I need to know WHY some countries' electricity is at 50 Hz and others
are at 60 Hz.  I know the history of Heinrich Hertz and the beginnings
of electricity, and I know which countries use 50Hz and 60Hz, i just
want to know why there is a difference and when this decision was
made.

Hi ljungkull,

This answer comes from the IEEE or
Institute of Electrical and Electronics Engineers.

They should be considered THE
definitive resource for such 
a question.


[ http://www.ieee.org/organizations/history_center/faqs.html#60%20cycles ]
"Why does US use 60 cycles and Europe use 50 cycles?
Many frequencies were used in the 19th Century for
various applications, with the most prevalent being
the 60 c/s supplied by Westinghouse-designed central
stations for incandescent lamps. The development of
a synchronous converter which operated best at 60
cycles encouraged convergence toward that standard.
Around 1900, the introduction of the high-speed
turbine led to settlement on two standards: 25
cycles for transmission and for large motors (this
had been a compromise decision at Niagara Falls),
and 60 cycles for general purpose systems.
Meanwhile, in Germany, AEG -- which used 50 cycles
-- had a virtual monopoly, and this standard spread
to the rest of the continent. In Britain, differing
frequencies proliferated, and Britain only settled
on the 50 cycle standard after World War II."
(For more information on ac standards, we recommend
Hughes, Thomas P., Networks of Power:
Electrification in Western Society, 1880-1930,
Baltimore, USA, Johns Hopkins University Press.)


-=+=--=+=--=+=--=+=--=+=--=+=--=+=--=+=--=+=-

Search terms used:

AEG westinghouse niagara 60hz 50Hz
[ ://www.google.com/search?&q=AEG+westinghouse+niagara+60hz+50Hz ]

AC Power 60hz 50Hz
[ ://www.google.com/search?&q=AC+Power+60hz+50Hz ]

Three-phase Power 60hz OR "60 cycles"
[ ://www.google.com/search?q=Three-phase+Power+60hz+OR+%2260+cycles%22 ]

countries 50 60 HZ OR cycles electricity OR AC
[ ://www.google.com/search?&q=countries+50+60+HZ+OR+cycles+electricity+OR+AC ]


thanks for your question,
-AI

Thank you.  The book recommendation is also very helpful.  I
appreciate this researcher's ability to answer my question as I asked
it and that s/he did not give me any speculation or irrelavant
information.

I think the choice of frequency is pretty arbitrary and people may
just happen to have made it differently.

The big decision was whether to do DC or AC (and IIRC Edison argued
with Westinghouse over this).  Then once you are AC you need to decide
which of the supply properties you want to be least variable.  Making
frequency least variable makes it useful for electric clocks.

I believe that there was also a desire to be different.

Look at the arguments between Edison & Tesla.

>The big decision was whether to do DC or AC (and IIRC Edison argued
with Westinghouse over this).  

Edison also campaigned in favour of using AC for the electric chair
since this would make DC seem a better option for domestic use.

Ian G.