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Perdix AI Average SAC

Discussion in 'Shearwater Research' started by stalefish, May 15, 2019.

  1. stalefish

    stalefish Angel Fish

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    Does anyone know how the average sac is calculated for a dive where the diver switches to a tank without a TX? For example, a dive conducted with a TX on your main tank(s), but then you switch to a deco tank that doesn't have a TX.

    Obviously the Perdix keeps track of the SAC for the entire dive, but once you switch to the deco bottle, the SAC will drop to zero. Is the "Average SAC" displayed in the subsequent log calculated based on all the values recorded during the dive or just the values that are not zero?
     
  2. Mike1967

    Mike1967 Manta Ray

    # of Dives: 50 - 99
    Location: Victoria, Australia
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    The whole dive. Even if you have two TXs it only calculates on one of them, your choice which one.
     
  3. stalefish

    stalefish Angel Fish

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    Seems like it would be more accurate if it threw away the samples that read "0". For an hour dive, there should be ~ 360 samples, if 180 of those are "0" then you just halved your Average SAC rate.
     
  4. IncreaseMyT

    IncreaseMyT Banned

    # of Dives: 100 - 199
    Location: Naples, FL
    1,235
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    Are you noticing a change in SAC rate when switching tanks? I am not.
     
  5. stalefish

    stalefish Angel Fish

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    Yes it is significantly lower on dives where I'm switching tanks. Sometimes by as much as half.
     
  6. IncreaseMyT

    IncreaseMyT Banned

    # of Dives: 100 - 199
    Location: Naples, FL
    1,235
    314
    83
    Oh sorry, I was talking about using different size tanks on different dives.
     

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