Caledonian Sleeper Class 92's

Discussion in 'Traction & Rolling Stock' started by Mag_seven, 17 May 2016.

  1. 59CosG95

    59CosG95 Established Member

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    Might it be something to do with the back EMF generated by the 92s being much larger and messier than those generated by the 390s?
    It may also be a problem caused by a lack of auto-transformer feeding across sections of the route (south of Bourne End Jn; Whitmore - Crewe - Weaver Jn; Euxton Jn - Preston - Lancaster - Carnforth; north of Great Strickland), although I'm not 100% certain on that.
    HS1 is auto-transformer fed throughout.
     
  2. hwl

    hwl Established Member

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    The rules on HS1 /tunnel feeding back as regards voltage parameters etc. may be different to NR's and the 92s were designed for the tunnels rules. It could be really simple...
    Some 92s have had equipment replaced by GBRf recently of course.
     
  3. themiller

    themiller Member

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    The 92s were also designed for use on the British electrified network where they would have spent the majority of their time.
     
  4. hwl

    hwl Established Member

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    But was regen allowed on BR network - regen parameters may have been set for tunnel etc with just rheostatic on BR?
     
  5. BRX

    BRX Established Member

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    Seems like a big old waste of energy not to have it working on NR - all just thrown away as heat. Not very helpful in the arguments of night train vs plane travel sustainability! But given the amount of diesel haulage that goes on under wires, it appears evident that there's not much incentive for energy efficiency built into NR's pricing structures.
     
  6. themiller

    themiller Member

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    Now there’s a question. Can anyone on here enlighten us lay people?
     
  7. themiller

    themiller Member

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    I’ve just spoken with a Virgin Pendolino driver who confirmed that they can regenerate on the whole of the routes where they operate! And before anyone mentions the north Wales coast, I mean under the wires!;)
    Spoke with a TPE driver who confirmed that 350s can regenerate on all of the routes that they operate on.
     
  8. TimboM

    TimboM Established Member

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    Given 92s took many months to obtain clearance to run under their own power on NR metals and are still to this day restricted to certain routes due to the legendry (or is that mythical?) EMF waves they give off and the need to draw the power of a small northern town, it's not a major surprise NR don't want them pumping electricity back into their 'heritage' overhead line equipment.
     
  9. 59CosG95

    59CosG95 Established Member

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    I think it might be a case of EMF interference generated - GTOs (as used by the 92s) tend to be messier than IGBTs (as used in more modern stock), and there's every likelihood that NR have said "if it can't regenerate on this part of this route, it can't regenerate anywhere on this route". Unless I'm mistaken, routes with track circuits are the main culprit for being interfered with, while axle counters seem to be OK.
    Perhaps maximum fault current may be "at fault" here? ;)
    Certainly stands to reason that ATF-enabled stretches of the WCML might be passable for it, but those stretches without it (and the same for the ECML) make it difficult to allow it throughout, so it's just easier to give a blanket ban rather than having lots of piecemeal sections of regen-capable OLE.
     
  10. TimboM

    TimboM Established Member

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    That may well be a reason - as far as I know you can't easily switch re-gen on or off in a 92 either (e.g. as it passed through different sections). There's different modes including "ET/AC" (EuroTunnel/HS1) and "BR/AC" for Network Rail. Assuming they do re-gen under the Tunnel/HS1 wires, this will most likely be activated as part of that ET/AC mode; and when in BR mode it's off.

    Incidentally the GBRf 92s now have IGBTs in place of GTOs, not that it would change any of the above.
     
  11. 43096

    43096 Established Member

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    I thought they now had IGBT auxiliary converters but retained their original GTO traction/main converters?
     
  12. TimboM

    TimboM Established Member

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    I’m pretty sure you’re correct. I was scrimping on detail!
     
  13. 59CosG95

    59CosG95 Established Member

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  14. TimboM

    TimboM Established Member

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    Overhauled 92032 leaving Crewe for Wembley on Sunday (ahead of moving to Dollands Moor yesterday):

     
  15. 43096

    43096 Established Member

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    Interesting that it hasn’t received the replacement headlights that those previously done have.
     

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