Electrical code Compliance - Re: US system is not as inefficient as I once thought

Author

Re: US system is not as inefficient as I once thought

Tim Gard

2007-02-25, 5:25 pm

However an insulation sufficient to block 5000 volts would be substancial.
And God help you if your dog chews through a lamp cord.

Tim

>If a 5,000 volt service was
> supplying your house with electricity, the electrical wire that enters
> your
> house wouldn't be much bigger than your telephone wire.
>
> Robert
>
>

phil-news-nospam@ipal.net

2007-03-01, 5:25 pm

In alt.engineering.electrical Tim Gard <dragmit@adelphia.net> wrote:

| However an insulation sufficient to block 5000 volts would be substancial.
| And God help you if your dog chews through a lamp cord.

You'd definitely need help scraping the mess off the walls :-)

There are definitely some cases where lower voltage is better. Consider
a light bulb suitable for ever higher voltages. A 100 watt filament for
5000v would be thinner and/or longer than a 4 watt filament for 120v.

I do think a higher voltage is more suited to larger appliances in a home.
Incandescent lighting and some smaller devices would be better at a lower
voltage. I have posted before about the system design I would have made if
I had the opportunity to do so without legacy economic impact (e.g. if I
could go back via a time machine and make the early system design decision).
The system I would have would be a dual-voltage system in the home. Larger
loads would always be connected line-to-line at 288 volts. That would be
144 volts relative to ground on single phase supplies, or 166 volts relative
to ground on three phase supplies. This might even be made higher such as
360 volts (180 or 208 volts to ground). The lower voltage would always be
single phase with 12 volts relative to ground (but might be set up as dual
phased with 12-0-12 for 24 volts line-to-line). This would primarily be
used for incandescent lights up to 60 watts, electric shavers, small tools,
and small appliance wall-warts. Larger appliances would use the 288 volt
system. The service drop would be 288 volts, and the 12 or 12/24 system
would be derived from it.

So with the above system, would you find 288 volts, or maybe even 360 volts,
acceptable?

--
|---------------------------------------/----------------------------------|
| Phil Howard KA9WGN (ka9wgn.ham.org) / Do not send to the address below |
| first name lower case at ipal.net / spamtrap-2007-03-01-1520@ipal.net |
|------------------------------------/-------------------------------------|

Tim Gard

2007-03-06, 9:25 am

Yes, I agree Phil. I was trying ti imagine an entire residential system at
elevated voltages. And boy, I could sure put good use to that time machine
if you ever find it! Make wine today, push a button and instant aged!
drink it, then go back. Wat-a-plan!

Tim Gard

<phil-news-nospam@ipal.net> wrote in message
news:es7gv20283a@news1.newsguy.com...
> In alt.engineering.electrical Tim Gard <dragmit@adelphia.net> wrote:
>
> | However an insulation sufficient to block 5000 volts would be
> substancial.
> | And God help you if your dog chews through a lamp cord.
>
> You'd definitely need help scraping the mess off the walls :-)
>
> There are definitely some cases where lower voltage is better. Consider
> a light bulb suitable for ever higher voltages. A 100 watt filament for
> 5000v would be thinner and/or longer than a 4 watt filament for 120v.
>
> I do think a higher voltage is more suited to larger appliances in a home.
> Incandescent lighting and some smaller devices would be better at a lower
> voltage. I have posted before about the system design I would have made
> if
> I had the opportunity to do so without legacy economic impact (e.g. if I
> could go back via a time machine and make the early system design
> decision).
> The system I would have would be a dual-voltage system in the home.
> Larger
> loads would always be connected line-to-line at 288 volts. That would be
> 144 volts relative to ground on single phase supplies, or 166 volts
> relative
> to ground on three phase supplies. This might even be made higher such as
> 360 volts (180 or 208 volts to ground). The lower voltage would always be
> single phase with 12 volts relative to ground (but might be set up as dual
> phased with 12-0-12 for 24 volts line-to-line). This would primarily be
> used for incandescent lights up to 60 watts, electric shavers, small
> tools,
> and small appliance wall-warts. Larger appliances would use the 288 volt
> system. The service drop would be 288 volts, and the 12 or 12/24 system
> would be derived from it.
>
> So with the above system, would you find 288 volts, or maybe even 360
> volts,
> acceptable?
>
> --
> |---------------------------------------/----------------------------------|
> | Phil Howard KA9WGN (ka9wgn.ham.org) / Do not send to the address below
> |
> | first name lower case at ipal.net / spamtrap-2007-03-01-1520@ipal.net
> |
> |------------------------------------/-------------------------------------|

John Gilmer

2007-03-11, 9:25 pm

> Yes, I agree Phil. I was trying ti imagine an entire residential system
at
> elevated voltages. And boy, I could sure put good use to that time
machine
> if you ever find it! Make wine today, push a button and instant aged!
> drink it, then go back. Wat-a-plan!

Unless you have a super energy hog of a home (e.g.: resistance heating or
electrically powered demand water heater) a 200 amp service is "Plenty".
The reality is that most familys would not see any difference to their life
styles had they only a 100 amp service.

I definitely would like to see more 240 volt appliances to include dish
washing machines and "super" microwave ovens. But 120/240 is "pretty
good."

>
> Tim Gard
>
> <phil-news-nospam@ipal.net> wrote in message
> news:es7gv20283a@news1.newsguy.com...
home.[color=darkred]
lower[color=darkred]
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be[color=darkred]
dual[color=darkred]
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|---------------------------------------/----------------------------------|[color=darkred]
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spamtrap-2007-03-01-1520@ipal.net[color=darkred]
|------------------------------------/-------------------------------------|[color=darkred]
>
>

phil-news-nospam@ipal.net

2007-03-12, 1:25 pm

In alt.engineering.electrical John Gilmer <gilmer@crosslink.net> wrote:

| Unless you have a super energy hog of a home (e.g.: resistance heating or
| electrically powered demand water heater) a 200 amp service is "Plenty".
| The reality is that most familys would not see any difference to their life
| styles had they only a 100 amp service.
|
| I definitely would like to see more 240 volt appliances to include dish
| washing machines and "super" microwave ovens. But 120/240 is "pretty
| good."

I have seen microwave ovens that use 240 volt. But they were big ones,
probably with a lot of power. I'd like to see more appliances available
in 240 volt (6-15P or more as the case may need to be) versions. One
thing that will need to be changed for that is removal of NEC 210.6(A)(2).

My big beef is against anything that needs a 3-wire supply (dual voltage).
But, I do read from computer power supply specs that most of them are more
efficient on a 220-240 volt power source (though not enough so to justify
using a step-up transformer to get it).

--
|---------------------------------------/----------------------------------|
| Phil Howard KA9WGN (ka9wgn.ham.org) / Do not send to the address below |
| first name lower case at ipal.net / spamtrap-2007-03-12-1050@ipal.net |
|------------------------------------/-------------------------------------|

John Gilmer

2007-03-12, 8:25 pm

>
> I have seen microwave ovens that use 240 volt. But they were big ones,
> probably with a lot of power. I'd like to see more appliances available
> in 240 volt (6-15P or more as the case may need to be) versions. One
> thing that will need to be changed for that is removal of NEC 210.6(A)(2).

What, pray, does it say?

>
> My big beef is against anything that needs a 3-wire supply (dual voltage).

Exactly.

"Standard" US electric clothes dryers have 240 heaters but 120 volt motors
and timers/electronics. Electric stoves have 240 heaters but 120 volt
timers/electronics. That might have something to do with the fact that in
a significant part of the market (condos, in particular) you don't get 240
volts but only 208. Running a 240 volt motor on 208 is asking for trouble.
Running a 240 heater at 208 doesn't make much difference and in any case it
isn't a "big deal" to substitute a 208 volt heater.

phil-news-nospam@ipal.net

2007-03-14, 5:25 pm

In alt.engineering.electrical John Gilmer <gilmer@crosslink.net> wrote:
|
|
|>
|> I have seen microwave ovens that use 240 volt. But they were big ones,
|> probably with a lot of power. I'd like to see more appliances available
|> in 240 volt (6-15P or more as the case may need to be) versions. One
|> thing that will need to be changed for that is removal of NEC 210.6(A)(2).
|
| What, pray, does it say?

You couldn't look it up?

Basically it says that circuits cannot be wired to supply voltage in
excess of 120 volts between conductors for loads less than 1440 VA.
That means for smaller appliances, we're stuck with 120V only, unless
we try to get clever and insist that our 2000W 240V 6-15P welder is
portable enough to use in every room of the house :-)

|> My big beef is against anything that needs a 3-wire supply (dual voltage).
|
| Exactly.
|
| "Standard" US electric clothes dryers have 240 heaters but 120 volt motors
| and timers/electronics. Electric stoves have 240 heaters but 120 volt
| timers/electronics. That might have something to do with the fact that in
| a significant part of the market (condos, in particular) you don't get 240
| volts but only 208. Running a 240 volt motor on 208 is asking for trouble.
| Running a 240 heater at 208 doesn't make much difference and in any case it
| isn't a "big deal" to substitute a 208 volt heater.

OTOH, if all of the load is well balanced over the 2 line conductors, that
should be more efficient even for the same load.

Europe has proof that the electronics can run on 240 volts. So can motors
(but 208 volt versions would be needed). So can light bulbs safely if they
are of the bi-pin type (though at the small wattages, a low voltage from a
tiny transformer might be better).

A true two-wire applicance could still be shipped with a 14-XXP cord, but
you could substitute a 6-XXP for it (I would).

Ever seen a 14-15R receptacle. Try plugging a 6-15P into it. It fits!

--
|---------------------------------------/----------------------------------|
| Phil Howard KA9WGN (ka9wgn.ham.org) / Do not send to the address below |
| first name lower case at ipal.net / spamtrap-2007-03-14-1500@ipal.net |
|------------------------------------/-------------------------------------|

Lionel

2007-03-16, 3:25 am

On 14 Mar 2007 20:10:34 GMT, phil-news-nospam@ipal.net wrote:

>Europe has proof that the electronics can run on 240 volts. So can motors
>(but 208 volt versions would be needed). So can light bulbs safely if they
>are of the bi-pin type (though at the small wattages, a low voltage from a
>tiny transformer might be better).

Australia has been 240VAC only for domestic use since before I was
born. I'm really glad we don't have to screw around with multiple
voltages in homes.

--
W "Some people are alive only because it is illegal to kill them."
. | ,. w ,
\|/ \|/ Perna condita delenda est
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