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P.E.M. Temperature at which Power Limit comes on?

Discussion in 'Roadster' started by sethr, Apr 21, 2016.

  1. sethr

    sethr CPO Roadster #1089

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    Hi all - does anyone know what P.E.M. temperature initiates power limiting? The last couple of days power limiting has come on rather easily (moderate driving in mild (70 degrees) weather). When I get home, with the power limit light still illuminated, the VDS shows a temp. of only 37 degrees C. I seem to remember the limit was 60 - something degrees? Also, the fans do not seem as loud as usual, but that may be my imagination. Anyone have any input? TIA!
     
  2. dhrivnak

    dhrivnak Active Member

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    Something sounds wrong as it only happened to me once when it was just over 100 outside.
     
  3. Stefan T

    Stefan T Member

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    The Power limit comes apprx 60C in the pem
     
  4. sethr

    sethr CPO Roadster #1089

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    It turns out (according to Tesla), that the temperature shown is actually an average of three temperatures, one for each section of the PEM, (and one was above 60, setting off the power limiting). I go in for my annual on Monday, two weeks earlier than I'd scheduled. Interesting tidbit of info.
     
  5. NigelM

    NigelM Recovering Member

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    If you go into the service FW settings you can set your VDS to show actual temps of the three different components.
     
  6. wiztecy

    wiztecy Active Member

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    Are you sure you're not confusing the 3 individual components with 3 temperature points on a single component? In your case you're talking about the motor, PEM, and battery correct? Sethr is talking about 3 unique temp pickup locations on the PEM itself that then is averaged together to come up with the finalized PEM temp. I don't believe there's anywhere in diags that displays those 3 points, at least on the 1.5 and I've poked around on the 2.x's as well.
     
  7. NigelM

    NigelM Recovering Member

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    Correct. I'm thinking it's at least much more accurate that the colored bars.
     

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