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Why does the world harbor so many different voltages, plugs, and sockets?

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Re: Why does the world harbor so many different voltages, plugs, and sockets?

#31

Post by NoOneNew »

varispeed wrote: post #13
gumby wrote: post #9

Unfortunately this doesn’t get to why. For example the absurdly large UK plugs with integral fuses date to first (or was it postwar? I forget) surge of electrification which,for expediency’s sake was often point-to-point (like “party line” phones) so local devices needed protection. Nobody else went this route (well, excepting some dodgy informal systems I’ve seen in India and southern Africa) so could get away with…

I am always getting anxious that I get electrocuted when I disconnect US plug. I wish the whole world adopted UK plugs and sockets for safety.

Dont touch the prongs???

34 years in the US. I have never been electrocuted when plugging/unplugging anything. I dont know anyone that has been.

Wtf are you playing at? Everywhere across the planet has to adopt things that make you comfortable because you apparently dont know how to not touch the metal bits when unplugging something? Wait no, you're the one they write, "Dont eat package" for, aren't you?

Re: Why does the world harbor so many different voltages, plugs, and sockets?

#32

Post by Scoundreller »

tzs wrote: post #20

The article seems to be mostly about voltages and plugs/sockets that the consumer will see at the outlets throughout their home. It's interesting to look a little beyond that. Most of the places that offer 230 V at their outlets seem to be distributing power in the neighborhoods using a 3 phase 230 V system. Individual houses are wired to one phase of that. In the US, distribution throughout a neighborhood is typical…

> There is a 240 V center tapped step down transformer for each house.

Maybe in rural areas, but in (sub)urban areas, you'll have a... ?node? step-down transformer serving many homes.

> The normal outlets in the house are wired across half the transformer, giving 120 V

Would add that homes usually balance this, so half of 120V circuits will be wired to one phase, and half to the other. So sometimes you get power failures where half the house loses power. Also means installing power-line networking may only work (well) when they're on the same half of circuits of the house, unless you add a capacitor between the two sides to bridge the gap for high frequencies. Or turn on a 240V appliance to bridge the two sides together.

Re: Why does the world harbor so many different voltages, plugs, and sockets?

#33

Post by masklinn »

tzs wrote: post #20

The article seems to be mostly about voltages and plugs/sockets that the consumer will see at the outlets throughout their home. It's interesting to look a little beyond that. Most of the places that offer 230 V at their outlets seem to be distributing power in the neighborhoods using a 3 phase 230 V system. Individual houses are wired to one phase of that. In the US, distribution throughout a neighborhood is typical…

> Individual houses are wired to one phase of that.

In many countries houses get wired to all three phases and the phases get split up afterwards, sometimes with a few 3-phase plugs available for high-power applications.

Re: Why does the world harbor so many different voltages, plugs, and sockets?

#34

Post by lazide »

palijer wrote: post #26
varispeed wrote: post #13

Earlier quoted context omitted.

I am always getting anxious that I get electrocuted when I disconnect US plug. I wish the whole world adopted UK plugs and sockets for safety.

Install some GFCI outlets everywhere and the risk is gone. Also you are very, very, very unlikely to be electrocuted in this way even if you do touch the metal and get voltage passed through you. Like, it is possible, if one finger in a hand is touching the live prong, and another finger on the other hand is touching the neutral/ground prong, you'd pass current across your chest. Or if you are touching something that…

It might REALLY REALLY hurt though.

Still harder to do than it looks, and to your point, very difficult to actually die from. Not impossible, but very unlikely.

Re: Why does the world harbor so many different voltages, plugs, and sockets?

#35

Post by ahartmetz »

Scoundreller wrote: post #21
helsinkiandrew wrote: post #3

Go just about anywhere in the world and you can charge your laptop with a simple adapter - yet take a USB cable and and it's anybody's guess whether it will work - even if you can physically plug it in.

Recently learned this the hard way. A Macbook will charge over any voltage over USB-C. Slowly, or maybe just increasing battery life, but it'll take anything. It'll charge from a 5V1A power bank if you like. So when I had to make an emergency trip, I assumed my newish Dell with USB-C charging would be the same. And that assumption was false. Unless you're charging with 20V USB-C (not common outside of laptop chargers…

FWIW, the Thinkpad T14 Gen1 also accepts any USB voltage (or at least 5V and 20V) for charging. I did some experiments with phone chargers.

Re: Why does the world harbor so many different voltages, plugs, and sockets?

#36

Post by edrxty »

Scoundreller wrote: post #21
helsinkiandrew wrote: post #3

Go just about anywhere in the world and you can charge your laptop with a simple adapter - yet take a USB cable and and it's anybody's guess whether it will work - even if you can physically plug it in.

Recently learned this the hard way. A Macbook will charge over any voltage over USB-C. Slowly, or maybe just increasing battery life, but it'll take anything. It'll charge from a 5V1A power bank if you like. So when I had to make an emergency trip, I assumed my newish Dell with USB-C charging would be the same. And that assumption was false. Unless you're charging with 20V USB-C (not common outside of laptop chargers…

USB C is a nightmare. Everyone has basically decided that following the spec isn't worth it and there's shit everywhere. The connector is terrible for laptops, I have to be incredibly careful not to bend the connector and the cables wear out surprisingly quickly from connect/disconnect cycles.

Re: Why does the world harbor so many different voltages, plugs, and sockets?

#37

Post by nwallin »

tzs wrote: post #20

The article seems to be mostly about voltages and plugs/sockets that the consumer will see at the outlets throughout their home. It's interesting to look a little beyond that. Most of the places that offer 230 V at their outlets seem to be distributing power in the neighborhoods using a 3 phase 230 V system. Individual houses are wired to one phase of that. In the US, distribution throughout a neighborhood is typical…

It's also common in the US for neighborhoods to have 240V 3 phase, and for a neighborhood to have a common neutral. Each house gets the neutral and 2 of the hots. Hot to neutral gives 120V, hot to hot gives 208V. (240*sin(120 degrees))

The result is that the high voltage appliances need to support both 240V and 208V. Most appliances just design for 240V and test to ensure they don't break at 208V, and just give reduced power at 208V. Which is often fine, but a 208V stovetop is a pretty miserable experience.

Re: Why does the world harbor so many different voltages, plugs, and sockets?

#39

Post by masklinn »

gumby wrote: post #9

Unfortunately this doesn’t get to why. For example the absurdly large UK plugs with integral fuses date to first (or was it postwar? I forget) surge of electrification which,for expediency’s sake was often point-to-point (like “party line” phones) so local devices needed protection. Nobody else went this route (well, excepting some dodgy informal systems I’ve seen in India and southern Africa) so could get away with…

> For example the absurdly large UK plugs with integral fuses date to first (or was it postwar? I forget) surge of electrification which,for expediency’s sake was often point-to-point (like “party line” phones) so local devices needed protection.

It was during WWII, and it was less expediency and more efficiency and saving on copper. Ring circuit can deliver more power to more surface with less copper.

The UK used to use standard radial topologies before WWII, this is also allowed by modern building code, and very high power devices (>3kW) generally have their own "radial" circuit.

Re: Why does the world harbor so many different voltages, plugs, and sockets?

#40

Post by jaclaz »

fy20 wrote: post #24

Italian sockets are a fun one. The plugs come in a 10A and 16A versions which are slightly different sizes. Newer sockets will usually take both plugs, but older sockets take one or the other. The size looks very similar to European Schuko sockets, and if you jam it in, then it will just about fit (without an earth). You can get adapters all over the place, which is the way you are supposed to do it, but for older so…

Yes and no.

Meaning that nowadays three ways sockets ( Schucko/10 A/16 A) are common enough, but a Schuko (or a three way one) will take two "modules" whilst both the 10 A and the 16 A are narrower and take a single "module". (typically electric boxes in the wall are either a model 503 - three modules - or a 504 - four modules, but these latter oness can only be found in more recent houses), so until the use of 504's became more common, historicallty Schuko's were rare, as it was not possible to have in the same box a bipolar switch+fuse+Schuko (while it was possible to have bipolar switch+fuse+16A) which is/was the proper setup for high power sockets and with a single socket installed, it resulted in looking asymmetrical, see:

https://www.elettronew.com/blog/2017/05/11/presa-elettrica-t...

JFYI, recently came out a new kind of socket (not yet very common) that allows in two modules to insert either a Schuko or two 10 A (or 2x16 A or 1x10A and 1x16A):

https://www.archiproducts.com/newsletter/dossier/193843

The 10A one is actually compatible with the class 2 (earthless) Europlugs:

https://en.wikipedia.org/wiki/Europlug

Schuko's have larger pins, and it is not a good idea to jam them in a normal Italian 10A plug as the plastic cover of the plug might crack.

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