Which Residential Voltage & Frequency Arrangement Is Best?

400hz 100V

Generally, higher voltage is good, because it carries a lower current for the given power. Of course, higher voltage also increases the possiblity of arcing (IIRC, I was a mechanic, not an electrician), so a balance needs to be struck. I say go with 450V.

You're posting from google. If you do a google search first, you'll find this has already been done to death, many times over.

Good night.

As regards voltage 230 ever time. Permits effective high powered small appliances, kettles etc.

The Americans wire 110-0-110 (=220) into fixed appliances such as stoves and aircon.

110v has no electrical shock safety advantage over 220/230v. If it would not be safe at 220v, it could not be relied on to be safe at 110v.

The 230v standard does have significantly lower fire risk, (half the current for the same power).

A typical American wooden built house with aluminium wiring and 110 volts = "Giant Firework"

As regards frequency there's not much in it. Iron losses in transformers increase with frequency., but fluorescent Tubes flicker less at 60Hz (however increasingly nowadays fluorescent tube ballast are high frequency solid state devices, so this wouldn't then count).

Similarly TV's scanning at 60Hz, but AFAIK since colour they are not mains locked any more, but they probably don't move that far away from the local mains freq. to avoid mains intereference running through the picture. Refreshing the pictures at 60Hz uses 20% more bandwidth than

50Hz, hence the American 525 line standard and our 625lines.

DG

The North American system has the advantage that both 120 and 240 volt circuits are available for both fixed and portable appliances. One sees the 240 volt outlets mostly in workshops, farms (for heavy duty electric heaters, or for commecial installations (restaurant applicances, for example). 240 volt circuits are common for air conditioners, dryers, electric ovens, and water well pumps and heavy-duty power tools.

Some Brits are fond of saying that, with our system, we who live in North America can't operate that power hungry deep fat fryer in our kitchens with our wimpy 120 volt appliance circuits. The truth is we seldom miss it. A deluxe kitchen can easily be constructed with a 240 V. outlet for commerical kitchen appliances, if desired.

All American kitchens are required to have at least two 20A 120 volt appliance circuits for a total of (at least) 4800 watts available. These seems to do a good job powering the toasters, microwave ovens, mixers, can openers, and electric grills that are commonly used. Also, when the design calls for more power, an additional circuit is installed

Probably the biggest safety advantage of the North American system is that in no room of any house is there a conductor with greater than

125 volts potential to earth ground (even though 240 volts is available where required). This applies to kitchens, bedrooms, bathrooms, hot tubs, garages...everywhere.

In theory yes... but if you've actually been the recipient of a shock at 220 - 230 volt, it is comparatively more painful, (and more difficult to let go of) than 110-120 v.

If what you are saying were true, there would be no need for the 50 -

0 - 50 volt scheme that is used for UK power tools on construction sites. ... If there are 240 V. appliances... why not 240 V. power tools? There is a reason for this.

In contrast, modern 120 v. power tools are considered electrically safe in North America. (This was not always the case before universal grounding, double insulation, and the requirement for GFCI (differential) circuit protectors).

There is a tradeoff between voltage and current. The downside of the higher voltage is that insulation requirements are higher and the physical spacing between two conductors at devices such as a plug must be greater (hence the device must be physically larger).

I like the design of the Shuko plug and receptacle. It seems safe and is well designed for a 230 volt circuit. It's just not very elegant when you put them in a power strip, for example. The whole thing is just too big.

Also, speaking of fire risk... Because of the comparative difficulty of making low wattage incandescent light filaments at 240 volts, these lamps tend to run a super hot temperatures (when compared to equivalent 120 volt incandescent lamps with a similar light output).

I'm sure that the UK is well on its way to converting to compact fluorescents, but I'm also sure that many of these super hot incandescents are still in use.

Aluminum (same element -different spelling) wire for US residential branch ciruits has not been used for decades. It was recognized as a problem and there have have been wiring techniques developed to make retrofit installations safer.

Aluminum and Aluminum alloys are commonly used for service entrance cable and are even considered to be safer than copper. In the event of a rare, direct short, the aluminum cable will eventually melt and break the current. The copper is likely to get insanely hot, but keep the current flowing for a much longer time- so I'm told.

50 Hz flicker is visible in low wattage incandescent bulbs. The filament just cools too fast. This is one of the reasons the higher 60 Hz frequency was chosen for the North American System.

TV's require precisely locked oscillators, which were difficult to design and stablize in the 1940's and 1950's, hence, the TV's of the time were locked to the local line frequency. This represented the most accurate time base of the time.

Oscillators got better and more stable with the introduction of solid state circuits and crystals. No modern TV need to use the power line for an external time base reference.

Beachcomber

The Germans wire 3-phase into heavy appliances - like instant showers in bathrooms.

The British system has the advantage that we don't need separate circuits.

Yes, but you still can't use a decent kettle in the bedroom.

Yes, it's because 50V has a safety advantage over both 110 and 240V. 50V is *Extra* low voltage. Anyway, 50-0-50V pre-dates RCDs and isn't actually necessary now, although most sites still insist on it.

A lot of things are considered safe in North America that aren't here, like wire nuts and sockets in bathrooms.

Owain

48v 0Hz (DC)

Since just about everything uses SMPS theses days - even lights - why have AC at all - and 48v is pretty much safer, especially DC.

The consumer unity has a 200A bridge rectifier and a bank of capacitors in it, and a power factor correction inductor. :D

No nasty interference either.

AL wiring inside homes has not been around since the late 1970's. Better dust off your "way back machine"

Please provide documentation for "230v standard does have significantly lower fire risk".

In message , SQLit writes

It's all to do with currants raisin the heat

The presence of 2 voltages is a disadvantage, because it restricts what can be plugged in where, and increases the amount of wiring required. Everything on 240 makes better sense. We used to have a 4 plug system, with 2A 5A and 15A 3 pin plugs, plus 5A 2 pins. What a horror it was: a single universal socket is a significant advantage.

all ours have 3kW outlets, theyre universal, no extra cost.

I'm surprised, I though you were a real power hungry nation. We have at least one 30A 240v circuit in every kitchen, 7.2kW.

IRL its not a safety advantage. People think they can get away with things they wouldnt dare do here, and the result is more deaths, not less. Our system is specced to (mostly) higher safety standards partly because it needs to be. 240 is not to be messed with, and everyone knows it.

yes, hence the differing attitudes towards it. The US routinely does various things with electrics that are illegal here on safety grounds.

There is no need for 55-0-55 onsite, we do use 240v tools onsite. 110v tools are a historic thing. With RCDs we no longer worry about using

240v on a wet site so much, whereas before RCDs, in wet conditions, it was a clear risk - as of course 110 would be, though less. Hence we went with 55v.

I'm not sure thats a downside, really it depends on your material resources as to what voltage cable is most economical. IIUC America has a lot more copper availability than here, so we spend more on the plastic and less on the copper. Fwiw a century ago copper cable was considered excessively expensive, and steel cable was sometimes used. Steel makes truly bad cable, illustrating the high cost of copper.

larger spacing is needed, but its not a downside in any way.

no, not at all. The spacings involved are small compared with plugtop sizes, it really makes no difference to plug size. Our huge plugs are a British oddity I would definitely not repeat if starting from scratch.

IEC plugs/sockets might be good if they were metal sleeved, using the sleeve to connect earth.

Our plugs seem to be an oddity of history. At least theyre a bit better than the South African plug, which is the one we quit using half a century ago. But the US ones are very poorly specced, a recipe for trouble.

I'd like to see a 2 pin version of our square pin plugs. Compatible, cheap, space saving, material and energy saving.

no no. Higher R requirement means a thinner filament, and this is run at lower temp to slow down evaporation, as there isnt much to evaporate. The filament runs cooler: this has insignificant bearing on the temperature of the glass bulb. This is only an issue for 25w and

15w bulbs, the higher wattage ones perform better. 110v is closer to the ideal efficacy voltage for house bulbs. But of course there are better solutions.

In a short a fuse would blow. If it ever gets to the stage where the incoming cable melts, the system design has failed badly, and was a duff design. IRL this isnt a significant failure mode.

Ali expands and contracts, loosening connections. Then when its not gas tight it oxidises. The resulting resistance produces heat and more oxidation... your ali supplies are not an advantage. We still have incomers that are near a century old, with PBJ etc insulation.

The real difference with frequency is the enormous tonnage of iron used in transformers, ballasts and motors. 60Hz is definitely better than

50, and 100 better again. Theres a tradeoff because higher frequencies reduce the maximum service area, which causes problems for the power cos. Also very much higher f and laminated transformers would become too lossy. Increasing f, upto a point, would reduce the size and losses of transformers, motors, and ballasts.

IIUC the US got 525 lines in the 50s, we got 625 in the 60s, as much down to technical progress as anything. Same with the colour system, PAL is much better than NTSC, because we waited longer before implementing colour.

I think this is a myth. The main oscs in a tv are line and frame. (There are also rf, psu and colour oscs.) Line oscs have always been synched to the received signal, first by hard locked sync, later by flywheel sync. Frame scans have always been locked to received signal too. Initially the last line on the frame was 1.5 lines long, and the field scan locked to this. This was changed to work with the much better flywheel system, all lines became the same length, the frame osc had to lock to the differing sync pulses.

The reason to keep frame rate and mains freq locked _at the tx end_ is to avoid noticing the frequency difference ripple moving the picture about, which is liable to happen on old kit, and looks rather bad. A fixed distortion OTOH is hardly noticeable, especially on early sets that were inherently much more geometrically distorted than modern flatter CRTs. There has never been power line lock at the receiving end, not with 405 or 625 lines. Perhaps it got implemented on the earlier 30 line mechanical system, whch was otherwise syncless.

NT

You said later in your post and I quote "110v is closer to the ideal efficacy voltage for house bulbs" so that is at least one reason for having the lower voltage. Not all the world has gone over to compact fluorescents and there are some applications where they might be downright undesirable.

I have already argued that safety is another reason.

The North American Codes specify that no point on the kitchen counter should be less than 3 ft. from an outlet. In my small modest 15 x 15 kitchen I count no less than 9 duplex outlets (18 outlets total). Our codes are concerned with safety, not convenience, but in this case, the idea is not to be plugging toasters and other high current appliance into extension cords. You can't even buy a toaster in the US anymore with a cord longer than 3 feet. Ever see those movies from the thirties were the appliances were plugged into the pendant socket hanging from the ceiling? Apparently, that was real bad...

We are not necessarily power hungry, but there are lots of appliances that may not necessarily be in use at the same time in a modern kitchen. The requirement for at least two 20A circuits and the requirement for many outlets serve the need.

I will conceed that those ring main circuits do allow you to power that 7.2 kW deep fryer though.... Something we can't do without extra effort.

The most bizarre Euro power setup I ever saw was in the apartment I rented in Paris about 10 years ago. That French "Disjouncter" or whatever they call it would ration the power to the point where I could not have my water heater working if certain other routine loads where online at the same time. This was true even though the total load was much less than the installed capacity. They just didn't want you to be using too much power.

It reminded me of the episode of the American TV Series Green Acres called "You can't plug in a 6 with a 2". Farmer Douglas tried to explain to his wife Lisa that all the power cords for the kitchen appliances had numbers on them corresponding to the size and current consumption of the device. If you went over 7, the generator outside the farm would start on fire.

I stand by my original statement. We don't have many people in the US that say, "Gee it's only 120 volts... I don't respect it". Some... but not many.

120 volts is safer than 220V. just as 220V is safer than 480V.

The same could be said for some of the UK practices from what I've read.

Whether it's 120V or 240V, the N.A. codes say that we don't put these voltages in the shower. We don't even go near 240 volts in the bathroom. Other than lighting and a bathroom heater, there is only one allowed a GFCI protected outlet by the sink for a shaver or hair dryer. Some homes have electric outlets by the toilet. That is if you have one of those fancy TOTO models that sprays warm water up your arse.

Beachcomber

And how do you get 400Hz to a home or industry? It is inferior to either 50 or 60 Hz for transmission and distribution. It does have advantages in aircraft but that 's about it. As to 100V- worsens the situation.

I hope that you are not serious.:)--

Don Kelly @shawcross.ca remove the X to answer

------------------------------ You must be kidding!

Don Kelly @shawcross.ca remove the X to answer

Soirta, but actually, inside a house, its about ideal.,

Useless for transmission tho. Stick to 50Hz there. Or HVDC and inverters...

And with whole house RCD protection the UK 230 volt system is no worse at all....

Odd that steel cored ally cable is use on the national grid at

400 kV!.....

I think the 'mains' in some modern helicopters is about a 270Vdc bus, generated by one central 3-phase rectifier on the 200V L-L AC. Saves a sigificant amount of weight in both the generation and consumers. I have no idea how they switch 270Vdc though.

MOSFETS are able to go that high..450V MOSFETS are made in vast quantities for mains voltage SMPS.

In article , Tony Williams writes

Wonder why such a high voltage, its not that transmission losses will be all that great ?....