[ELI5] How did we decide on 120V and 220V for house electricity? what about 50hz and 60hz? whats so special about those numbers?

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[ELI5] How did we decide on 120V and 220V for house electricity? what about 50hz and 60hz? whats so special about those numbers?

In: Technology

2 Answers

Anonymous 0 Comments

Copy from u/the-hundreth-idiot

“We use 120 volts because Edison chose 110 volts DC for light bulbs. And that was because he couldn’t figure out how to create bulbs running on 220 volts without burning out (as /u/Legillo said).

So the question really is, why doesn’t Europe and the rest of the world use 120v?

Originally Europe was 120 V too, just like Japan and the US today. But in the 50’s or 60’s they were able to change to 220 V. It’s an advantage because with increased voltage you get more power with less losses and voltage drop from the same copper wire diameter.

At the time the US also wanted to change but because of the cost involved to replace all electric appliances, they decided not to. The average US household already had a fridge, a washing-machine, etc., but not in Europe.

Sources: TheDNetworks and StraightDope”

Anonymous 0 Comments

Regarding the 50hz and 60hz, not likely a particular reason for using either one they were just adopted as standards when it all started and has stayed that way.
What they mean is how many times per second the fluctuation from zero volts to 170 volts positive then back to zero, then to negative 170 volts then back to zero. That is considered one cycle which happens 50 or 60 times per second.