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Psi Puzzle

Discussion in 'PC Discussion' started by breblimator, Jun 27, 2021.

  1. breblimator

    breblimator Well-Known Member

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    I always knew the HUD was a real pandora's box. Something tempted me to check something...
    Initial reduction. Yes, I'm going to fight until the end! :D

    PSI-PUZZLE.png

    What is SimuGraph for when this is how data presentation looks like?
    PS I would like to live in blissful ignorance... Please put me back in the Matrix /o\
     
    Last edited: Jun 27, 2021
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  2. Anthony Pecoraro

    Anthony Pecoraro Well-Known Member

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    What are you referring to?
     
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  3. breblimator

    breblimator Well-Known Member

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    gauges psi vs hud psi :) 6 vs ~9 (a reduction value)

    EDIT

    I recently praised the Dash-8 for its improved initial reduction value - now I have doubts :|
     
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  4. JustWentSouth

    JustWentSouth Well-Known Member

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    I feel like the initial reduction on the Dash-8 is not as strong as the 4400. It seems much easier to me to find a good blended brake setting on the Dash-8 than it is on the 4400.

    My favorite is the lapped brake of the F7 - my initial set can be as soft as I want!
     
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  5. breblimator

    breblimator Well-Known Member

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    I have similar feelings, but I don't like such a mess :)
     
  6. Lamplight

    Lamplight Well-Known Member

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    This is strange. Did you happen to check the EoTD after a sufficient amount of time?
     
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  7. breblimator

    breblimator Well-Known Member

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    I haven't checked. Another variable. And without it, we can see something is wrong :)
     
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  8. Lamplight

    Lamplight Well-Known Member

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    Agreed. I'll try to check it out as well when I've got time.
     
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  9. Lamplight

    Lamplight Well-Known Member

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    My results:
    C5406EB6-7C69-487E-A8A7-4890E2D67F44.jpeg
    42DB1675-E100-474C-A1A4-85509272C510.jpeg
    EC9A7862-B681-4EB6-9146-BA50D1EC44E8.jpeg
    All photos taken after sufficient time had passed for the brake pipe to adjust.

    HUD: 81 psi
    Loco gauge: just under 84 psi
    EoTD: 81 psi

    With HUD and EoTD agreeing, I think the TSW standard ~ 9 psi reduction is in effect. Especially knowing that the loco gauges can be inaccurate in TSW (looking at you, Br 363).

    With a different train, I also looked at the gauges of a trailing SD40-2 - its in-cab gauges also claimed an initial reduction of ~ 9 psi, but I didn‘t get pictures of that. The case seems pretty clear unfortunately.
     
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  10. breblimator

    breblimator Well-Known Member

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    I believe it is effective 6 PSI. But there is no doubt that something is wrong :)
    PS I will do a test vs AC4400 in my free time \o/
     
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  11. wxtr7

    wxtr7 Well-Known Member

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    Same for me. The AC4400 is the only loco I have trouble controlling downhill. Every other one works just fine. My recent run down SPG required full dynamics and full service air to get the train to just slow down. (it was a coal train with AC4400 & SD40, no DPUs, which is probably a little underpowered, but thinking back to past SPG runs even with all AC4400s I still have problems). Oddly, after I saved and came back, it seemed to handle better and more controlled. But the dash 8, and the F7 on CRR's hills I have no problem finding a balance and managing down hill, so IDK.
     
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  12. Jamy

    Jamy Active Member

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    Thank god i still live in the Matrix
     
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  13. TheShotte

    TheShotte Well-Known Member

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    To be honest, I have stopped paying attention to the value inconsistencies a long, long time ago. HUD will say 15mph, speedometer will say 14, HUD PSi will be 0.3, gauges will say 3, etc. I simply chalk it up to instrument calibration being ever so slightly off. :)
     
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