ntt@dciem.UUCP (Mark Brader) (07/07/84)
There was a column in yesterday's paper reminiscing about the time
when the Toronto area was converted to 60 Hz electrical supply.
I had believed that 110 V, 60 Hz, was practically universal in North
America fifty or sixty years ago, and then there was a change to 120 V
sometime. In fact, Toronto was not brought into line until the period
1954-59; the former supply was 25 Hz, for all of Southern Ontario.
Can anyone either comment on, or point me to a reference on, this matter?
For instance:
- Were there other large cities that were late to standardize?
(I remember reading something about Chicago once.)
- If so, what did they use? (Frequencies, AC, DC; other voltages too?)
- When did 60 Hz really become a standard in North America?
- Am I right about 110 -> 120 V, and if so, when did that happen?
- And what about other countries? When did they standardize?
Was there ever a chance of the world settling on one approximate
standard voltage and frequency instead of two of each?
Unless your reply is of general interest, mail to:
{ allegra | decvax | duke | ihnp4 | linus | watmath | ... } !utzoo!dciem!ntt
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Mark Brader, NTT Systems Inc.ron@brl-tgr.ARPA (Ron Natalie <ron>) (07/09/84)
If Thomas Edison had his way we'd be using D.C. and there would be little generating plants every couple of miles to power things. The Johns Hopkins University whose power plant generated the university's power in the old days was D.C. They finally got the last of the old elevators and stuff converted so they could finally put the D.C. generator out of commission. It happened in 1979. -Ron
john@hp-pcd.UUCP (07/10/84)
Nf-From: hp-pcd!john Jul 17 10:08:00 1984 Its to bad that the world started out with 60 hz instead of something higher. I have seen military equipment designed in both a 60hz version and a 400 hz version and the difference in weight is enormous. John Eaton !hplabs!hp-pcd!john
chris@umcp-cs.UUCP (07/10/84)
Edison was right, even if he was wrong. Back then it may have been
a ``good thing'' that Tesla won out, but it turns out that at the
voltages now in use on major power transmission lines have *more*
loss than they would if they were D.C. (At lower voltages, A.C.
is less lossy.) I don't remember where D.C. becomes more efficient
than A.C., but 760kV is above that point.
[Insert disclaimer: this is all from memory, so don't trust it too
much.]
--
In-Real-Life: Chris Torek, Univ of MD Comp Sci (301) 454-7690
UUCP: {seismo,allegra,brl-bmd}!umcp-cs!chris
CSNet: chris@umcp-cs ARPA: chris@marylandivy@ihuxt.UUCP (07/12/84)
If Thomas Edison had had his way, we might be using DC for a couple of reasons. His main incentive FOR selecting DC over AC was the fact that (at the time) small AC motors did not exist. Besides the famous electric light bulb, Edison saw numerous uses for small electric motors in the home, and provided for it. It was a good choice at the time, but development of better AC machinery quickly obsoleted it. He also had a good reason to AVOID 60 Hz. It was known that, in an electrical accident, AC is more deadly than DC, and 60 Hz is the most effective frequency for stopping a heart. The Edison electric company advertised the fact that the competition's AC generator was chosen, for exactly that reason, to be used in the first electric-chair execution. The economics of AC won out, what with the wonderful things that can be done with transformers converting and isolating voltages, and motors that are smaller and longer-lived than a DC motor of the same power, and long-distance, high-voltage, transmission lines. And technology kept evolving, and capacitors got smaller and more efficient, and solid-state electronics became ever more subtle, and long-distance, high-voltage DC transmission is now most economical, and hospitals are installing DC power for safety's sake, and environmentalists are worried about the effects of AC fields on the mind... Now that everyone, even John Hopkins University, has caught up with the world and switched to AC, it may be that the world is turning back to DC.
hrs@houxb.UUCP (H.SILBIGER) (07/12/84)
The actual line voltage in your house is 117 volts 60 Hz single phase to ground. The voltage coming into your house is 220 V ungrounded. If you have a central airconditioner or electric range it runs on 220 V. If you take one of the conductors and measure it to ground you get 117 V. Some parts of NYC (lower Manhattan)were DC until about 20 years ago. These were remnants of the Edison power system. The 50 Hz systems were generally of European origin, and the 60Hz systems of US origin. If the first power company in a country was financed or built by US interests, it has 60 Hz, otherwise 50 Hz. This is very noticeable in South America, were for example Venezuela is 60 Hz and Argentina 50 Hz. On St Maarten, a tiny 17 sq mi island in the Caribbean, which is hal French and half Dutch, the dutch side is 117 V and the French side is 22o V, but bothe are 60 Hz! Japan is part 50 Hz and part 60 Hz. The 60 Hz part is 100 V. Many AC rail systems run at low frequencies, in Europe 16.67 Hz. The NY IRT subway had generators that were 30 Hz I think, which was rectified beause the trains ran on DC. The lights in the stations were run on AC and flickered visibly. I don't think there will ever be a worldwide standard. Herman SDilbiger
mmt@dciem.UUCP (Martin Taylor) (07/13/84)
************
Edison was right, even if he was wrong. Back then it may have been
a ``good thing'' that Tesla won out, ...
************
I don't know about Tesla, but in the UK it was Ferranti who led
the fight for AC power distribution. Even Punch had comments about
it. Ferranti built the Battersea (I think; maybe it was Deptford)
power station, and eventually built his company into one of the
premier electric (and later electronic) companies. While it was
totally owned by the Ferranti family, the company was always more
interested in future development and engineering effectiveness than
in current profits. Eventually, this led to their downfall, when
they entered a low bid on a fixed-price missile guidance project.
As one would expect, they factored in costs for engineering redesign
and debugging, but the system worked first time, six months early
and 5 million pounds under budget. The press and the Govt got after
them as black profiteers, and they had to pay back L5,000,000 cash.
The alternative was a threat that they would never again get a Govt
contract. Engineering excellence does not always pay!
--
Martin Taylor
{allegra,linus,ihnp4,uw-beaver,floyd,ubc-vision}!utzoo!dciem!mmtron@brl-tgr.ARPA (Ron Natalie <ron>) (07/16/84)
Yes, electric current is the problem with train service in Europe. Even though they are supposedly cooperating you still have to change locomotives at the border. Better, I suppose than going from Poland to Russia, where you have to stop and change the trucks from the standard guage to the 5' Russian ones. -Ron
hrs@houxb.UUCP (H.SILBIGER) (07/17/84)
Actually train service is not a problem any more with the cahnges in voltage and frequency. New lectric locomotives generally rectify and then use chopper control. These locomotives or trainsets can run in the Netherlands (1500 V DC), Belgium (3000 V DC), France, Switzerland (AC), and otherplaces. By the way, Spain also is broad gauge, and there are through trains which have trucks that change gauge automatically!
ijk@houxt.UUCP (07/18/84)
Traveling in Italy several years back, the voltage in our Florence hotel was something really unusual (165 volts, I think). We used a portable iron - I looked at the light bulbs and saw the leading 1 and thought it was the lower voltage). Blew the fuses for our entire floor. Talk about standards - we don't need no stinkin' standards.... Ihor Kinal
ron@brl-tgr.ARPA (Ron Natalie <ron>) (07/20/84)
Most of the current in Northern Italy is 220V 50hz. We were given a pastamatic and I run it off a step down transformer. -Ron
mmt@dciem.UUCP (Martin Taylor) (07/21/84)
**************
Its to bad that the world started out with 60 hz instead of something higher.
I have seen military equipment designed in both a 60hz version and a 400 hz
version and the difference in weight is enormous.
John Eaton
**************
But the power losses in transmission would have been enormous at 400 Hz.
This is presumably why some places (like Southern Ontario) started at
much lower frequencies such as 25Hz.
--
Martin Taylor
{allegra,linus,ihnp4,uw-beaver,floyd,ubc-vision}!utzoo!dciem!mmtsef@drutx.UUCP (FarleighSE) (07/23/84)
. 400Hz is quite common if you're in military aviation. With the higher frequency the transformers (step-up, down or isolation) are much smaller. Therefore a weight savings is realized. I don't know about commercial aircraft though.