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25 HZ är fel (Elektrifiering/elektrisk drift)

av Thomas K Ohlsson, Sunday, November 21, 2021, 16:13 (1108 dagar sedan) @ mormorsgruvan

Anledningen till att växelströmselektrifiering inte blev vanlig i USA, är att man gjorde det stora misstaget att välja frekvensen 25 Hz.
Östergötlandsjärnvägarna samt NKlJ använde 25 Hz men där var motorstyrkan inte så stor, därför gick det utan problem.

Varför är 25 Hz 'fel', medan 16,7 och 50 Hz tydligen är rätt?

undrar
Thomas K Ohlsson

Hela tråden:

 

Time: 248
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Time: 1086
SELECT COUNT(*) FROM mlf2_entries LEFT JOIN mlf2_akismet_rating ON mlf2_akismet_rating.eid = mlf2_entries.id LEFT JOIN mlf2_b8_rating ON mlf2_b8_rating.eid = mlf2_entries.id WHERE (mlf2_akismet_rating.spam = 1 OR mlf2_b8_rating.spam = 1)
Time: 1329
SELECT COUNT(*) FROM mlf2_entries LEFT JOIN mlf2_akismet_rating ON mlf2_akismet_rating.eid = mlf2_entries.id LEFT JOIN mlf2_b8_rating ON mlf2_b8_rating.eid = mlf2_entries.id WHERE category IN (0, 4, 5, 6, 7, 8, 9, 25, 14, 23, 19, 22, 24, 10, 21, 11, 12, 13, 15, 16, 26, 18, 20, 27) AND (mlf2_akismet_rating.spam = 0 AND mlf2_b8_rating.spam = 0)

Total time: 2673