110, 115, 120, 125, 220, 240, what the heck is with all these numbers?

[LoudMusic]

I recently had someone insisting to me that the US electrical standard was 110v. I said, "Actually it's 120 and 240 currently. Ha ha puns!" But that got me wondering why everyone thinks it's 110.

I found this video.

And this bit of Wikipedia knowledge.

Mains electricity - Wikipedia

en.wikipedia.org

I've also found discussions on other sites.

History of secondary voltages in US - Electric power & transmission & distribution - Eng-Tips

I am writing an article and I would like to find out if there is some history (real numbers) of secondary voltages in the US. That is voltages actually supplied

www.eng-tips.com

Which includes, "I remember reading (and I have been looking for the reference for decades now) that a decision was taken to increase the voltage to 150 Volts. This was to be done at the rate of 1/2 Volt per year." I find that very interesting.

Theoretically we could eventually get to pretty high voltages arriving at residences which could provide much higher rates of charge for EVs at home.

The better solution would probably be to just start dropping 480 into homes and have bi-directional CCS.

 

[petit_bateau]

There is a reason we often write 220/240. But if you want real confusion look at the poor Japanese - two voltages AND two frequencies AND two plug types

Leads Direct | What is the difference between UK voltage and European voltage

Full list: Plug, socket & voltage by country - World Standards

Below is a complete overview of all countries of the world and their respective plugs/outlets and voltages/frequencies used for domestic appliances.

www.worldstandards.eu

Mains electricity by country - Wikipedia

en.wikipedia.org

 

[LoudMusic]

That's nuts. And that site lists Japan as 100v? I was mistakenly under the impression we had more similar power than that.

 

[petit_bateau]

That's nuts. And that site lists Japan as 100v? I was mistakenly under the impression we had more similar power than that.

You have to look at the history of the Japanese electrical system to realise how they came to this place. One of the hardest markets to break into if you are exporting electrical gen kit into it.

 

[adiggs]

Not an electrician, but my own impression (partly driven by closely watching charge rates on the Roadster during a long road trip) is that 240v is the nominal or targeted power (pretty sure that isn't the correct electrical term here), but that at higher amperage levels, the voltage drops and is found more routinely around 220v in practice. I also recall, but could be very wrong about this, that voltage can pull down to around 200v in some cases (such as drawing 80a on a 100a circuit on a sustained basis).

Similar deal with the 110s - they are nominally 120v circuits but pull down to 110v commonly enough that we think of and refer to them as 110s.


On that road trip, in theory, I should have been routinely charging at 240v * 80a = 19.2kw. In practice I saw that at one charger, one time. Most of my actual charging, when using a Roadster specific charger, was more like 14-16kw (closer to 200v * 80a = 16kw; sometimes didn't get the 80a either). But hey - way better than the 200 - 240v * 40a = 8 - 9.6kw I get in my garage using the RV / 50a plug.

 

[Ampster]

In practice I saw that at one charger, one time. Most of my actual charging, when using a Roadster specific charger, was more like 14-16kw (closer to 200v * 80a = 16kw; sometimes didn't get the 80a either

Some commercial installations which are three phase have voltages of 120/208 or 277/480 Volts

 

[CrazyRabbit]

the reason is people are dumb... but they do care about the color of socks they are wearing right now! like the influencer who had the clock on the wall upside down...
see this link, good explanation of the history.

Voltage Ratings: 110/115/120, 220/230/240 or 440/460/480

This subject comes up a LOT in this and other forums, so I thought it would be a good idea to make it a "Sticky" that can be found and referred to easily when it comes up. There are two "standards" for voltage in North America depending on which END of the wire you are looking at; "Distribution...

forums.mikeholt.com

 

[MontyFloyd]

Japanese - two voltages AND two frequencies AND two plug types

Japan is 1 voltage (100V), and nearly same plugs as US (the 2 prong lacks the taller polarized plug, but if plug does not have it, works just fine).

 

[MontyFloyd]

The better solution would probably be to just start dropping 480 into homes and have bi-directional CCS.

US houses are 240V, so we good (YES on C2H / bi-directional)

 

[petit_bateau]

Japan is 1 voltage (100V), and nearly same plugs as US (the 2 prong lacks the taller polarized plug, but if plug does not have it, works just fine).

Japan has both 200V and 100V in single phase (though the 200V is less common, much like 220/240V exists but is less common in USA 1ph); and 200V and 415V in 3-phase; and 50Hz and 60Hz. For these and some other (very protectionist) reasons it is a nightmare if you are a manufacturer of electrical equipment looking to import. Especially if you have Japanese competitors. You may not have encountered the 200V 1ph with a different plug but it does exist.

Electricity sector in Japan - Wikipedia

en.wikipedia.org

Electricity

Basic information about electric plugs, current and voltage in Japan.

www.japan-guide.com

Full list: Plug, socket & voltage by country - World Standards

Below is a complete overview of all countries of the world and their respective plugs/outlets and voltages/frequencies used for domestic appliances.

www.worldstandards.eu

Mains electricity by country - Wikipedia

en.wikipedia.org

 

[MontyFloyd]

Japan has both 200V and 100V in single phase (though the 200V is less common, much like 220/240V exists but is less common in USA 1ph); and 200V and 415V in 3-phase; and 50Hz and 60Hz. For these and some other (very protectionist) reasons it is a nightmare if you are a manufacturer of electrical equipment looking to import. Especially if you have Japanese competitors. You may not have encountered the 200V 1ph with a different plug but it does exist.

Ah, the lesser used special purpose plugs.