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Joined: Sep 2003
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Los Angeles ran 50 Hz until 1948. They switched over to 60 and it cost 34 million 1948 USD to get their 765,000 customers online. https://gizmodo.com/before-1948-las-power-grid-was-incompatible-with-the-r-1683629042

Japan has the same problem and it's just too much to unify the line frequency,

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Originally Posted by GeneSF
Los Angeles ran 50 Hz until 1948. They switched over to 60 and it cost 34 million 1948 USD to get their 765,000 customers online.

Interesting!

Thanks for the info!

Bill


Bill
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Glad to contribute, Bill. Domestic and overseas configurations got me over to this this group. I'm not a Electrical Contractor, but contractors have a firsthand knowledge of electrical systems and are the ones to listen in on. My past work involved calibration of electrical measuring equipment.

Gene

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Interesting reading !!

Thank you for the education !!



John
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Japan's 50/60 Hz dilemma splits the country in half, Tokyo is 50 Hz, Osaka 60 Hz.

One way around it is convert to DC using HVDC stations to tie the grids together The Shinano Frequency Converter station is one example.

It does limit how much power can be transferred, but changing one side to the same frequency as the other is logistically far worse than LA in the 1940s.

In fact I'm glad LA took care of it before development really got going.

Last edited by GeneSF; 07/31/19 11:55 PM.
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Apparently Japan was first electrified by the British, who use 50Hz.
Then the US bombed the country (something about a little picadillo called WW2).
When the US rebuilt the destroyed parts of the electric system after the war they used the 60Hz US standard frequency.

Thus arose the unique situation that if your job transfers you from one end of the country to the other you may not be able to take all of your appliances with you to your new home.


Ghost307
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This is where switcher power supplies come to the rescue. I was surprised that virtually everything I wanted to take to New Zeland had inputs 100-250v 50/60 hz. All I needed was a plug adapter and a cube tap to plug everything in.


Greg Fretwell
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Originally Posted by ghost307
Apparently Japan was first electrified by the British, who use 50Hz.
Then the US bombed the country (something about a little picadillo called WW2).
When the US rebuilt the destroyed parts of the electric system after the war they used the 60Hz US standard frequency.

Thus arose the unique situation that if your job transfers you from one end of the country to the other you may not be able to take all of your appliances with you to your new home.


I remember reading a story about Siemens (50 Hz) and GE (60 Hz), well before the war. That seems more likely to me! I also believe that most Japanese equipment is dual-frequency rated for that very reason. Make sure that all transformers and motors have enough iron to run on 50 Hz and if running speed of something with a motor is critical make it a belt drive with two pulleys or use a DC motor.

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Actually the problem started back in the 1890s and even after the war it continued. The allied occupation (well actually the US occupied the entire country post war) did not change that. Outlet voltage is still 100V vs the North American 120V. Since some Japanese domestic electronics can have problems at 120, 120 to 100 V stepdown transformers are still sold.

This article is a good summary of how and why it happened from a source in Japan.

https://www.japantimes.co.jp/news/2011/07/19/reference/japans-incompatible-power-grids/

Last edited by GeneSF; 08/01/19 04:40 PM.
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Thanks for the link.

I'm always interested in learning new things...and correcting things that I was taught long ago.
Apparently my history teacher told us the wrong thing (once again) back in school.


Ghost307
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