To be quite honest, Edison was the salesman of his day. He was clever, but he was very good at packaging and marketing. In modern times, someone like Musk for example, has a lot of echos of Edison's showmanship.
DC was extremely impractical for distribution. You could not transform the voltage up/down without motor-generator sets, which are inefficient, bulky and noisy. You also have a lot of issues around the types of arcs it generates in switches / at sockets (which limit the voltage) and with galvanic issues where it can pull ions of metal from point to point and either strip a contact surface, or electroplate it.
DC is also quite cumbersome for electric motors, whereas AC can drive them directly. Although, it was easier for big traction motors on trains as you could use variation voltage to control speed.
In the US context, everything happened around Edison and he was the big noise in power. In Europe, there were others, and notably big companies like Siemens, but there was no single system or philosophy for doing things certainly until after WWII and the beginning of pan-European standards for some of these things.
For example, the Depford Power Station in London, which was driven by Sebastian de Ferranti's ideas, generated AC back in 1888 at 88 1/3 Hz
There were environmental objections to large scale power infrastructure or motor-generator sets in London as they were noisy in the case of the converters or smelly in the case of small coal burning plants, so it was one of the first cities in the world to develop a HV power grid, distributing at 11kV 88 1/3 Hz with domestic / residential and commercial customers being provided with AC single phase connections.
AC was also being used in Paris around 1878 - There were AC power systems installed at a Paris Expo mostly for public lighting.
This allowed a big plant to be located out of town, thus solved a lot of annoyance with the prospect of ugly infrastructure close to central London.
Other cities adopted other systems, including Edison-style DC, but there were a number of standards that were all in existence simultaneously.
Some places adopted 3-wire 127V / 220V systems which would be quite comparable to the present day US system. Some adopted DC systems and others adopted systems like 200V 50Hz, 210V 50Hz and ultimately 220V 50Hz.
Here in Ireland the power system was nationalised in 1927, with the local power companies being gradually bought up by ESB, standardised and linked to the grid and they picked 220V (380V 3-phase) 50Hz. (There had also been 200 and 210V 50Hz systems in use too.)
50Hz seems to have just been a convenient standard as it allowed a balance between flicker free incandescent bulbs and not having to run the generators at very high RPM. It's also 100 peaks / troughs per second, which fits with the logic of metric base-100.
60Hz came about for exactly the same reasons, but was just landed upon possibly because of it being 60 cycles, 60 seconds in a minute, 60 minutes in an hour etc.
They're quite arbitrary.
A lot of older European fittings and fixtures are still rated for AC/DC. So, you'll typically see 16Amp / 10 Amp DC because there's a difference in safe current carrying and arcing characteristics.
The reason for the switch on UK sockets was also to do with DC arcs on 200V systems. There was a preference for switching off the power before removing the plug, to prevent arcing and thus avoid damage to pins / contact surfaces etc. There were even types that had a pin with a groove that was locked in place when the switch was on, and only removable when the power was switched off.
But there were umpteen different companies working in competition and harmonised standards only really emerged for all sorts of things in the 1940s. Everything was developed commercially and there were competing designs of plugs, sockets, bulb holders, wiring systems, voltages and frequencies. There's a lot of discussion that seems to talk about 'a European' approach vs 'an American' approach but in reality there were just multiple companies all doing their own thing.
The market ultimately needed standards, as otherwise appliances were very very complicated to produce. So, they emerged and were formalised and ultimately legislated for.
There's also a discussion that seems to assume Europe moved from 110-120V to 220/230V. That's also not exactly true. 220V 50Hz was always used in some areas, and was introduced in others in the 1940s/50s. So, it very much depends on where you are.
The basically reality of it is that 220V (now 230V) 50Hz ultimately won the standards wars in Europe and for the most part so did Schuko plugs/sockets, with a few outliers (including here).
Westinghouse first began experimenting with AC power in the US using already developed technology. He imported a number of Gaulard-Gibbs transformers, which had been developed by Lucien Gaulard (France) and John Dixon-Gibbs (England) and a large Siemens AC generator. His AC systems basically sprung from there.
The downside to AC in the 50-60Hz range anyway, is the cycling can trigger muscle contractions which can cause your hand to grab a conductor and can cause atrial fibrillation.
DC causes far worse burns and tissue damage though as the current flows through continuously and it can also cause weird effects like electrolysis.
Both of them are pretty nasty at high current/voltage, but I wouldn't really give DC Edison's marketing safety approval.
The 230V 50Hz system is pretty rock solid and extremely safe, once you use it with the correct equipment and fixtures and fittings have evolved to become safer and safer over the decades.
[this post was last edited: 10/7/2021-11:09]
DC was extremely impractical for distribution. You could not transform the voltage up/down without motor-generator sets, which are inefficient, bulky and noisy. You also have a lot of issues around the types of arcs it generates in switches / at sockets (which limit the voltage) and with galvanic issues where it can pull ions of metal from point to point and either strip a contact surface, or electroplate it.
DC is also quite cumbersome for electric motors, whereas AC can drive them directly. Although, it was easier for big traction motors on trains as you could use variation voltage to control speed.
In the US context, everything happened around Edison and he was the big noise in power. In Europe, there were others, and notably big companies like Siemens, but there was no single system or philosophy for doing things certainly until after WWII and the beginning of pan-European standards for some of these things.
For example, the Depford Power Station in London, which was driven by Sebastian de Ferranti's ideas, generated AC back in 1888 at 88 1/3 Hz
There were environmental objections to large scale power infrastructure or motor-generator sets in London as they were noisy in the case of the converters or smelly in the case of small coal burning plants, so it was one of the first cities in the world to develop a HV power grid, distributing at 11kV 88 1/3 Hz with domestic / residential and commercial customers being provided with AC single phase connections.
AC was also being used in Paris around 1878 - There were AC power systems installed at a Paris Expo mostly for public lighting.
This allowed a big plant to be located out of town, thus solved a lot of annoyance with the prospect of ugly infrastructure close to central London.
Other cities adopted other systems, including Edison-style DC, but there were a number of standards that were all in existence simultaneously.
Some places adopted 3-wire 127V / 220V systems which would be quite comparable to the present day US system. Some adopted DC systems and others adopted systems like 200V 50Hz, 210V 50Hz and ultimately 220V 50Hz.
Here in Ireland the power system was nationalised in 1927, with the local power companies being gradually bought up by ESB, standardised and linked to the grid and they picked 220V (380V 3-phase) 50Hz. (There had also been 200 and 210V 50Hz systems in use too.)
50Hz seems to have just been a convenient standard as it allowed a balance between flicker free incandescent bulbs and not having to run the generators at very high RPM. It's also 100 peaks / troughs per second, which fits with the logic of metric base-100.
60Hz came about for exactly the same reasons, but was just landed upon possibly because of it being 60 cycles, 60 seconds in a minute, 60 minutes in an hour etc.
They're quite arbitrary.
A lot of older European fittings and fixtures are still rated for AC/DC. So, you'll typically see 16Amp / 10 Amp DC because there's a difference in safe current carrying and arcing characteristics.
The reason for the switch on UK sockets was also to do with DC arcs on 200V systems. There was a preference for switching off the power before removing the plug, to prevent arcing and thus avoid damage to pins / contact surfaces etc. There were even types that had a pin with a groove that was locked in place when the switch was on, and only removable when the power was switched off.
But there were umpteen different companies working in competition and harmonised standards only really emerged for all sorts of things in the 1940s. Everything was developed commercially and there were competing designs of plugs, sockets, bulb holders, wiring systems, voltages and frequencies. There's a lot of discussion that seems to talk about 'a European' approach vs 'an American' approach but in reality there were just multiple companies all doing their own thing.
The market ultimately needed standards, as otherwise appliances were very very complicated to produce. So, they emerged and were formalised and ultimately legislated for.
There's also a discussion that seems to assume Europe moved from 110-120V to 220/230V. That's also not exactly true. 220V 50Hz was always used in some areas, and was introduced in others in the 1940s/50s. So, it very much depends on where you are.
The basically reality of it is that 220V (now 230V) 50Hz ultimately won the standards wars in Europe and for the most part so did Schuko plugs/sockets, with a few outliers (including here).
Westinghouse first began experimenting with AC power in the US using already developed technology. He imported a number of Gaulard-Gibbs transformers, which had been developed by Lucien Gaulard (France) and John Dixon-Gibbs (England) and a large Siemens AC generator. His AC systems basically sprung from there.
The downside to AC in the 50-60Hz range anyway, is the cycling can trigger muscle contractions which can cause your hand to grab a conductor and can cause atrial fibrillation.
DC causes far worse burns and tissue damage though as the current flows through continuously and it can also cause weird effects like electrolysis.
Both of them are pretty nasty at high current/voltage, but I wouldn't really give DC Edison's marketing safety approval.
The 230V 50Hz system is pretty rock solid and extremely safe, once you use it with the correct equipment and fixtures and fittings have evolved to become safer and safer over the decades.
[this post was last edited: 10/7/2021-11:09]