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25 HZ är fel - USA (Elektrifiering/elektrisk drift)

av Olof W, Sunday, November 21, 2021, 22:09 (1232 dagar sedan) @ mormorsgruvan

Anledningen till att växelströmselektrifiering inte blev vanlig i USA, är att man gjorde det stora misstaget att välja frekvensen 25 Hz.

Det där får du gärna utveckla lite mera?

För PRR har jag för mig anledningen var den stora depressionen som sköt fram elektrifieringen så mycket att man hann utveckla diesellok som var ett billigare sätt att effektivisera långa järnvägar än elektrifiering.

/Olof

Hela tråden:

 

Time: 284
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Time: 1353
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: 1439
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: 3092

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