USA domestic power supplies

High(er) voltage causes more current to flow, so will trip a protective device more quickly in the event of a fault.

Owain

Define "better". Less chance of a shock, but wooden houses, aluminium cables,

Yes, or is that what you meant?

for the same wattage, higher voltage means LOWER current.

In article , Dave Plowman (News) writes

Not statutory but by the weight of cable that an individual can drag around.

Talking about faults here, not normal service. The fault will have a certain resistance, not consume a certain amount of power. So higher voltage means higher current.

That's right. 240 V circuits (with a +120, -120, & ground) are run for clothes dryers, water heaters, & cookers. (I can't remember which of those need a neutral as well --- it might vary between specific models of appliance.) There are special plugs & sockets for these, so you can just plug a replacement electric cooker in, instead of needing to mess with a terminal block.

I was more thinking of the limit of the normal US 120v outlet.

Several times I've taken delivery of US kit, still with the mains plugs on. Jeez, the quality of some of those is awful. I've not seen such crappy plugging since we got shot of the last of our 5A and 15A arrangements, and even then, the vast majority of our stuff was much, much better, 50 years ago.

Thanks to everyone who has contributed to this question.

I have found this comprehensive link

and this description - both of which help to explain my confusion.

There is no universal standard here unfortunately. The US electrical grid is composed of a lot of smaller grids that were connected together, but each individual power utility may or may not have the same voltage standards as their neighbor. Even within a utility's service area, there are new services and old services (called "legacy") that cannot change until the connected users are demolished. The only thing that is now relatively universal is that we are all 60Hz (with the exception of a few islands of 25Hz still in use). So here are all of the 3 phase low voltage "standards" I am aware of:

208V Delta (3 wire); rare legacy

120/240V Delta with a center tap between A and C phases for 120V (4 wire "stinger leg"); still provided for small commercial users with >10% 120V

440V Delta (3 wire); legacy

277Y480V (4 wire); new standard for industrial service

Bob

Walk down the electricl isle at Home Depot, and it's like going back to what we used to use over 80 years ago.

Some years ago, I was at a conference in New York and spoke with one of the electrical accessory manufacturers there, which also makes stuff for the UK, and asked them why the quality of US electrical kit is so poor, and it's years behind. He smiled - not the first time he'd been asked this, and he had the answer instantly. No one will spend $1 on a (US) socket outlet, because there's a bin full of them for 50c, and people will only buy the cheapest. In the UK, the bulk of the market is not owned by the cheapest product; innovation and safety sell well, and indeed there's been fierce competition ever since 1930's between manufacturers to produce increasingly safer products, easier to install in unskilled hands, remain safe even when misused, etc. In the last 80 years, we've redesigned our mains plugs and sockets twice, making them increasingly safer each time. Most other countries are still running on 100+ year old designs, which they have just tinkered with.

They probably still sell scruits!

Thanks for confirming yet again you know nothing about electrics.

For that to make any sense in context, it would have to be that NZ uses exactly the same setup as the US.

So thanks for confirming yet again you know nothing about electrics.

I don't know why you bother offering thanks to what is simply a trolling "Information Vacuum" (all his posts suck, big time).

Woddles has obviously never been to the US of A.

Worst thing I ever saw there was a device like a power strip, about 8" or so long. It plugged into the mains and had two long slits in it, separated by the same amount as the flat pins in their 2-pin plugs. This meant that you could plug in as many 2-pin plugs as there was physical space for, probably as many as 20 or so. The one I saw had 7 or 8 plugs in it, still room for plenty more, and even then it was running hot.

Do (new) Australian and NZ plugs not require sleeved L&N pins from

Martin.

Are you saying they have always been three pin?

Could you please clarify this. You are stating that all sockets were 3 pin in the mid 1930s?