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Likströmsbana (Elektrifiering/elektrisk drift)

av Per Ljungberg, Friday, November 19, 2021, 12:56 (1196 dagar sedan) @ Christer Brimalm

På de filmer som visades från höghastighetskörningen såg man stora ljusbågar vid strömavtagarna i samband med bygelstudsar. Eftersom likström inte har nollgenomgångar (som växelström har) så slocknar inte ljusbågen utan dras ut tills strömavtagaren åter får kontakt med kontaktledningen. Förmodligen blev det därför brännskador på kontaktledning och strömavtagare.

Hela tråden:

 

Time: 235
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 pid = 0 AND (mlf2_akismet_rating.spam = 0 AND mlf2_b8_rating.spam = 0) AND 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)

Time: 1107
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: 1235
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: 2619