This article only scratches the surface. There are at least 241 NEMA (National Electrical Manufacturers Association) configurations in the USA. Each serves a purpose. Each voltage/amperage combo gets one in straight blade and locking. This prevents people from plugging into something dangerous. Also, there is support for obsolete stuff, such as two-wire.
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?
#12I know it’s likely highly subjective and prone to local bias, but I feel a next step would be to do user testing of alternatives and derive a best form factor plug. What’s the best plug we could all be aspiring to. Some are clearly more usable than others.
One metric: easy of use in the dark/based on feel alone.
Re: Why does the world harbor so many different voltages, plugs, and sockets?
#13Unfortunately 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.
Re: Why does the world harbor so many different voltages, plugs, and sockets?
#14Unfortunately 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.
Then surely shuko plug is the ultimate of both worlds? There is no need for the increased size and complexity with the internal fuse, and the socket is recessed so you can't touch the pins until they are way out to the connection points.
Re: Why does the world harbor so many different voltages, plugs, and sockets?
#15Unfortunately 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.
I wouldn’t worry too much. The voltage is low. More importantly, the three prong (grounded) plugs have longer ground pins than the other pins, so the most electrically convenient return path will always be connected while any current is present.
You can’t see this structure in the standard diagrams such as the ones in the article but you can tell it for yourself by inspection.
Re: Why does the world harbor so many different voltages, plugs, and sockets?
#16Earlier 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.
Then surely shuko plug is the ultimate of both worlds? There is no need for the increased size and complexity with the internal fuse, and the socket is recessed so you can't touch the pins until they are way out to the connection points.
Yes, the Schuko is a good design. Probably the best, although it’s a bit inconveniently large for my tastes.
The modern US one (NEC) is probably the best trade off of size and safety (see my parallel comment on its physical design). Though I do think there is still too much use of two-prong plugs, despite the near ubiquity of grounded sockets these days.
Re: Why does the world harbor so many different voltages, plugs, and sockets?
#17Unfortunately 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.
UK plugs seem way overengineered. European schuko plugs have all the same advantages without weighing a ton.
Re: Why does the world harbor so many different voltages, plugs, and sockets?
#18Earlier 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.
I wouldn’t worry too much. The voltage is low. More importantly, the three prong (grounded) plugs have longer ground pins than the other pins, so the most electrically convenient return path will always be connected while any current is present. You can’t see this structure in the standard diagrams such as the ones in the article but you can tell it for yourself by inspection.
... when there are 3-pins. Not every device has this. I haven't done a survey, but less than 50%, including this $1000+ computer's charger.
Re: Why does the world harbor so many different voltages, plugs, and sockets?
#19I know it’s likely highly subjective and prone to local bias, but I feel a next step would be to do user testing of alternatives and derive a best form factor plug. What’s the best plug we could all be aspiring to. Some are clearly more usable than others. One metric: easy of use in the dark/based on feel alone.
[deleted]
Re: Why does the world harbor so many different voltages, plugs, and sockets?
#20The 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 typically 15 kV. There is a 240 V center tapped step down transformer for each house. The normal outlets in the house are wired across half the transformer, giving 120 V. Ovens, water heaters, dryers, EV chargers, air conditioners, etc get wired across the full transformer giving 240 V.
There was an interesting comparison of the two approaches in this Quora answer that turned up in my Quora digest mailing two days ago [1]. (Not sure if the link will work without a Quora account).