
A legacy from the 1800s leaves Tokyo facing blackouts - abennett
http://www.itworld.com/business/140626/legacy-1800s-leaves-tokyo-facing-blackouts
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kevinpet
If the grid supports it, they might be able to switch over some generators
near the crossover point from 60hz to 50hz. California's San Francisquito
hydro plant has been running 50hz turbines from the 1920s at 60hz for decades
with no problems. I'm sure you can go the other way as well.

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rchen
They are indeed making preparations to do this, with two of the hydro plants
in Nagano (normally producing 60hz) near the crossover point: Ontake and
Nezame. Combined they produce about 70,000 KW
[http://www.nikkei.com/news/category/article/g=96958A9C93819A...](http://www.nikkei.com/news/category/article/g=96958A9C93819A96E3E1E2E2918DE3E1E2E1E0E2E3E3E2E2E2E2E2E2)

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robin_reala
I’ve often wondered if there are any advantages/disadvantages to the differing
electrical frequencies. Any electrical engineers able to enlighten me?

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jordanb
I'm not an EE so maybe this is all wrong, but from my understanding, Nikola
Tesla determined that the optimum way to transmit power in the early days of
AC was 240V@60HZ. 240V was the best tradeoff between safety and voltage drop,
and 60HZ was the most efficient frequency for generators and motors.

The United States ended up on 120V because of Thomas Edison's lobbying, but
took Tesla's recommendation of 60HZ. Europe took Tesla's recommendation of
240V but adjusted the frequency to the "more metric" 50HZ.

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brudgers
In the US power transmission is three phase at high voltage (which is where
voltage drop is really a big concern). Voltage drop within a building is
rarely a concern in the vast majority of buildings.

Typical electrical service for small buildings is 240v using two of the three
legs. At the service panel each of the legs is available separately as 120v or
in combination as 240v. Larger buildings and industrial applications will
often use 208v three phase services for power efficiency. Higher 3 phase
voltages are also used on a more limited bases

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lutorm
Actually, at least in Sweden, 3-phase 380/400V is available in most homes for
power-hungry things like electric stoves, water heaters, etc. I've never seen
this in the U.S, so combined with the lower voltage, you need really thick
wires to support the 20+A you need to run a 2500W stove. Seems like a waste of
copper. I wonder if the U.S. resistive losses are noticeably larger than in
Europe. Certainly you notice extension cords for things like vacuum cleaners
get very warm in the U.S.

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dmm
In the USA dryers and electric stoves are connected to 240V, and use different
plugs. I have never seen an electric dryer that operates from 120V.

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billswift
Ranges are 240V and 50 Amps; clothes dryers are 240 V and 30 Amps. Both have 3
prong plugs that are much larger than 120 V outlets, the dryer plug has an
L-shaped prong so it can't be inserted into a range outlet. (The reason you
don't want the dryer plugged into a range outlet, is the internal wiring is
inadequate for 50 amp loads, and can burn out without tripping the 50 amp
breaker on range circuits.)

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msisk6
It might surprise some folks to find the US isn't much different. Although
here in the US we're all at 60Hz, we have several regions with different
synchronization: <http://en.wikipedia.org/wiki/Wide_area_synchronous_grid>

So we also have interconnections with limited capacity between the grids. I
recall reading about a new interconnection plant being built between three of
our grids on the border of NM and TX with superconducting cables, but can't
find the link. Maybe someone else can post it.

~~~
JimmyL
I suspect you're thinking of the Tres Amigas SuperStation
(<http://www.tresamigasllc.com/>), which will connect the Western, Eastern,
and Texas Interconnects - and should realistically be online in 2015 or so.

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jdavid
In the case of an emergency like this. I would think that most 60hz devices
could work on 50hz, and most 50hz devices would work on 60hz.

things that would get screwed up are devices that use the signal to time
events. some high voltage switches use these things, but overall, i bet
washing machines, dish washers, computers, lights, tvs, and radios would just
work.

even garage door openers should work.

clocks and larger equipment might be a bust and maybe some of the robotics
stuff at plants might be a bit off, but maybe just maybe it would work. these
things are designed to condition the power in most cases within a few
percentage points anyways.

i bet if it's that dire, they give it a go.

~~~
patrickyeon
The problem isn't running your commodity devices on the different frequency
(most stuff you mentioned transforms and rectifies the wall power, so it's all
DC anyway). The problem is getting the grid to work together. West Japan can't
send enough power over to East Japan, because the signals don't line up, to
leave out the technical bits.

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rchen
For those familiar with Japanese geography the 60hz and 50hz grids are broken
up like this:
[http://ja.wikipedia.org/wiki/商用電源周波数#.E6.97.A5.E6.9C.AC.E3.8...](http://ja.wikipedia.org/wiki/商用電源周波数#.E6.97.A5.E6.9C.AC.E3.81.AE.E5.95.86.E7.94.A8.E9.9B.BB.E6.BA.90.E5.91.A8.E6.B3.A2.E6.95.B0)

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riobard
It's amazing that a country known for its industrial standards is stuck with
such ancient compatibility issues.

