Talk:Utility frequency

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Contents 1 Tesla 2 Various 3 Stability 4 Requesting color change in the world map

[edit] Tesla

The text around history of 50 vs 60 has been shortened over the past half year, so for reference below is what i originally compiled in August 2006. I have no real argument with the subsequent edits, but thought there might be some interest in some of the further details (and caveats) in the longer text. --Psm 21:40, 5 January 2007 (UTC)

Though many theories exist, and quite a few entertaining urban legends, there is little certitude in the details of the history of 60 Hz vs 50 Hz. What is known is that Westinghouse in the US decided on 60 Hz and AEG in Germany decided on 50 Hz, eventually leading to the world being mostly divided into two frequency camps. What is also well understood is why the frequencies ended up in the 50-60 range: direct current generators that came online in the late 1890:s were more stable at lower rotation speeds, and the flicker of lighting becomes noticeable somewhere below those levels. Westinghouse decided on 60 Hz before 1892 and AEG decided on 50 Hz by 1899. Tesla is believed to have had a key influence in the choice of 60 Hz by Westinghouse, but it may simply have been happenstance: Westinghouse won the World Fair in Chicago (1893) lighting contract, and after that the Niagara Falls project, both of which were 60 Hz. Maybe it simply "stuck" as corporate decisions are wont to do. AEGs choice of 50 Hz is by some thought to relate to a more "metric-friendly" number than 60, which would be peculiar since it is distinctly less efficient than 60Hz. It may also have been an intentional decision to be incompatible. In any case, a plethora of frequencies continued in broad use. For example, London in 1918 had 70 electric authorities with 24 different voltages and 10 different frequencies. It wasn't until after World War II with the advent of affordable electrical consumer goods that broader standards were enacted.

Niagara started off at 25 Hz, with a good explanation by Lamme in the 1918 article. The Edward Owen article in Dec. 1997 "IEEE Industry Applications" says Stillwell of Westinghouse decided on 60 Hz in 1890, because arc carbons in the US at the time didn't work well at 50 Hz and 60 Hz would be OK for induction motors. AEG was related to General Electric, and GE used 50 Hz for Mill Creek but soon switched to 60 Hz; the Owen article says they were losing market share to Westinghouse. The Owen article also says that AEG moved to 50 Hz because the 40 Hz of the Lauffen-Frankfurt transmission gave some light flicker (and by this time Europe would have been using 240 V metal-filament lamps which were more sensitive than 120 V or carbon-filament lamps).

I didn't find a link between Tesla and 60 Hz except indirectly since the induction motor didn't work well with the 133 Hz single phase power of 1880; to use Tesla's motor with the materials available at the time required a lower frequency. In 1890 the whole world was within an eyelash width of all being 50 Hz.

Someone in the Baltimore Amateur Radio Club transcribed the 1918 Lamme article and put it on-line as a .PDF file (at [1]); anyone editing this article should read the Lamme paper, and I'd also highly recommend the Hughes book, too. --Wtshymanski 16:44, 5 November 2007 (UTC)

[edit] Various

I heard a rumor that higher-frequency waves on the power lines would increase efficiency and decrease losses.

I'm skeptical, and Utility_frequency#400Hz seems to say the opposite. Which is true? — Omegatron 17:41, 16 September 2006 (UTC)

The History section is a bit repetitive. The second half of that section says pretty much the same as the first, only in slightly different words. Perhaps someone ought to tighten that up a bit. 203.191.193.38 06:38, 4 January 2007 (UTC)

Yeah, this article has incorporated historical frequency texts from different sources, and would certainly be helped by some editing. --Psm 21:40, 5 January 2007 (UTC)

How does it look now? --Wtshymanski 16:44, 5 November 2007 (UTC)

Because of capacitance between lines, and between lines and ground, a higher frequency means more losses in the transportation of the energy. Conversely, a higher frequency requires smaller transformers, that can be cheaper or more efficient than lower frequencies. So, you gain on one side, and lose on the other.

[edit] Stability

The stability chapter on the main page claims that the line frequency is adjusted so that "at the end of the day" we are within reasonable accuracy. Another website claims that the power companies will run the frequency .01Hz fast or slow to bring it back so that there are exactly 216,000 cycles each hour. Which is right? Who controls the frequency, and how accurately do they keep it? Should I assume each hour has the right number of cycle, or each day? I suppose this needs to be answered on a per country or region basis. —Preceding unsigned comment added by 66.84.205.186 (talk) 23:45, 20 November 2007 (UTC)

I recently bought a Fluke digital multimeter which has a frequency counter built in, which resolves 0.01 Hz at 60 Hz. I've observed my local wall plug frequency (Manitoba, linked to the MAPP area of the North American electrical system) and I've seen as low as 59.98 Hz around suppertime during the week and up to 60.03 Hz on Sunday afternoons. This is consistent with lower frequency during heavy loads and trying to average out the frequency during the day, though I'm not checking nearly as often as necessary to verify the network's performance. --Wtshymanski (talk) 22:13, 14 February 2008 (UTC)

"System time", the integrated line frequency, is compared to real time by most operators. The UK system operator endeavours to keep system time and real time as close as possible, and to reduce accumulated errors through means of speed correction, though it does not do so on an hour-by-hour or even day-by-day basis. You can view real-time frequency data on their website. Operational limits for the UK are set at ±0.2 Hz, rather more than the ±0.02 Hz Wtshymanski has observed in Canada, though the North American (and, for example, continental European) systems have substantially more system inertia than the essentially islanded UK system. This acts to considerably stabilise the supply frequency. — BillC ^talk 02:21, 29 February 2008 (UTC)

[edit] Requesting color change in the world map

Hi, i'm new to editing Wikipedia and stuff so i apologise if i post this at the wrong place. I happen to be color blind and actually had to check the world map with paint shop to spot which countries had different shades of blue. Would be nice if a version with more different colors could be posted.. For ex not yellow/green, or blue/that other blue.. it really sucks being color blind ;( —Preceding unsigned comment added by 213.226.106.200 (talk) 03:54, 24 March 2008 (UTC)