Model S

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Charging Stopped

Stored my 14 S 85 for the winter. I have it plugged into 120 to just maintain battery level.

Came out to find it completely dead. After a recharge to about 100 miles, the charging is stopping prematurely. Will run for an hour or two, then stops.

Running at 105 to 107 volts due to long wire run to outbuilding.

Does anyone know the minimum voltage? Would that cause chatter to stop?

Might try 240 at low amperage.

Comments

  • That's almost a 15% voltage drop. The chargin system senses that and cuts back. You can try a beefier extension cord (thicker wires/higher current rating) or 240V. The 240V charge is more efficient, even at low currents.
  • If the car was plugged in and battery was dead, how did recharge it?

    If the big battery was dead the 12v should also have been dead, was it?
  • @erw698_98196432, you wrote: “[I] might try 240 at low amperage,”and you describe a voltage drop to 105~107 volts.

    On this electrical supply, in the winter cold, your car cannot draw enough current to overcome charging ‘overhead’ which includes, but is not limited to powering the battery coolant heater which runs when necessary to prevent the battery array from dropping to potentially damaging temperatures. (In Summer, especially when charging, the AC system cools the array. There are also pumps, fans, and other ancillary equipment in this system, but you get it—in either scenario, it’s a large current draw, beyond what’s needed to charge the battery array.)

    For example: I’ve observed a total system 2880 watt draw (12 amps at 240 volts) when pre-warming the array for a cold weather charge. Drawing 12 amps at 107 volts, you’re getting less than half the wattage you may need. Furthermore, after sensing your 12.5% voltage drop, your car would most likely draw less than the 12 amps maximum continuous load allowed on a 15 amp, 120 volt circuit. In short, you’re starving your car of the current she needs to maintain charge in the cold.

    To store properly, connect to a 240 circuit; set the charging limit to 50%. Then your car has enough current available to maintain its battery array temperature—and its charge—as it was designed and programmed to do. A plugged-in Tesla is a happy Tesla.
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