Need some help, what is percentage US voltages on 115V, 208V

[Whoey Louie]

On Friday, November 1, 2019 at 5:32:14 AM UTC-4, Piotr Wyderski wrote:

Rick C wrote:

What is stupid about that? It is to protect the line coming into the home.

Stupid is that they are rated WAY below the capacity of the line and
their value reflects the maximal allocated power budget, as per ones
contract. E.g. a typical older flat has 20A fuse, because the contract
specifies 4.5kW power budget. You can get at most 32A on a single phase
and on this very same line -- this is entirely a contractual update. If
you need more, you need to upgrade to a three-phase system. Then you get
3x20A.

The building lines are protected separately.

In case of houses the limits are higher, usually 3x63A, but I have never
heard of 200A. This rating is typical for buildings.

We do the same here.

No, you protect the lines, not throttle the consumption level. This is OK.

A main breaker obviously does both. You can't exceed the limit of
the fuse, that certainly "throttles" the total capacity of the service.
It also only protects the wires against an overload past the breaker.
It doesn't protect the wires between the transformer and breaker.
If something comes in contact with them, the breaker does nothing.
Which is different than a breaker protecting branch circuits, where
the breaker protects the wiring from the breaker to the loads.

Yes, we save on lighting expenses that way. ;-)

But come on, you claimed 90A wiring capability elsewhere in the thread.
Do you use busbars for that? 90A is 8W waste power per milliohm -- creepy.

No, we use wire. Not unusual to see 100A subpanels, for example,
wired to the main panel. And that's just the peak capacity.
Actual usage is something totally different. The bill here is
typical ~600kwh for a month. That works out to about 7a continuous.
The wire losses depend on the current. If we take an average wire
run of 50 ft, use 14g which is the smallest branch circuit gauge
allowed, you have a whopping .25 ohms resistance. Using a 7a
current, that works out to 12 watts lost, 840 watts delivered
to the load. That's a loss of just 1.4%. If we doubled the
voltage, the loss would be 0.7%, not what I'd call significant.
My bill for that monthly power is about $75. So, I'd save 52 cents
a month. Doesn't get me too excited....



If we were to start from scratch, I see
compelling advantages to going with 240V as the standard for all
loads, eg an electric kettle could heat twice as fast. I see
some small advantages, eg the 50 cents above, but I sure
don't see a compelling advantage to 3 phase for homes.

You still haven't explained any reason why you would need three phase power in the home.

Nothing needs to be explained, because this is whay you are given
without asking. You don't need to explain the need for a water pipe as well.

In other words, you have no explanation.

What do you need with three phase in the home that you can't supply with 240 volts?

The kitchen equipment can use enormous amount of power. Waer heaters
even more.

The only kitchen equipment in a house that I'm aware of that needs a
lot of power are cooktops and ovens and I wouldn't call those
"enormous". We run those off 240V single phase just fine. Typically
a 30A or 40A circuit. Which also works fine for AC equipment,
heat pumps, etc.

 

[Rick C]

On Friday, November 1, 2019 at 11:06:29 AM UTC-4, Whoey Louie wrote:

If we were to start from scratch, I see
compelling advantages to going with 240V as the standard for all
loads, eg an electric kettle could heat twice as fast. I see
some small advantages, eg the 50 cents above, but I sure
don't see a compelling advantage to 3 phase for homes.

Your assumption that a kettle would boil twice as fast is based on an assumption that the same size wire and so the same current capacity would be used. I believe in the UK circuits can be typically 9 or 13 amps, so smaller than the 15 or 20 we typically use.

If we weren't going to save on the cost of wiring there is no real reason to convert. Boiling water for tea faster is not a very compelling reason to worry with even thinking about which way to go. I suppose hotter room heaters is another potential advantage, but they are already pretty dangerous now.

--

Rick C.

++-- Get 1,000 miles of free Supercharging
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[Lasse Langwadt Christense]

fredag den 1. november 2019 kl. 14.44.24 UTC+1 skrev Michael Terrell:

On Thursday, October 31, 2019 at 4:05:29 PM UTC-4, upsid...@downunder.com wrote:
On Thu, 31 Oct 2019 21:00:43 +0100, Gerhard Hoffmann <dk4xp@arcor.de
wrote:


When we were students, we also had a ham radio linear amplifier
that ran on 3 phase. 2 QB5/1750 tubes, 5.5KV @ 1A+.
That was not exactly legal, but fun. Statute-barred a long time.

At those voltages it is hard to get any big storage capacitors, so
using a 6 pulse, three phase rectifier and the anode voltage is smooth
enough (4 % ripple).

4% would have a noticeable hum and never meet FCC standards. HV capacitors were available for big transmitters. They were large, oil filled with ceramic insulators. Some weighed several hundred pounds, but were still in daily service over 50 years later. Phase correction capacitors used in power distribution were similar but usually lower capacitance.

you can get from three phases to six phases with just transformers, I think a 12 pulse 6-phase rectifier is ~1% ripple

 

[Rick C]

On Friday, November 1, 2019 at 5:32:14 AM UTC-4, Piotr Wyderski wrote:

Rick C wrote:

What is stupid about that? It is to protect the line coming into the home.

Stupid is that they are rated WAY below the capacity of the line and
their value reflects the maximal allocated power budget, as per ones
contract. E.g. a typical older flat has 20A fuse, because the contract
specifies 4.5kW power budget. You can get at most 32A on a single phase
and on this very same line -- this is entirely a contractual update. If
you need more, you need to upgrade to a three-phase system. Then you get
3x20A.

I don't know what to tell you pal. The utility has to provide distribution and someone provides generation, all of which need to be budgeted for. If your usage is on the charts as 4.5 kW and you start drawing 9 or 13 kW at the same time as everyone else, I expect that would cause problems. Having a limiter in the line makes perfect sense to me.

The building lines are protected separately.

In case of houses the limits are higher, usually 3x63A, but I have never
heard of 200A. This rating is typical for buildings.

We do the same here.

No, you protect the lines, not throttle the consumption level. This is OK..

I don't know how the utility deals with extreme peak loads here. In some areas they just cut power off to sections. Which do you prefer, getting your apportioned amount of power or getting what you ask for most of the time but none a other times?

Yes, we save on lighting expenses that way. ;-)

But come on, you claimed 90A wiring capability elsewhere in the thread.
Do you use busbars for that? 90A is 8W waste power per milliohm -- creepy..

I don't know what you are talking about or where you are going with this. A 90 amp circuit would provide 72 amps to charge my car and would require 3 gauge wire. That's about 24 kW. My wire run would be around 30 feet not counting the 20 foot flexible cable to the car.

I have no idea why you have an issue with this. Such a set up is common with Tesla owners who elect to install a HPWC... if they don't install a 100 amp breaker and put two HPWCs on the same line. This is legit because the two units talk and can share the power without going over 80 amps on the circuit.

You still haven't explained any reason why you would need three phase power in the home.

Nothing needs to be explained, because this is whay you are given
without asking. You don't need to explain the need for a water pipe as well.

That's easy to explain. Water is required for humans to habitate. A given size pipe coming into a home I can't justify, but I'm sure others can.

I'm thinking the only reason for bringing three phase power into a home it if it saves some cost in the transformer or elsewhere. I've never heard of that.

What do you need with three phase in the home that you can't supply with 240 volts?

The kitchen equipment can use enormous amount of power. Waer heaters
even more.

"Enormous" is a subjective term. We manage just fine on 240 volts here in the US. If it is typical that homes need instant on hot water for showers, fine. I've just not heard anyone say that. Certainly there is nothing in the kitchen that can't be supplied by 240 volts.

You have a welding machine in your home?

I don't, but many of my friends do. I am considering buying one.

Lol

--

Rick C.

+-+- Get 1,000 miles of free Supercharging
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[Rick C]

On Friday, November 1, 2019 at 10:06:32 AM UTC-4, Michael Terrell wrote:

On Thursday, October 31, 2019 at 7:35:32 PM UTC-4, John Larkin wrote:

There are roughly 15 different outlet types in use in the USA. Maybe
more! Some are 240 with neutral and ground, some are 240 with ground
but no neutral. I think there is a 120-240 outlet all in one somehow.
It's the Wild West.

The 120-240 outlets are common in some commercial buildings. They are for the custodial service to power floor buffers of either type. I saw a lot of them in schools, in hallways and large rooms when I serviced industrial electronics.

Leviton and Hubbel both sell a wide variety of residential, commercial and industrial power connectors.

I worked in a shop that was in a room off a parking level in an apartment building. The 120 volt outlets were wired with one phase of the 240 on one socket and the other phase on the other socket in the standard two socket outlet box. So you could measure 240 volts between the two. I assume this saved on wire costs and also helped to spread the loads between the two phases.

--

Rick C.

+-++ Get 1,000 miles of free Supercharging
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On Fri, 1 Nov 2019 07:48:22 -0700 (PDT), Lasse Langwadt Christensen
<langwadt@fonz.dk> wrote:

fredag den 1. november 2019 kl. 14.44.24 UTC+1 skrev Michael Terrell:
On Thursday, October 31, 2019 at 4:05:29 PM UTC-4, upsid...@downunder.com wrote:
On Thu, 31 Oct 2019 21:00:43 +0100, Gerhard Hoffmann <dk4xp@arcor.de
wrote:


When we were students, we also had a ham radio linear amplifier
that ran on 3 phase. 2 QB5/1750 tubes, 5.5KV @ 1A+.
That was not exactly legal, but fun. Statute-barred a long time.

At those voltages it is hard to get any big storage capacitors, so
using a 6 pulse, three phase rectifier and the anode voltage is smooth
enough (4 % ripple).

4% would have a noticeable hum and never meet FCC standards. HV capacitors were available for big transmitters. They were large, oil filled with ceramic insulators. Some weighed several hundred pounds, but were still in daily service over 50 years later. Phase correction capacitors used in power distribution were similar but usually lower capacitance.


you can get from three phases to six phases with just transformers, I think a 12 pulse 6-phase rectifier is ~1% ripple

You need two transformers or just two sets of secondaries, one set
connected in delta feeding a 6 pulse rectifier and the other set of
secondaries connected in wye feeding a separate 6 pulse rectifier. The
DC supplies are then connected in series. Thanks to the phase shift
between delta and wye, the combined DC ripple is greatly reduced in
this 12 pulse configuration.

Using zigzag transformer secondaries, it is easy to make 18 pulse
rectifiers.

The nasty thing about a simple 6 pulse rectifier is not so much the
ripple but the low power factor, drawing large peak currents. For this
reason, some form of power factor correction (PFC) may be needed.

However, if you have to use iron core step-up or step-down
transformers, you could easily use a 12 or 18 pulse rectifier, which
reduces ripple even further but most importantly increases the power
factor, thus nearly sinusoidal current is drawn from the mains.

 

[keith wright]

On Friday, 1 November 2019 08:32:00 UTC-7, Rick C wrote:
....

Your assumption that a kettle would boil twice as fast is based on an assumption that the same size wire and so the same current capacity would be used. I believe in the UK circuits can be typically 9 or 13 amps, so smaller than the 15 or 20 we typically use.
....

Strictly speaking the circuits are usually 30Amp (wired as a ring main) with a local fuse inside the plug that depends upon the load. It can be up to 13A.

kw

 

[Whoey Louie]

On Friday, November 1, 2019 at 11:32:00 AM UTC-4, Rick C wrote:

On Friday, November 1, 2019 at 11:06:29 AM UTC-4, Whoey Louie wrote:

If we were to start from scratch, I see
compelling advantages to going with 240V as the standard for all
loads, eg an electric kettle could heat twice as fast. I see
some small advantages, eg the 50 cents above, but I sure
don't see a compelling advantage to 3 phase for homes.

Your assumption that a kettle would boil twice as fast is based on an assumption that the same size wire and so the same current capacity would be used. I believe in the UK circuits can be typically 9 or 13 amps, so smaller than the 15 or 20 we typically use.

IDK what they do over there. But yes, I was assuming that we'd
continue to use the same size minimum conductors, so a 15A
circuit would then deliver twice the power.

If we weren't going to save on the cost of wiring there is no real reason to convert.

Who said anything about converting? I said if we were starting from
scratch.




Boiling water for tea faster is not a very compelling reason to worry with even thinking about which way to go.

It's not just boiling tea faster. Many older homes have only one 15A
circuit for the kitchen counters. Plug in one microwave, you've
only got a few hundred watts left. Even in newer homes with two
circuits, put a microwave or one of those new convection counter
top widgets on it, that circuit is near tapped out. With 240V
you could double the power with the same size conductors. I'm just
saying that apparently people aren't killing themselves in Europe
with 220 volts and it has clear advantages, so it would be logical,
IMO, to go with 240V instead of 120V if we were starting from
scratch.

 

[Rick C]

On Friday, November 1, 2019 at 12:34:52 PM UTC-4, keith wright wrote:

On Friday, 1 November 2019 08:32:00 UTC-7, Rick C wrote:
...

Your assumption that a kettle would boil twice as fast is based on an assumption that the same size wire and so the same current capacity would be used. I believe in the UK circuits can be typically 9 or 13 amps, so smaller than the 15 or 20 we typically use.
...

Strictly speaking the circuits are usually 30Amp (wired as a ring main) with a local fuse inside the plug that depends upon the load. It can be up to 13A.

kw

So what gauge wire is required in the house? I would think something capable of handling 30 amps. But that's a matter of how they run the wires really and not actually related to the voltage issue.

In the US we run a separate wire to each room or a few rooms (like bedrooms) with a 15 amp fuse. Kitchens usually have a separate circuit and bathrooms often have separate circuits because of being on a GFCI breaker. I think the UK calls these RCDs.

On 240 volts single phase the amperage could be about 8 with smaller gauge wiring.

--

Rick C.

+++- Get 1,000 miles of free Supercharging
+++- Tesla referral code - https://ts.la/richard11209

 

[Rick C]

On Friday, November 1, 2019 at 12:06:22 PM UTC-4, Whoey Louie wrote:

On Friday, November 1, 2019 at 11:32:00 AM UTC-4, Rick C wrote:
On Friday, November 1, 2019 at 11:06:29 AM UTC-4, Whoey Louie wrote:

If we were to start from scratch, I see
compelling advantages to going with 240V as the standard for all
loads, eg an electric kettle could heat twice as fast. I see
some small advantages, eg the 50 cents above, but I sure
don't see a compelling advantage to 3 phase for homes.

Your assumption that a kettle would boil twice as fast is based on an assumption that the same size wire and so the same current capacity would be used. I believe in the UK circuits can be typically 9 or 13 amps, so smaller than the 15 or 20 we typically use.

IDK what they do over there. But yes, I was assuming that we'd
continue to use the same size minimum conductors, so a 15A
circuit would then deliver twice the power.




If we weren't going to save on the cost of wiring there is no real reason to convert.

Who said anything about converting? I said if we were starting from
scratch.

Either way. No point if it doesn't save money. That is the point of 3 phase. While it makes many things more complex, it saves on copper costs.

Boiling water for tea faster is not a very compelling reason to worry with even thinking about which way to go.

It's not just boiling tea faster. Many older homes have only one 15A
circuit for the kitchen counters. Plug in one microwave, you've
only got a few hundred watts left. Even in newer homes with two
circuits, put a microwave or one of those new convection counter
top widgets on it, that circuit is near tapped out. With 240V
you could double the power with the same size conductors.

Now you ARE talking about converting.

I'm just
saying that apparently people aren't killing themselves in Europe
with 220 volts and it has clear advantages, so it would be logical,
IMO, to go with 240V instead of 120V if we were starting from
scratch.

Anyone who suggests 240 volts is significantly more dangerous than 120 volts AC is likely blustering. I haven't found any objective information about it.

I wouldn't have a problem with using 240 volts for common appliances. But the US sockets blow! The UK seems to have some decent ones and integrating a switch is a good idea along with the fuse in the plug. Meanwhile the best we can do is to add shutters to prevent insertion of small metal probes.

I would support the addition to every outlet of a locking, non-conductive plug that hangs on a leash so it's always there to be used.

--

Rick C.

++-+ Get 1,000 miles of free Supercharging
++-+ Tesla referral code - https://ts.la/richard11209

 

[Rick C]

On Friday, November 1, 2019 at 2:00:24 PM UTC-4, keith wright wrote:

On Friday, 1 November 2019 10:38:46 UTC-7, Rick C wrote:
..
...

Strictly speaking the circuits are usually 30Amp (wired as a ring main) with a local fuse inside the plug that depends upon the load. It can be up to 13A.

kw

So what gauge wire is required in the house? I would think something capable of handling 30 amps. But >that's a matter of how they run the wires really and not actually related to the voltage issue.

Commonly 2.5sqmm wire is used in a ring-main configuration so the current is provided by two paths. A 30A fuse or 32A CB protects the circuit.

(https://en.wikipedia.org/wiki/Ring_circuit)

I've never been a believer in the redundancy thing if you can't verify that the redundancy has not been compromised. once a connection opens up or develops a high resistance, the two paths are separated and no more redundancy with no way to detect it. Such redundancy is fine for things that can be properly inspected. For hidden features it would seem to provide a false sense of security.

--

Rick C.

++++ Get 1,000 miles of free Supercharging
++++ Tesla referral code - https://ts.la/richard11209

 

[keith wright]

On Friday, 1 November 2019 10:38:46 UTC-7, Rick C wrote:
...

...

Strictly speaking the circuits are usually 30Amp (wired as a ring main) with a local fuse inside the plug that depends upon the load. It can be up to 13A.

kw

So what gauge wire is required in the house? I would think something capable of handling 30 amps. But >that's a matter of how they run the wires really and not actually related to the voltage issue.

Commonly 2.5sqmm wire is used in a ring-main configuration so the current is provided by two paths. A 30A fuse or 32A CB protects the circuit.

(https://en.wikipedia.org/wiki/Ring_circuit)

kw

In the US we run a separate wire to each room or a few rooms (like bedrooms) with a 15 amp fuse. Kitchens usually have a separate circuit and bathrooms often have separate circuits because of being on a GFCI breaker. I think the UK calls these RCDs.

On 240 volts single phase the amperage could be about 8 with smaller gauge wiring.

--

Rick C.

+++- Get 1,000 miles of free Supercharging
+++- Tesla referral code - https://ts.la/richard11209

 

Sorry, I am not reading the whole thread so it may have been said.

The main thing in residential is 110, which is now 125.There are usually only a few 220 lines in a US house.

Businesses are another story, they might have three phase. But many now use a delta wye configuration and that provides a 110 line.

Remember even though the might pour fifty tons of steel a day the still have an office.

That 75 watts is lees than an amp even at 110, so you don't need a dedicated circuit or number eight wire or any of that shit.

My considered advice is to go with 110. Even if all you have is 220, in this country it is balanced so you can just take of one side and the neutral and you got it. In fact you could make a special cord for that real cheap.

Now if you are dealing with three phase that is not delta wye then you need a transformer. I don't know where you are at but it should be cheap in the UK and other 220/240 places. So what you do is get these transformers which will be a secondary rated for 240, but you want higher than what it says because it is only 208. It works out to something like 87%. So you choose one with a secondary that much higher. And there is no safety issue at all running it below its ratings. And none of this shit will be expensive if you only need about an amp.

 

On Fri, 1 Nov 2019 10:32:49 -0700 (PDT), Rick C
<gnuarm.deletethisbit@gmail.com> wrote:

On Friday, November 1, 2019 at 12:06:22 PM UTC-4, Whoey Louie wrote:
On Friday, November 1, 2019 at 11:32:00 AM UTC-4, Rick C wrote:
On Friday, November 1, 2019 at 11:06:29 AM UTC-4, Whoey Louie wrote:

If we were to start from scratch, I see
compelling advantages to going with 240V as the standard for all
loads, eg an electric kettle could heat twice as fast. I see
some small advantages, eg the 50 cents above, but I sure
don't see a compelling advantage to 3 phase for homes.

Your assumption that a kettle would boil twice as fast is based on an assumption that the same size wire and so the same current capacity would be used. I believe in the UK circuits can be typically 9 or 13 amps, so smaller than the 15 or 20 we typically use.

IDK what they do over there. But yes, I was assuming that we'd
continue to use the same size minimum conductors, so a 15A
circuit would then deliver twice the power.




If we weren't going to save on the cost of wiring there is no real reason to convert.

Who said anything about converting? I said if we were starting from
scratch.

Either way. No point if it doesn't save money. That is the point of 3 phase. While it makes many things more complex, it saves on copper costs.

One significant advantage is that you easily get a rotating field, so
a 3 phase motor is simple, no need for special arrangements to get the
motor started. Before VFDs became common, this was an important issue.

One significant problem especially in the US is the low voltages
(120/240 V) and hence large currents. This means that the distribution
transformer (pole pig) must be very close to the load, which requires
a dense medium voltage (14 kV?) network.

The low voltages can be blamed on Edison and his incandesce lamps that
initially had a low voltage rating. Later versions could handle
voltages over 200 V, so the rest of the world adapted 220-240 V for
lamp loads.

Lets speculate what the distribution would look today, if designed
from scratch.

Now that the incandesce lamps are gone, a much higher voltage could
be selected.

These days a 750 to 1500 Vdc distribution voltage could be selected.
If 3 phase is needed for some motors, a VFD from +/-350 Vdc could be
used to generate 230/400 V with low distortion. With a DC feed no need
for a PFC. For small loads simple DC/DC converters could be used.
These would be simpler than current inverters, since there would be no
need to generate a sine voltage.

 

[Michael Terrell]

On Friday, November 1, 2019 at 10:48:27 AM UTC-4, Lasse Langwadt Christensen wrote:

fredag den 1. november 2019 kl. 14.44.24 UTC+1 skrev Michael Terrell:
On Thursday, October 31, 2019 at 4:05:29 PM UTC-4, upsid...@downunder.com wrote:
On Thu, 31 Oct 2019 21:00:43 +0100, Gerhard Hoffmann <dk4xp@arcor.de
wrote:


When we were students, we also had a ham radio linear amplifier
that ran on 3 phase. 2 QB5/1750 tubes, 5.5KV @ 1A+.
That was not exactly legal, but fun. Statute-barred a long time.

At those voltages it is hard to get any big storage capacitors, so
using a 6 pulse, three phase rectifier and the anode voltage is smooth
enough (4 % ripple).

4% would have a noticeable hum and never meet FCC standards. HV capacitors were available for big transmitters. They were large, oil filled with ceramic insulators. Some weighed several hundred pounds, but were still in daily service over 50 years later. Phase correction capacitors used in power distribution were similar but usually lower capacitance.


you can get from three phases to six phases with just transformers, I think a 12 pulse 6-phase rectifier is ~1% ripple

I have never seen that configuration in any transmitter, and I worked on some that drew over 200KW for the final tubes. Capacitors are cheaper than the additional components, and they help filter out line transients that extra diodes don't.

 

[Piglet]

On 31/10/2019 14:01, DecadentLinuxUserNumeroUno@decadence.org wrote:

I have not seen "115V" listed since the fucking sixties!

Yes. Sometimes saw labels showing "117V" which seems quaint. I guess
there was a kind of sense as 117 is mid-way 110-125.

piglet

 

[Joseph Gwinn]

On Nov 1, 2019, upsidedown@downunder.com wrote
(in article<o4uorep0bid2is7pl9i6m5ip7s78k9rlgq@4ax.com&gt:

On Fri, 1 Nov 2019 10:32:49 -0700 (PDT), Rick C
gnuarm.deletethisbit@gmail.com> wrote:

On Friday, November 1, 2019 at 12:06:22 PM UTC-4, Whoey Louie wrote:
On Friday, November 1, 2019 at 11:32:00 AM UTC-4, Rick C wrote:
On Friday, November 1, 2019 at 11:06:29 AM UTC-4, Whoey Louie wrote:

If we were to start from scratch, I see
compelling advantages to going with 240V as the standard for all
loads, eg an electric kettle could heat twice as fast. I see
some small advantages, eg the 50 cents above, but I sure
don't see a compelling advantage to 3 phase for homes.

Your assumption that a kettle would boil twice as fast is based on an
assumption that the same size wire and so the same current capacity woul

be used. I believe in the UK circuits can be typically 9 or 13 amps, so
smaller than the 15 or 20 we typically use.

IDK what they do over there. But yes, I was assuming that we'd
continue to use the same size minimum conductors, so a 15A
circuit would then deliver twice the power.




If we weren't going to save on the cost of wiring there is no real reaso

to convert.

Who said anything about converting? I said if we were starting from
scratch.

Either way. No point if it doesn't save money. That is the point of 3
phase. While it makes many things more complex, it saves on copper costs.

One significant advantage is that you easily get a rotating field, so
a 3 phase motor is simple, no need for special arrangements to get the
motor started. Before VFDs became common, this was an important issue.

True.

..

One significant problem especially in the US is the low voltages
(120/240 V) and hence large currents. This means that the distribution
transformer (pole pig) must be very close to the load, which requires
a dense medium voltage (14 kV?) network.

Possibly.

..

The low voltages can be blamed on Edison and his incandescent lamps that
initially had a low voltage rating. Later versions could handle
voltages over 200 V, so the rest of the world adapted 220-240 V for
lamp loads.

Not true.

I´ve read some of the analyses from the day. Edison was optimizing the
total cost of a local DC generator feeding a bunch of lighting circuits,
where multiple incandescent lamps in parallel were the only load. Electric
lights were the killer app for electricity. He was optimizing the whole
thing, not just the lamps. The economic optimum was broad, centered around
100 volts.

I have not seen the analyses from Europe when they settled on 220 V (versus
110 V), but I´m assuming that they were optimizing again, and cost of the
wiring plant weighed more heavily in their calculations. Small electric
motors may have also entered into the analysis. Also, retrofitting power
wires in existing masonry and stuccoed structures is easier if the wires are
small and flexible, suited to being grouted into grooves chiseled into solid
masonry walls.

War story: I lived in Sweden in the mid 1970s, designing circuitry for a
small company. Prototyping (vector board, tinned solid wire, axial-leaded
components) involved a lot of hand soldering, and the smoke gave me raging
headaches, so I asked my business partner if he had a fan with speed control
that I could use to blow the smoke away. He said yes, and disappeared into
the sub-basement of the large apartment block in Stockholm where we were
located, and came back with this beautiful old enameled iron and brass desk
fan, which a built-in rheostat speed control It had not been used in decades,
so I cleaned and oiled it, and then tested it. It just hummed a bit and the
blades moved slowly. Hmm. Then it hit me - why was this beautiful fan in the
dusty sub-basement? And the iron was not laminated. Looked at its nameplate -
Gleichstrom! It was made in the days when utility power was DC, but it was
too well made (and expensive) to be thrown away. Sweden converted to AC power
circa 1920, so that beautiful fan had lain in storage for almost sixty
years. Anyway, the march of technology saved the day. I made a four-diode
full wave rectifier bridge from some 1N4005 diodes and heat-shrink tubing,
and installed the bridge in the fan base. Bingo! I used that fan from then
on.

Epilog: In 2017, I visited my now retired business partner (now in his mid
eighties). He still has that fan, and it still works perfectly. Must be at
least a century old by now.

They really don´t make them like they used to....

Joe Gwinn

 

[Whoey Louie]

On Friday, November 1, 2019 at 3:28:31 PM UTC-4, jurb...@gmail.com wrote:

Sorry, I am not reading the whole thread so it may have been said.

The main thing in residential is 110, which is now 125.There are usually only a few 220 lines in a US house.

It's actually 120/240 and has been for more than half a century in the USA,
at least in any places that matter.

Businesses are another story, they might have three phase. But many now use a delta wye configuration and that provides a 110 line.

Delta wye? There is delta and there is wye. Wye give you 120 volts as one
option. Delta would give you 208. But again, if he's talking about some
mass market widget, the largest market for a 75W plug-in widget is 120V.

 

[Piotr Wyderski]

Rick C wrote:

> That's well above average in the US. Are you getting juice from a nuke plant?

No, we have soclialism to build. Currently the price of 1MWh is 168PLN
on the wholesale market, 500-600 PLN for end users. The difference is
made of multiple taxes and other "quality fees".

Best regards, Piotr

 

[Whoey Louie]

On Friday, November 1, 2019 at 1:32:55 PM UTC-4, Rick C wrote:

On Friday, November 1, 2019 at 12:06:22 PM UTC-4, Whoey Louie wrote:
On Friday, November 1, 2019 at 11:32:00 AM UTC-4, Rick C wrote:
On Friday, November 1, 2019 at 11:06:29 AM UTC-4, Whoey Louie wrote:

If we were to start from scratch, I see
compelling advantages to going with 240V as the standard for all
loads, eg an electric kettle could heat twice as fast. I see
some small advantages, eg the 50 cents above, but I sure
don't see a compelling advantage to 3 phase for homes.

Your assumption that a kettle would boil twice as fast is based on an assumption that the same size wire and so the same current capacity would be used. I believe in the UK circuits can be typically 9 or 13 amps, so smaller than the 15 or 20 we typically use.

IDK what they do over there. But yes, I was assuming that we'd
continue to use the same size minimum conductors, so a 15A
circuit would then deliver twice the power.




If we weren't going to save on the cost of wiring there is no real reason to convert.

Who said anything about converting? I said if we were starting from
scratch.

Either way. No point if it doesn't save money. That is the point of 3 phase. While it makes many things more complex, it saves on copper costs.


Boiling water for tea faster is not a very compelling reason to worry with even thinking about which way to go.

It's not just boiling tea faster. Many older homes have only one 15A
circuit for the kitchen counters. Plug in one microwave, you've
only got a few hundred watts left. Even in newer homes with two
circuits, put a microwave or one of those new convection counter
top widgets on it, that circuit is near tapped out. With 240V
you could double the power with the same size conductors.

Now you ARE talking about converting.

Geez, you want to argue about everything. First you claim I was
talking about converting. I clearly said I was not. Now you're
claiming I'm taking about it again. Nothing in the above says
anything about converting. Modern kitchen appliances use more
power, eg microwaves and kitchens have more of them. If we used
240V, it makes it easier and less expensive to deliver that power.
Nothing there about converting what is already there, it's beyond
ridiculous to even be thinking about that.

I'm just
saying that apparently people aren't killing themselves in Europe
with 220 volts and it has clear advantages, so it would be logical,
IMO, to go with 240V instead of 120V if we were starting from
scratch.

Anyone who suggests 240 volts is significantly more dangerous than 120 volts AC is likely blustering. I haven't found any objective information about it.

I wouldn't have a problem with using 240 volts for common appliances. But the US sockets blow! The UK seems to have some decent ones and integrating a switch is a good idea along with the fuse in the plug. Meanwhile the best we can do is to add shutters to prevent insertion of small metal probes.

I would support the addition to every outlet of a locking, non-conductive plug that hangs on a leash so it's always there to be used.

You want them, you buy them and install them. Leave me and
my receptacles alone.