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Before 1948, LA's Power Grid Ran at 50hz
106 points by curtis
http://gizmodo.com/before-1948-las-power-grid-was-incompatible-w...___________________________________________________________________
Animats - 3 hours ago
Until the 1990s, Grand Central Station in New York had almost
everything - 60Hz commercial power, 40Hz LIRR power (Pennsylvania
Railroad standard) 25Hz NYC Subway power, 700VDC Metro North power,
600VDC subway third rail power, and some old Edison 100VDC power.
There was a huge basement area full of rotary converters to
interconvert all this. Various ancient machinery and lighting ran
on different power sources.In the 1990s, Grand Central was rewired,
and everything except railroad traction power was converted to
60Hz. All conversion equipment was replaced with solid state gear.
It took quite a while just to find everything that was powered off
one of the nonstandard systems.It wasn't until 2005 that the last
25Hz rotary converter was retired from the NYC subway system.
(Third rail power is 600VDC, but subway power distribution was 13KV
25Hz 3-phase.)
bogomipz - 46 minutes ago
>"Until the 1990s, Grand Central Station in New York had almost
everything - 60Hz commercial power,..."Do you mean 50Hz there?
zkms - 2 hours ago
> 60Hz commercial power, 40Hz LIRR power (Pennsylvania Railroad
standard) 25Hz NYC Subway power, 700VDC Metro North power, 600VDC
subway third rail power, and some old Edison 100VDC power.The
only thing missing is 400Hz power!
jacquesm - 1 hours ago
Isn't that usually used just for ships and aircraft?
jis - 1 hours ago
And old IBM computers!
Aloha - 4 hours ago
Growing up in Southern California, I remember always finding old
clocks with conversion stickers on them - I've been looking for a
good source on the technical details to find out what they needed
to do to accomplish the changeover. I'm not willing to pay 35 bucks
to read the IEEE article however.
baobrien - 4 hours ago
IEEE articles can be 'obtained' on Sci-Hub.
Aloha - 3 hours ago
Thank You!!
dom0 - 4 hours ago
Pretty much the only way would be to either swap the gearbox
connected to the synchronous motor, or the sync motor itself.
Aloha - 3 hours ago
Having read the article, yes this was a common way - sometimes
no conversion was required. Or a new motor was required,
because they were using a 60hz motor to start out with (a 60hz
motor running on 50hz makes more torque), and with the
frequency change the motor would no longer make adequate
torque.
zkms - 3 hours ago
> I'm not willing to pay 35 bucks to read the IEEE article
however.Me neither: http://ieeexplore.ieee.org.sci-
hub.cc/document/6444314/
rz2k - 3 hours ago
I have a ~10 year old GE microwave. After using a portable power
generator which probably does not have a very accurate frequency,
this winter when the grid was out, it seemed to switch itself
over to 50Hz, and stayed that way after electricity from the grid
was restored.It was very confusing as the clock consistently ran
too fast, and the timer ended before food got as hot as it
previously had. I was surprised that something like that would be
built into the microwave, and that it would be able to guess
something like that. Eventually I unplugged it for a couple
hours, and it went back to normal when I plugged it back in.
ChuckMcM - 3 hours ago
I recall finding a 'frequency converter' at a surplus store in LA
from around the time of the war. Basically it was a motor
generator set, the motor ran on 120V AC 50Hz and the generator
produced 120V AC 60Hz. I asked about it and it was the first I
had heard that LA had been 50Hz at one time.I presume it was used
in a lab or something, it weighed quite a bit and didn't look
like something you'd have on your kitchen counter.
lb1lf - 4 hours ago
Incidentally, Japan faces this very issue to this day; part of the
country run on 50Hz, the rest on 60Hz.This made matters trickier
after Fukushima, as the nation is effectively two smaller
electricity grids, not one large one - so making up for the
shortfall became harder than it could have been. (However, there's
a massive frequency converter interface between the two
grids.)Edit: Aw, shucks - now that I revisit the article, I see the
exact same points being made in that article's comment section. My
bad.
Libre___ - 3 hours ago
First thing that came to mind here too. Wikipedia has some
fascinating reading about the GE and AEG networks in Japan:
https://en.wikipedia.org/wiki/Electricity_sector_in_Japan
janvdberg - 2 hours ago
This 99% invisible episode also talks about this (third segment):
http://99percentinvisible.org/episode/you-should-do-a-story/
wolfgang42 - 2 hours ago
I had a Waring Blendor [sic], cat. no. 700A, with the widest range
I've ever seen: "115 Volts, 6 Amps, 25 to 60 cycle A. C. - D. C." I
haven't been able to pin down an exact date on this model, but it
seems to date from the 1940s or so, when the U. S. power grid still
hadn't completely settled on a standard. I've read that portions of
Boston still had 110 volts DC in residential areas up through the
1960s, though I've been unable to find much detail about this.
mysterypie - 1 hours ago
> customers could bring their old 50hz appliances for free
adjustments and exchanges, [including] 380,000 lighting
fixturesSurely ordinary light bulbs don't care about the frequency.
Do they mean the electronics for fluorescent lamps? Were those
common in the 1940s?
workerIbe - 1 hours ago
I wish we still had these. I run half my house "off grid", my
inverter is putting out 61Hz and my old digital alarm clock runs
fast.
MBCook - 1 hours ago
The most recent episode of the podcast 99% invisible talked
about this. Basically anything with a motor needed to be
replaced or somehow changed so the motor would run at the right
speed.If you didn't, your electric clocks would run 12 minutes
fast every hour (for example).
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ryandrake - 1 hours ago
My mind always boggles at humanity's general inability to
standardize on one thing without great pain and fighting. Whether
it's Metric vs. Imperial, Beta vs. VHS, Blu-ray vs. HDDVD, OpenGL
vs. DirectX, USB speeds, power connectors, instant messaging
protocols. Nobody can just sit together and cooperate--we always
have to go through that painful period with multiple incompatible
standards that fight it out until (hopefully) one of them wins.
zanny - 51 minutes ago
Standards forfeit control. If you can become a de facto standard,
without standardizing, you wield insane power over lives and
business. Of your examples, Blu-ray, DirectX, and the "new age"
closed silo IM protocols like WhatsApp that superseded an XMPP
world are all corporate controlled properties that have no
standards body considering the needs of the industry. They behave
and act to fulfill the needs of their creators, to the detriment
of the users and broader ecosystem.That is why standards are
hard. Because it requires those with power to voluntarily
relinquish it, which very rarely will happen. And then to never
try to circumvent standards with first mover advantage to reclaim
that kind of monopoly power. At least right now societies around
the world are very poorly structured to align the incentives
towards cooperation.
esolyt - 42 minutes ago
> Whether it's Metric vs. ImperialTo be fair, humanity did
standardize that long ago. There is a country that is refusing to
switch to the standard.
mmmpop - 17 minutes ago
Maybe if every American took a thermodynamics course where the
teacher insisted on memorizing the unit conversions we would
not have this issue! What an awful semester...
jdboyd - 42 minutes ago
With regard to OpenGL vs. DirectX, the competing standards push
each other to keep improving. I suspect that graphics APIs and
thus hardware would have really stagnated without the
competition.
Denvercoder9 - 40 minutes ago
Well, different systems have different tradeoffs. It makes sense
that people have different priorities, and thus prefer different
systems. Almost everyone likes cooperation, but for that
compromise is needed, which is always difficult to achieve in a
manner satisfactory to all parties involved.
cmurf - 12 minutes ago
My favorite example of this at the moment is UEFI Time Services.
Time is current local time, TimeZone is an offset from UTC in
minutes, and Daylight establishes whether DST should apply, and
if it has been applied. So yay, no more time incompatibilities
with multiple OS's. Except no, not even Microsoft Windows 10 sets
the TimeZone value to the actual UTC offset! They set it to
EFI_UNSPECIFIED_TIME. And so does Linux. And so does macOS. So
we're still fakaked.
Tharkun - 1 minutes ago
Blame all those cheeky buggers who built machines powered by
steam engines or water turbines. They basically built their
machines to run on whatever was available. Got a waterwheel doing
1000RPM and you need a big saw attached to it? Your saw will be
running at 1000RPM (~16Hz).So many crazy machines were built
before there was either a need or an effective way to standardize
anything power related. Keep in mind that many kinds of
manipulations of electricity are easy and cheap now, but that
certainly wasn't the case when people started converting from
steam/water to electricity!
unabridged - 1 hours ago
Language is probably the oldest (and most sentimental) version of
this problem
andreasgonewild - 1 hours ago
Only because of isolation, look at what's happened in only a
few years since we got our hands on a global network.
zanny - 56 minutes ago
There is still an incredible amount of isolation. My primary
forums are reddit and hacker news, and both are so
disproportionately Americo-centric its scary. Google only
ever gives me results from American publications and even
Duckduckgo has a hard time finding relevant information to my
searches from outside the US or West Europe.Meanwhile, more
people in Africa have cell phones than plumbing, and there is
realistically almost nowhere in the world without some form
of cellular data service now. All these people, however, are
in isolated language specific silos of content. Even the
Indian Internet is radically different from what I see
despite both being in mostly the same language (with some
Hindi mixed in).I am always worried about how little
interaction there is, through a medium of effectively no
barriers than the ones we make ourselves, between the people
of western powers and everyone else who is currently online
but either not informed about what the Internet is (and thus
just uses SMS) or is isolated from us by language barriers.
andreasgonewild - 1 hours ago
That would be capitalism's general inability.
hugi - 1 hours ago
I'm actually rather impressed with humanity's ability to
standardize. It's perfectly natural (and in many cases desirable)
for multiple parties to go through that "painful period" with
different solutions that will compete to become "standard". It
just takes a little time for everything to align and settle,
that's perfectly natural.As for the U.S. refusing to adopt the
planet-wide metric system? You've got me there. That's just?
Weird.
zanny - 1 hours ago
It should be obvious why the US stays on the imperial system.
There is an opportunity cost to switch that is greater than the
current ongoing cost of translation. Thus, someone has to bite
the bullet and assume losses to push metric. Throughout the
world, the organization that put the foot down and ate the bill
has almost always been the government - but the US government
operates on short term results. The politician that
inconveniences the public today with a metric conversion
doesn't have his seat tomorrow, and his replacement immediately
halts proceedings.Language isn't close to a solved problem.
Hopefully the next hundred years can finally see the
reconstruction of the Tower of Babel for a generation of the
world soon to come. But there also needs to be a legitimate
reason for us to want to unify language. If we operate
independently of one another and let businesses control any
interactions by proxy of money, we will stay separate.
esolyt - 33 minutes ago
The problem is public opinion. Americans either don't care or
think imperial is superior.It doesn't have to be a federal
law. Change can start gradually with private companies.
Pokemon Go, for instance, shows only kilometers and doesn't
offer imperial units as an option. All water bottles in the
US have both mililiters and fluid ounces on their label.
hugi - 11 minutes ago
Once the US has lost it's political importance, the Internet
won't convert to U.S units. Conversion to metric will
eventually happen.As for language, I'm kind of split. On one
hand language is a tool for communication that becomes more
efficient the more standardized it is. On the other hand,
language is closely related to art and culture. I'm Icelandic
(and a poet at heart) and I love my language deeply. I can
succintly say things in Icelandic that can't esaily be
expressed in English. And that probably applies to every
language.So I'm torn. I don't want to lose my language. But I
also want a more integrated world.
plorg - 3 hours ago
It took a long time to standardize and integrate the US power grid
(which even today is basically 3 loosely-connected systems). Some
parts held out longer than others.My brother recently visited a
hydro dam in northern Minnesota that had one turbine operating at
25hz even as recently as the 90s, serving at least one industrial
customer still running equipment that predated the interconnected
60hz grid.
lostlogin - 3 hours ago
You prompted me to look up how power stations are synchronised.
This rabbit hole leads to The War of Currents. It's worth a
read.https://en.m.wikipedia.org/wiki/War_of_Currents
johnhenry - 2 hours ago
The saddest casualty of war being Topsy :(.
jakobegger - 2 hours ago
It?s amazing how much opposition there apparently was against
AC current ? a technology that noone is afraid of today.
Gibbon1 - 1 hours ago
The open question for me is why did Edison even bother with
DC at all? A DC generator requires a commutator. If there is
anything that screams dodgy, that would be it.Sliding
friction. high current contacts. 60 times a second?
Seriously?
xxpor - 23 minutes ago
Do incandescent bulbs last longer with DC, since they're
not switching on and off 60 times a second?
Gibbon1 - 2 hours ago
I've seen a few cases where there was a need to run 120VAC a
thousand feet or so. The most cost effective solution being to
step the voltage up to 240VAC and then back down at the load.
Basically you save 75% on wires which pays for the two
transformers. Bonus, you can use a tapped transformer to
compensate for line loss.120VAC -> 1.0T2.0 -> 240VAC --> line
--> 220VAC --> 1.8T1.0 --> 120VAC
lostlogin - 1 hours ago
Where I am it's 240v to start with - presumably The Current
War wasn't conclusive.I understood it to make transmission
easier but the US would face that problem at least as much as
anywhere else...
vvanders - 58 minutes ago
Ironically I was reading recently(wish I could find the source)
that some power distribution is switching back to DC due to the
inductive load that the AC wave generates over long distances.
Solid state has come along far enough that the conversion
losses are comparable with AC transformers.
agumonkey - 3 hours ago
Similarly the history of voltage levels:
https://en.wikipedia.org/wiki/Mains_electricity#History_of_v...
camtarn - 1 hours ago
The vibrating reed frequency meter which is the lead image in
your link is super cool - never thought about a meter using tuned
resonators to measure frequency instead of a discrete time-based
counter.
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gumby - 3 hours ago
There are other, smaller countries that have mixed frequencies.PG&E
(California' primary gas and electric utility) still has DC
tariffs, thought I believe they provision it by installing a
converter at the pint of use. I believe this is just for
elevators.Parts of Back Bay in Boston were still wired for 100V DC
mains voltage into the 1960s
seandougall - 3 hours ago
Fascinating -- I'd always heard that 24 fps developed as a US film
standard compared to 25 fps in Europe because of the difference in
AC power frequency (24 and 60 being a pretty straightforward
integer ratio). And yet, during this time, LA became firmly
entrenched as the center of the American film industry while
producing 24 fps films. I wonder how that squares -- was this
something people had to deal with, or does this article possibly
overstate how widespread 50 Hz power was?
elihu - 44 minutes ago
I've heard of European broadcasters speeding up a film slightly
so that it's 25 fps instead of 24. Thus the same movie could be
several minutes shorter on European broadcast TV. As long as the
speed difference is small enough, people don't notice.
aninhumer - 2 hours ago
The power frequency isn't that relevant for film, since it just
powers motors on the cameras and projectors (or often just hand
cranked). In fact, prior to the introduction of sound in films,
the exact playback speed wasn't as important, and cinemas often
varied.Where it becomes relevant is for television, and in both
cases the refresh rate matches the mains frequency. PAL is 50Hz
interlaced, and NTSC is 60Hz interlaced.
acchow - 2 hours ago
I had to read further to understand why Cathode Ray Tube
televisions were tied to mains frequency - it's due to an
effort to reduce
artefactinghttps://electronics.stackexchange.com/a/164252
wonderous - 2 hours ago
This article covers the topic in more detail, but the general
gist is that the film speed was controlled by the projectionist
not the camera man recording the film, which was a set speed and
powered by hand:http://gizmodo.com/why-frame-rate-
matters-1675153198
digi_owl - 2 hours ago
Nah, the 24 frames is the lowest frame rate before we sense the
individual images. Leads to less film usage.Note btw that we need
60 frames to get lifelike.And gamers often want higher because
the input sampling of a game is hooked up to the frame rate, so
the higher the rate the more responsive the controls are...
ko27 - 2 hours ago
And 25 isn't? Do you honestly believe it was one big
coincidence?
digi_owl - 1 hours ago
I have never heard any talk about there being a separate film
standard for europe, beyond the needs for converting to PAL
for home movie use.And only at that point do the whole 25
frame make sense, and something that can be dealt with by
inserting an extra frame ever so often.
pavlov - 1 hours ago
I went to film school in Finland around 2000, and I
remember that 25 fps was the preferred production and
projection rate for 35mm. I got the impression that this
was common practice elsewhere in Europe as well, but I
don't know for sure.
acchow - 1 hours ago
I think the point is the film framerate was chosen to
match the TV framerate, not the other way around.Before
TVs were invented, we had actual films being rotated by
hand crank or by a motor - their fps is independent of
electrical mains. But cathode ray tube TVs were made to
match mains frequency. Then to avoid having to do some
kind of conversion, it was easier to film your movies to
match TVs.
pavlov - 29 minutes ago
Right, standardizing on 25 fps in Europe came from PAL's
25/50Hz rate.I think 24 fps for sound film originally
arose from the requirements of the optical soundtrack:
slower running 35mm film wouldn't have enough resolution
for decent sound quality. That's my guess anyway.Silent
films were often shot on slower rates around 16-18 fps
(which explains the widespread comic "speed-up" look for
video copies of silent movies, as the transfer was done
the easy way by playing it back at 24).
Koshkin - 1 hours ago
This is correct.
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