Hi Experts,
I have a European LG washing machine model # WD-90150(5)FB. It was designed for 240V, 50 Hz.
Does anyone know what parts need to be changed to make it run on 240V, 60 Hz and where could I get a wiring diagram?
I already checked with the US: snipped-for-privacy@lge.com and it was a complete waste of time. They seem to know nothing.
TIA
RF
I don't know this particular model, but in general, I can only think of two parts which might care in a European machine:
The pump out motor is probably a shaded pole motor. On 60Hz, it will run faster but with less power. This probably won't matter providing you don't expect it to pump the outlet water up to any great height (although you must still loop the outlet hose up to the top of the machine, or it will drain out whilst it is trying to fill).
Secondly some machines have mechanical timers which run some parts of the sequence using a synchronous motor - these would run 20% shorter. However, the one and only picture I can see on the web (which is too small to be sure) looks like the unit has microprocessor control, in which case that will not be an issue.
The main drum motor will be a universal motor, so it might suffer a slight reduction in power. However, these motors usually have plenty of spare power and it will probably be servo controlled, so this probably won't notice, or if it does, it would be only as a longer run-up time, and possibly a slight reduction in the top spin speed, but even that's unlikely.
However, not knowing this particular machine, there may well be things I've overlooked.
Just curious.... Were you planning to connect this machine somewhere in North America? Is this a permanent installation?
If so, there may be some other issues such as connectors and grounding that you might wish to consider. Although 240 V. 60 Hz is readily available in N.A., the residential circuits and outlets are usually designed specifically for dryers and ranges at 30A and up to around
50A respectively. Unless you are planning to create a kluge installation, you will have to deal with the differences in connectors and probably wire up one yourself.Also, be aware that 240V. Euro appliances are designed for systems that have one hot (at 240V) and one neutral (at earth potential) and usually a separate ground wire.
The NA system is slightly different in that the 240 V. circuits are two hot wires (240 V. with respect to each other and 120 volts each one to earth potential). There is usually but not always (in new installations) a separate ground wire.
I personally would not want to install or operate a washing machine unless I was sure that it had a good, safe and legal ground connection.
The general recommendation is to buy large appliances rated for their intended place of use, but perhaps you have a good reason for doing this?
Beachcomber
The EU washing machine would probably expect to be in a circuit protected at up to 16A (max load is probably 10A).
That's not the case. All Euro appliances have to work on all systems which exist across Europe, and those include systems where neither supply conductor is a neutral, and systems where it is not defined which supply conductor is the live (hot) and which is the neutral. It will need a ground connection as you say.
You may have a problem getting European washing detergent designed for profiled low temperature washes in the US. The machine will have high temperature washes too, but European washing machines are not designed for US soap powders.
Andrew:
Sorry, I was not aware that some Euro systems have neither supply conductors designated as a neutral. I'd be interested in knowing what countries use such systems.
Is it not true that the Euro authorities were trying to standardize their electrical systems?
Beachcomber
Much of Europe doesn't have a polarised supply at socket outlets. Either the plug is reversible (Shucko) or it's not defined which of the two supply conductors is live and neutral (French/Belgium sockets). The UK does have polarised socket outlets though.
There are also supplies in some European countries where neither supply conductor is neutral. There are two schemes which give rise to this -- supply from a corner grounded delta winding where your supply conductors are the two ungrounded corners (used in some areas of some Scandinavian countries), and "IT" systems (Isolé Terre, International standard IEC 60364) where the supply doesn't have any connection to earth (except possibly just a high impedance to stop the supply floating up to the levels of the HV primary by capacitive coupling), used in a few areas of France I've heard.
It's done mainly by writing a standard which encompasses all the pre-existing variants, and requiring that all EU appliances must work with all these supply variants. This means EU appliances can be sold/used anywhere in the EU, without replacing half EU's supply infrastructure, which would clearly be non-viable.
There is also harmonisation going on -- in the UK we recently changed our premises wiring colour code to the EU standard. This was put off for years because one of our phase colours (blue) is the harmonised neutral colour, so there's plenty of scope for big bangs if electricians screw up. Also, our colour coding of 3- phase gives you the phase rotation, which you didn't get from the harmonised colour codes.
Andrew:
Thanks for the info.
In the US, corner-grounded 3-phase systems exist but they are rare and mostly found in places like rural irrigation pump installations where some sort of derived ground is better than no ground at all.
Yes I've heard about that harmonized color code with your what was it the UK "blue" hot wire, which is now the color of the official Euro neutral, is it not? What could possibly go wrong? ... as they say... If you ask me, it kind of defeats the purpose of having color codes if they are going to be all mucked up.
I'm curious how that came about. You would think that they could pick a new color. Pink would have been my choice for neutral or dare I say it "white"... Or would that have been too similar to the electric system in the United States?
I'll bet the French were behind this. I had the opportunity to live in a French apartment for a year and I learned that I was really a spoiled American that took good wiring practices for granted. That God-awful f*%$!! disjoncter would cut off my power simply because it thought I was using too much electricity at one time. I wasn't overloading the system at all. The landlord said that this was a normal occurrence. I was just being a typical resident that wanted to take a hot bath every day.
Sorry to vent on this... :) It still brings back bad memories sometimes.
Beachcomber
Rare even in the one or two EU countries which use them, I believe.
There aren't all that many cases of people picking up a building and moving it to another country either.
White was/is used pretty universally to indicate a clean ground (i.e. a signal ground in telecoms/datacoms, rather than a safety ground for fault currents). Pre-haromisation, the Germans used red for safety ground -- lots of scope for fatal screw-ups when kit moved to a number of other countries.
In France, that's usually a 500mA RCD (GFI).
Sounds like the heating element was corroded through the casing and leaking to ground.
French wiring (unless it's anchient) isn't normally too bad, certainly seen much worse elsewhere. The French have some of the most sophisticated electricity meters I've seen (you can cycle through about 10 different types of measurement on the front panel), and all read remotely of course, and remotely signalled to switch on/off night time storage heating devices based on loading on the national supply).
On Sat, 28 Oct 2006 19:40:56 GMT Beachcomber wrote: | |>> Also, be aware that 240V. Euro appliances are designed for systems |>> that have one hot (at 240V) and one neutral (at earth potential) and |>> usually a separate ground wire. |>
|>That's not the case. All Euro appliances have to work on all |>systems which exist across Europe, and those include systems |>where neither supply conductor is a neutral, and systems |>where it is not defined which supply conductor is the live (hot) |>and which is the neutral. It will need a ground connection as |>you say. |>
| Andrew: | | Sorry, I was not aware that some Euro systems have neither supply | conductors designated as a neutral. I'd be interested in knowing | what countries use such systems.
Some remote rural areas have legacy 220/127 or 220/110 systems that were likely in place well before WW2. I have heard of this in Spain and Norway. Some people believe they are safer because of the lower wire to ground voltage. They are certainly less safe on lights that allow contact to one of the conductors. Many countries outside of Europe have these systems, including the Middle East and Africa.
Deal with it.
| Is it not true that the Euro authorities were trying to standardize | their electrical systems?
The standard is 230 volts. They are allowing 220 to 240 to stay.
On 28 Oct 2006 20:19:10 GMT Andrew Gabriel wrote: | In article , | snipped-for-privacy@notreal.none (Beachcomber) writes: |> Andrew: |> |> Sorry, I was not aware that some Euro systems have neither supply |> conductors designated as a neutral. I'd be interested in knowing |> what countries use such systems. | | Much of Europe doesn't have a polarised supply at socket | outlets. Either the plug is reversible (Shucko) or it's | not defined which of the two supply conductors is live | and neutral (French/Belgium sockets).
The French sockets sure look polarized, to me, as long as you do use a grounded plug. Using an old ungrounded plug would be an issue.
| The UK does have polarised socket outlets though.
And more foot injuries.
|> Is it not true that the Euro authorities were trying to standardize |> their electrical systems? | | It's done mainly by writing a standard which encompasses | all the pre-existing variants, and requiring that all EU | appliances must work with all these supply variants. This | means EU appliances can be sold/used anywhere in the EU, | without replacing half EU's supply infrastructure, which | would clearly be non-viable.
But they still have to supply local plugs on cords.
| There is also harmonisation going on -- in the UK we | recently changed our premises wiring colour code to the | EU standard. This was put off for years because one of | our phase colours (blue) is the harmonised neutral | colour, so there's plenty of scope for big bangs if | electricians screw up. Also, our colour coding of 3- | phase gives you the phase rotation, which you didn't get | from the harmonised colour codes.
But will they ever be harmonizing the plugs?
It's true you can't reverse the plug. However, it is not defined which is the live or neutral contact. In pretty well all two-way adaptors and double socket outlets, the two sockets are hardwired the opposite way round, so it's not like there's even any unofficial convention.
Eh? You mean from standing on a loose plug laying on the floor? ;-). At least no one puts enough weight on it to damage the plug, which I do see in other countries.
Usually just supply the appropriate IEC cordset, or sometimes several different ones (they cost nothing in any quantities).
There were many(5?) failed attempts back when I was following this, but I've not been following this for some years now. The conditions the EU imposed were that no country was to see a reduction in safety as a result of adopting a harmonised plug, and no currently used plug could be adopted as it would give unfair economic advantage to countries which already used it (and the safety angle also precludes adopting any currently used plug).
However, it's not just about the plug -- the plug is just one component in the supply infrastructure, and it is designed around the way the rest of the supply infrastructure works. There are more different supply infrastructures in Europe than there are countries in Europe, and you can't just use the plug from one with the infrastructure from another, or you find you've got no ground connection, or no fault current protection, etc. (Actually, there are a number of areas in Europe where this does already happen.) No one is about to go around rewiring Europe.
The most recent case of a country redesigning its appliance supply infrastructure was the UK in 1946 when it switched over to 13A sockets and the ring circuit, and that took ~40 years to implement, starting at a time when we had a small number of appliances and existing wiring systems with a lifespan of 40 years. We now have probably ten times as many appliances and installed wiring systems with estimated lives of well over 100 years, so they aren't going to change anytime soon.
I've never heard of this in Europe, and these are not supplies which I can recall any country's representitaves claimed they use. Nearest I can think of for the 220/127 is 220 Delta which I mentioned in another post, but there's no 127 component to that.
What you can sometimes find are 480/240V supplies in UK, which is like the US residential scheme but with twice the voltage (and 440/220V versions in other EU countries). These are used in outlaying areas where large machinary (farms, etc) need more than 240V, but there's no 3-phase HV distribution. This is rare, because HV distribution is 3-phase nearly everywhere across Europe.
My thanks to all for a great discussion.
I bought this machine in Portugal, where I used it for most of a year and yes, I want to use it in North America. It works extremely well and is very efficient - A rating. I was hoping to be able to buy whatever components it took to adapt it to the 60 Hz. From this discussion, it appears that I might not have to do much work on it. I wrote to LG in Italy about the components needed and, as I had guessed, I received no reply.
The electric plug on the machine is a standard 240V 2-prong that is not polarized. The ground is in two slots on opposite sides of the plug, so it is symmetric i.e. it can be inserted into the outlet one way or rotated 180 degrees and re-inserted. The timer is digital and the machine makes about 6 or 7 cuckoo sounds when finished washing :-) Cute!
Markings on the plug: SE SHIN SEE 72GE
10/16A, 250V. and the letters D, FI, S and N in circles, and in other loops OVE, Cebec and KemaEur.Thanks again for the help.
RF
| There were many(5?) failed attempts back when I was following | this, but I've not been following this for some years now. | The conditions the EU imposed were that no country was to | see a reduction in safety as a result of adopting a harmonised | plug, and no currently used plug could be adopted as it | would give unfair economic advantage to countries which | already used it (and the safety angle also precludes | adopting any currently used plug).
Then maybe they should adopt one of the designs I was coming up with for the "new world power system" I mentioned in another thread based on the notion of going back in time and changing everything.
One of the designs has a full circle metal shell/shroud, kind of like the shield of a male RS-232 connector, but larger, in a circle, and longer than the pins. It might be about the size of a GR-874 RF conenctor. The wall receptacle is flat, with an opening for the shell/shroud which also serves as the earthing/grounding contact. Insertion of the shell/shroud will also press back nylon tabs on the inner side that opens up the pin holes. The pins can't even get in the holes until the shroud is in far enough to move the cover tabs _and_ shield any possible arcs. The pins would be bladed, not round, much like the British ones, but turned parallel like in the USA. The blades would have a short length for low current uses and a longer length for higher current uses in the direction that is 90 degrees from the spacing between pins. This would allow the low current plug to be used in a higher current outlet. Also, low current outlets (but not higher current outlets) would have a couple small keyholes at opposides sides of the shroud opening to allow a plug that has notches to be used exclusively on the low current outlet. This key could be like the nuts of a BNC female connector.
| However, it's not just about the plug -- the plug is just | one component in the supply infrastructure, and it is designed | around the way the rest of the supply infrastructure works. | There are more different supply infrastructures in Europe than | there are countries in Europe, and you can't just use the plug | from one with the infrastructure from another, or you find you've | got no ground connection, or no fault current protection, etc. | (Actually, there are a number of areas in Europe where this does | already happen.) No one is about to go around rewiring Europe.
That can certainly be a problem, especially the no fault current protection.
Where the wiring doesn't have the proper grounding, it should leave the old style local outlet/plug design in place.
| The most recent case of a country redesigning its appliance | supply infrastructure was the UK in 1946 when it switched over | to 13A sockets and the ring circuit, and that took ~40 years to | implement, starting at a time when we had a small number of | appliances and existing wiring systems with a lifespan of 40 years. | We now have probably ten times as many appliances and installed | wiring systems with estimated lives of well over 100 years, so | they aren't going to change anytime soon.
That's the biggest limitation of the change anywhere. If a new design were to be adopted, clearly it would have to be expected to take decades to change over just as the UK saw. About 10 years ago I was in a house that still had a circa 1900 knife switch as the main disconnect and no main fuse. There were about six porcelain screw shell fuse holders on the same wood board and K&T circuits running up from there. While it certainly could use some rewiring, that probably won't happen for a while.
On 29 Oct 2006 09:07:18 GMT Andrew Gabriel wrote: | In article , | snipped-for-privacy@ipal.net writes: |> |> Some remote rural areas have legacy 220/127 or 220/110 systems that |> were likely in place well before WW2. I have heard of this in Spain |> and Norway. | | I've never heard of this in Europe, and these are not supplies | which I can recall any country's representitaves claimed they | use. Nearest I can think of for the 220/127 is 220 Delta which | I mentioned in another post, but there's no 127 component to that.
I've read that a few places did have some legacy 220/127. Remote rural locations of Norway and Spain were specifically mentioned. Perhaps these were attempts to have a lower voltage relative to ground?
I do know some countries outside of Europe have this, like Saudi Arabia.
| What you can sometimes find are 480/240V supplies in UK, which | is like the US residential scheme but with twice the voltage | (and 440/220V versions in other EU countries). These are used | in outlaying areas where large machinary (farms, etc) need | more than 240V, but there's no 3-phase HV distribution. This | is rare, because HV distribution is 3-phase nearly everywhere | across Europe.
Three phase used to be widely available in the US ... where there was any electricity at all. That was before "Rural Electrification" which ended up choosing single phase for everything. So we ended up with a lot of 240 volt, instead of 208 volt, appliances. So three phase is actually quite undesirable (at least I think so).
I'd be happen if the USA were to switch to 480/277 for everything. But that'd never happen.
| I have a European LG washing machine model # WD-90150(5)FB. It was designed | for 240V, 50 Hz. | | Does anyone know what parts need to be changed to make it run on 240V, 60 Hz | and where could I get a wiring diagram? | | I already checked with the US: snipped-for-privacy@lge.com and it was a complete | waste of time. They seem to know nothing.
The people that really know anything, engineers, are kept isolated in special places called cubicles, incommunicado with the rest of the world.
About a year ago I was talking to a guy who sells "220 volt" appliances in the USA that would normally be available for 120 volts. I was asking him about how things like clothes dryers, which need a very specific tumbling speed, handled the different between 50 Hz and 60 Hz, since a few countries (e.g. Brazil) do have 240 volts at 60 Hz. He said that a lot of models could be easily converted. The motor and drum each had two belt positions, one smaller and one larger. In 50 Hz countries the belt would be on the larger rim of the motor and the smaller rim of the drum. In 60 Hz countries, that would be reversed with the same belt size. A washing machine would involve more forces, so I don't know if they have belts as such, but maybe a chain?
What I am looking for is a clothes dryer that everything within uses only
240 volts and nothing at all uses 120 volts. This would allow it to work without a neutral. I was thinking maybe a European/Asian model might be what I am looking for.For a washing machine, I'm looking for similar, but also with built-in water heating so that it can run directly from only cold water. I would expect this to require more power, possibly more than the dryer. I had seen some that stated they had heaters, but now I think they are just supplementary heaters that allow using hot water tanks that operate at lower temperatures (below 50C).
I'm also looking for 240 volt versions of in-sink garbage disposal/grinder. As their motors are usually over 1/4 HP, NEC 210.6(a)(2) would not be an issue to use 240 volts. That rule specifies that no more than 120 volts may be used for cord-and-plug connection loads unless the load exceeds
1440 VA or is 1/4 HP or more.
Phil:
(this is long)
Three phase power IS widely available in the USA, even in many rural districts. Just about every PUD in my region, (the Pacific Northwest), has a special tariff for true three-phase service.
It's just not available everywhere and unlike continental Europe, the houses in the rural US are often not clustered together in settlements and crossroads. US farmhouses are more often found in isolated areas. Most of these isolated areas are economically served by single-phase distribution feeders.
The US Rural Electrification Administration decided during the 1930's that a split phase 220/110 V 60 Hz was the best compromise in economy, offering a choice of high and low voltages, safety, and compatibility with the existing system of voltages, plugs and sockets.
There was some concern about farmers and rural industrial users ability to run high horsepower motors (over 10 HP) for their needs, but the repulsion start - induction run motor was readily available and the technology was never a barrier to a higher horsepower when they were required.
You present an interesting discussion for what the "best" system would be if all the world had the ability to start over and develop "new" standards from scratch.
One such way that the "best" system can be described is by its simplicity and whether it has been successful from a standpoint of widespread adoption, safety and economy.
For example, one might criticize the US-North American system of plugs and sockets as being less rugged than the British or Euro-Continental counterparts like the "Shuko" system, for example.
As far as I can determine, the history of the European system of multiple incompatible plugs and sockets is simply a big mess. I know they are trying to standardize things, but holy cow, it's enough to drive you nuts.
Looking at it another way, the US NEMA flat, simple sockets are inexpensive and aesthetically pleasing. They don't need on-off switches on them for safety like some of the outlets I've seen in the UK. The plugs mate snuggly with the socket yet there is seldom the risk of damaging the outlet if you trip over a flex (cord). The plug will simply come out of the socket if it yanked hard enough. Also, you get more of outlets per square inch (or cm) of outlet strip, a distinct advantage of for those of us whose home offices power needs runneth over.
Although the Euro pins can theoretically carry more current then the flat US blades, the blades are generally safe enough, easy to align, and allow for an aesthetically pleasing, relatively flat outlet that can be mounted in a horizontal or vertical position. They also are
100% backwards compatible in that the 3 - prong outlets accept 2 or 3 prong plugs. The US-NA system allows for enforcement of hot-neutral polarity but it is compatible with older or (newer) double-insulated appliances that don't use it.Similarly, the widespread adoption of cheap (about $5 each) outlet-substitute GFCI (ground fault circuit interrupters) has greatly increased the safety of branch circuits in the US. With this system, customers don't need to spring for an expensive and potentially dangerous centrally-located RDC that will kill all or most of all the power to a residence in the event of a simple fault.
No, even in a climate of rising copper prices, going to higher-and-higher voltages sounds desirable (theoretically, to a trained electrical-engineer perhaps), but I don't think the USA would ever switch to 480/277. Why stop there, how about 830/480? (I could run my vacuum cleaner with bell wire perhaps? :)
My point is that, at least with 120 volts, your life is less dependant on the failure of one RDC device. You can still hope for the downstream GFCI or a short circuit to ground to open up the breaker.
If you must take a shock, 120 V. feels a whole lot less intense than
240 volts and the difference just might be for you to be able to let go before your heart kicks off.Also note that with the US-NA system, bathrooms do not need to use isolation transformers for shaver outlets, which I understand in common in the UK. I don't think that the British can claim that their bathrooms are safer than the bathrooms in the US, especially with all those electric showers.
Of all the systems, the French standards scare me the most with TT earth systems and time-coordinated RDC's that may open up on a high resistance earth-fault (that is, if your lucky, and the RDC has been tested recently, and the moon is in the proper phase). What am I missing here? Why is this a better system?
I think everyone thinks the system that they grew up with is best. If your system is better or has more desirable features, I'd like to hear you state your case.
Beachcomber
| Three phase power IS widely available in the USA, even in many rural | districts. Just about every PUD in my region, (the Pacific | Northwest), has a special tariff for true three-phase service. | | It's just not available everywhere and unlike continental Europe, the | houses in the rural US are often not clustered together in settlements | and crossroads. US farmhouses are more often found in isolated | areas. Most of these isolated areas are economically served by | single-phase distribution feeders.
Suburban distribution also tends to have a lot of single phase running down a street or even a whole neighborhood ... while the next street or neighborhood gets a different phase. I've seen single phase outages take out selected chunks of large suburban areas. I've also seen a case where it was apparently single phase outage on a D-Y substation leaving 2/3 of the suburbs at half voltage.
| You present an interesting discussion for what the "best" system would | be if all the world had the ability to start over and develop "new" | standards from scratch. | | One such way that the "best" system can be described is by its | simplicity and whether it has been successful from a standpoint of | widespread adoption, safety and economy. | | For example, one might criticize the US-North American system of plugs | and sockets as being less rugged than the British or Euro-Continental | counterparts like the "Shuko" system, for example. | | As far as I can determine, the history of the European system of | multiple incompatible plugs and sockets is simply a big mess. I know | they are trying to standardize things, but holy cow, it's enough to | drive you nuts.
They could adopt one of most of them and have a decent system. But it would be a political problem for one of the EU countries to specifically benefit from that choice. But if it had to be one of them, I would prefer the Shuko.
| Looking at it another way, the US NEMA flat, simple sockets are | inexpensive and aesthetically pleasing. They don't need on-off | switches on them for safety like some of the outlets I've seen in the | UK. The plugs mate snuggly with the socket yet there is seldom the | risk of damaging the outlet if you trip over a flex (cord). The plug | will simply come out of the socket if it yanked hard enough. Also, | you get more of outlets per square inch (or cm) of outlet strip, a | distinct advantage of for those of us whose home offices power needs | runneth over.
The switch adds some safety. It would add more in the US than it would in Germany. OTOH, I think a switch should be optional, not mandatory.
I've seen quite a variation in plug tightness in the US, from ones that just fall right out in a breeze, to one where I broke the receptacle trying to get the plug out (and I have one right now that looks like I'm going to have to kill the power and pull the receptacle when I finally decide to remove the night light I put in it that won't come out and won't finish going in all the way). It's a GFCI one in the bathroom.
| Although the Euro pins can theoretically carry more current then the | flat US blades, the blades are generally safe enough, easy to align, | and allow for an aesthetically pleasing, relatively flat outlet that | can be mounted in a horizontal or vertical position. They also are | 100% backwards compatible in that the 3 - prong outlets accept 2 or 3 | prong plugs. The US-NA system allows for enforcement of hot-neutral | polarity but it is compatible with older or (newer) double-insulated | appliances that don't use it.
The Shuko and some others accept the ungrounded plugs, too.
| Similarly, the widespread adoption of cheap (about $5 each) | outlet-substitute GFCI (ground fault circuit interrupters) has greatly | increased the safety of branch circuits in the US. With this system, | customers don't need to spring for an expensive and potentially | dangerous centrally-located RDC that will kill all or most of all the | power to a residence in the event of a simple fault.
Agreed. That's a big hassle.
|>I'd be happen if the USA were to switch to 480/277 for everything. |>But that'd never happen. |>
| No, even in a climate of rising copper prices, going to | higher-and-higher voltages sounds desirable (theoretically, to a | trained electrical-engineer perhaps), but I don't think the USA would | ever switch to 480/277. Why stop there, how about 830/480? (I could | run my vacuum cleaner with bell wire perhaps? :)
I think the maximum to L-N branch circuits should be no more than 277 volts, and no more than 554 volts L-L. But for service drop to a building dry transformer and special hard wired high power loads not common in homes, I could accept a little higher and maybe 832/480 for that.
| My point is that, at least with 120 volts, your life is less dependant | on the failure of one RDC device. You can still hope for the | downstream GFCI or a short circuit to ground to open up the breaker.
Then go with something lower, like 24 volts.
Remember the system I suggested a while back has:
| If you must take a shock, 120 V. feels a whole lot less intense than | 240 volts and the difference just might be for you to be able to let | go before your heart kicks off.
60 volts feels even less intense. Where to draw the line is in part a matter of opinion.I know the difference between 120 volt shock and 277 volt shock. With the latter one, a few choice words got loose.
But I do believe the electrical safety has advanced to the point where even 480/277 is plenty safe to handle, more so than 400/230 was just a decade or so ago. Most things would be connected to 277 L-N if this were used, not 480 L-L.
| Also note that with the US-NA system, bathrooms do not need to use | isolation transformers for shaver outlets, which I understand in | common in the UK. I don't think that the British can claim that their | bathrooms are safer than the bathrooms in the US, especially with all | those electric showers.
But at 24 volts, a shaver would be even safer, isolation or not, GFCI or not, all other things being equal.
| Of all the systems, the French standards scare me the most with TT | earth systems and time-coordinated RDC's that may open up on a high | resistance earth-fault (that is, if your lucky, and the RDC has been | tested recently, and the moon is in the proper phase). What am I | missing here? Why is this a better system? | | I think everyone thinks the system that they grew up with is best. If | your system is better or has more desirable features, I'd like to hear | you state your case.
There are many aspects of the US/North American system I don't like. The 60 Hz is about the only thing I do like about it. I'd rather go on up to 72 Hz.
All in all, though, if just the snap of fingers would instantly replace the entire North American system with 400/230 at 60 Hz and Shuko plugs, I would do it. Still, I like my 288/24 system design best.
Phil:
You make some interesting suggestions. I'd love to have either 12 or
24 VDC available all over my home so I wouldn't have to deal with all these wall-wart power supplies. Each cord/plug would need an individual fuse or circuit breaker, though. Otherwise there might be some fairly dramatic arcs drawn if these are shorted out.Going too low in voltage is going to be a problem though, at least for some of the huge USA McMansion houses that I have seen recently. The current would be high (for a given needed power level) and the voltage drop could be excessive for some of the long distance runs. No one is going to want to run a toaster or a washing machine at 60 Volts. I can only imagine what the starting current would be on my air conditioner even if heavy duty motors were available at that level.
The trade-off between high voltage and low voltage is always going to be less copper vs. more copper, more insulation vs. less insulation, less safety vs. more safety, etc. The UK ring mains system seems to be one answer to the expensive cost of copper. As I understand it, this was introduced after WWII. In the USA, they revised the code during WWII to use the neutral as as a grounded conductor on dryers and electric ranges, to save a copper wire, but now this is no longer permitted.
If you are speaking of 3-phase systems... and this generally means a wye system on the secondary for distribution... The line-to-line voltage is going to be 1.73 (the sqrt of 3) x the line-to-earth voltage. I'm not sure how you are deriving your proposed 400/230 or
288/24 volt schemes. Perhaps you could explain how you would produce these voltages economically?...3 phase is not always better, BTW.... There are hidden costs beyond just paying a higher tariff to the power company. Earlier you mentioned entire parts of town going to a brownout if a phase is lost. I've experienced this up close and personal.
I lived once lived in a 36 unit condo building served by a 3-phase
120/208 drop with a secondary wye/primary delta transormer. One day one and only one of the primary phase conductors blew a fuse because of a fault at the fire pump. I came home to my lights operating at half voltage and just for fun, measured something like 63 volts on my refrigerator outlet. "That can't be good", I thought.Bottom line, nothing suffered permanent damage in the unit, but the building itself had $12,000 in damage from burned out elevator motors due to single phasing. The power company said "Nooooooo, not our problem...". The building's construction electrician had failed to install low cost "3 phase monitors" on the buildings elevators, claiming that these were "luxury" options not in the original budget.
Beachcomber
| You make some interesting suggestions. I'd love to have either 12 or | 24 VDC available all over my home so I wouldn't have to deal with all | these wall-wart power supplies. Each cord/plug would need an | individual fuse or circuit breaker, though. Otherwise there might be | some fairly dramatic arcs drawn if these are shorted out. | | Going too low in voltage is going to be a problem though, at least for | some of the huge USA McMansion houses that I have seen recently. The | current would be high (for a given needed power level) and the voltage | drop could be excessive for some of the long distance runs. No one | is going to want to run a toaster or a washing machine at 60 Volts. | I can only imagine what the starting current would be on my air | conditioner even if heavy duty motors were available at that level.
Do what they do for low voltage lighting now ... the transformer is near the utilization.
| The trade-off between high voltage and low voltage is always going to | be less copper vs. more copper, more insulation vs. less insulation, | less safety vs. more safety, etc. The UK ring mains system seems to | be one answer to the expensive cost of copper. As I understand it, | this was introduced after WWII. In the USA, they revised the code | during WWII to use the neutral as as a grounded conductor on dryers | and electric ranges, to save a copper wire, but now this is no longer | permitted.
I do not believe that there were 4-wire circuits prior to WWII. But I can beleive that a copper shortage might have delayed introducting the requirement for the 4th wire.
But they could have saved a wire by mandating every part of the dryer work directly with 240 volts. Then they don't need a neutral. Then the ground would be a good thing, but it can be a smaller size.
| If you are speaking of 3-phase systems... and this generally means a | wye system on the secondary for distribution... The line-to-line | voltage is going to be 1.73 (the sqrt of 3) x the line-to-earth | voltage. I'm not sure how you are deriving your proposed 400/230 or | 288/24 volt schemes. Perhaps you could explain how you would produce | these voltages economically?...
Where single phase is all that is available, the transformer secondary would be a split phase (144-0-144) system, where each line is 144 volts relative to the grounded center tap, and 288 volts line to line. Where three phase is used on the LV side, it would be a star/wye secondary with each leg being 166 volts relative to ground, which gets that 288 volts line to line (in addition to 288 volts 3-wire 3-phase).
The 24 volts would be derived with transformers at strategic places. They would be fed with 288 volts into the primary. The secondary can be 24-0 2-wire or 24-0-24 3-wire, but all loads would be 24 volts. There would be no three phase at this level, so it could be made to also supply 48 volts. But it would still be AC. A standard DC system might be a good idea, too.
| 3 phase is not always better, BTW.... There are hidden costs beyond | just paying a higher tariff to the power company. Earlier you | mentioned entire parts of town going to a brownout if a phase is lost. | I've experienced this up close and personal.
I believe that was a lost phase going into a D-Y transformer feeding that end of town. It sure looked like it.
| I lived once lived in a 36 unit condo building served by a 3-phase | 120/208 drop with a secondary wye/primary delta transormer. One day | one and only one of the primary phase conductors blew a fuse because | of a fault at the fire pump. I came home to my lights operating at | half voltage and just for fun, measured something like 63 volts on my | refrigerator outlet. "That can't be good", I thought. | | Bottom line, nothing suffered permanent damage in the unit, but the | building itself had $12,000 in damage from burned out elevator motors | due to single phasing. The power company said "Nooooooo, not our | problem...". The building's construction electrician had failed to | install low cost "3 phase monitors" on the buildings elevators, | claiming that these were "luxury" options not in the original budget.
It is the power customer's responsibility to deal with single phasing.
Note that when a primary phase is lost on a D-Y, not only do you get a lower voltage on the 2 phases that are now being fed to the 2 windings in series that would have been pulled out by the dead phase, but they are also different in phase angles. Suppose phase B is the lost one coming into a delta primary. That means A-C is full voltage, but A-B and B-C are each splitting the remaining voltage from A-C. On the secondary side, the AC leg is normal (120 volts) while the AB and BC legs are not (60 volts). But the AB and BC legs also at the same phase angle. Line to line connections wil be more telling: AC-AB and AC-BC would be 180 volts instead of 208 volts. But AB-BC will be zero because those legs are the same phase. Cascade 3 contactors of 3 poles each. Each one has a 208 volt coil powered by a different L-L leg. At least one of them will drop open when single phasing happens. It's not that hard to do. There could even be simpler solutions.
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