the area around Henry Ford Medical Center Pierson
Clinic.

Yes. We call that area "Villiage on the Hill".

BTW the building accorss the street at 120-130 Kercheval is owned by a
friend and was built about 5 years ago.

It is surprising how many of the newer building look quite similar
to new buildings that one would see in new retails developments in
outer suburbs of some European cities.

Completely intentional. Strongly encouraged by the town councils.

Many of the residences around here are also in a style we call "Colonial".
They sort of go with the stores.

BTW my son lives in eastern Pennsylvania so I know what *real* colonial
looks like and this isn't it. ;-)

"Dave Plowman (News)" wrote in message
...
In article ,
Arny Krueger wrote:
We did not have the "cleansing" effects of a world war fought in our
country to push us along. Also, electrical distribution had a very rapid
and early introduction so we have a ton of very old work that is still
in use.

It's not binding on the rest of the world but the town I lived in in
Germany looked like it had been reworked from top to bottom *after*
WW2. We had 416 3 phase in our apartment for heating water.

AFAIK the nearest three phase distribution point here to my house here
in Grosse Pointe is about a half mile away. Our church here in town has
a number of 3 phase motors and it has its own 3 phase line and separate
pole transformer for just that phase.

I've never quite understood why so many US towns seem to have overhead
wiring for mains. It's very unsightly.

When these places were wired (1910-1935), underground wiring was
prohibitively expensive. Underground became the rule in the 70's.

"Mike Tomlinson" wrote in message
...
In article , Dave Plowman (News)
writes

I've never quite understood why so many US towns seem to have overhead
wiring for mains. It's very unsightly.

The pole transformers aren't pretty either, though produce quite
spectacular pyrotechnics when they fail, which seems to happen more
often than it should.

I'm on my second one, but the first went quietly.

One went off like the 4th of July a few streets over, maybe 10 years ago.