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Causes for 75% reduction in HPWC charging level

Discussion in 'Model S: Battery & Charging' started by SDRick, Jul 15, 2016.

  1. SDRick

    SDRick Member

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    My automatic overnight charging level set for 48 A. I noticed last night's charging cycle was reduced to 16 A for the whole period. What would be the cause of such a significant reduction in charge rate?
     
  2. mikeash

    mikeash Active Member

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    This can happen if you don't fully seat the plug in the car's charge port. There's a certain point where it's in far enough to make solid contact, but not enough for the car to be able to lock the plug in the port. In that case, the car will still charge, but only at 16A. (Presumably that's the maximum safe level in a situation where the plug could be pulled out at any moment without warning.) When this happens, the charge port will be orange rather than green.
     
    • Informative x 1
  3. SDRick

    SDRick Member

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    I thought it may be something along those lines although best I remember, the charge port was blue after I plugged in and that it would be good to go for 48 A.
     
  4. Don85D

    Don85D Member

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    I believe that the car senses voltage drop while slowly increasing current to the requested level. If it sees a drop is stops taking more current. You may have a bad connection in the circuit to the car.
     
  5. mikeash

    mikeash Active Member

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    Blue indicates that it sees the plug and is starting to charge. It then changes to green to indicate that everything is good, orange to indicate that the plug isn't latched, or red to indicate an outright error. If you looked away when it was still blue then it could have then changed to orange without you noticing, so I'd bet that was it. If you want to see it in action, you can put the plug in partway on purpose to trigger it.
     

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