Amperage for Wall Connector

Discussion in 'Charging, Infrastructure & Efficiency' started by stebuu, Oct 2, 2017.

  1. stebuu

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    I am getting ready to install my Wall Connector in preparation for my Model 3, and I had a couple questions:

    1) What should I set the internal amperage inside the wall connector to? I am planning on it being on a 100 amp circuit to future-proof, but I know that my model 3 can only handle 60A. I would assume that the Wall Connector would adjust the current flow and that setting the wall connector to the full 100A would be safe, but I don't like to assume.

    2) Would it be better for the battery to set the wall charger to a lower amperage, say 40A? I am planning on keeping the battery at 80% charge almost all the time, and I would like to get a decade out of my model 3, so I'm willing to baby the battery a bit.
     
  2. Kizzy

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    48 amps is the max the long range battery charger will accept. The car can also be set to a lower max amperage it will charge at from a wall charger. The wall charger will charge your car at the max that it will accept.

    If you plan on adding a second wall charger for another car (in daisy chain fashion), I believe the higher amperage can be split between them to maximize charge rate between cars.
     
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  3. BigBri

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    100 amps isn't a terrible idea but you can always get a new breaker down the line. If you want to use 48 amp then yeah depending on your electrical code then yeah you'd need a 60 amp as you need 20% buffer. That also depends on what EVSE you end up choosing. As for the charge speed you're not going to do anything to the battery by running the charge rate at the full 48. Only suggestion there is just supercharge when you need it. It's a bit stressful on the battery and cooling. Especially with an air cooled battery like the Leaf.
     
  4. TheStig

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    My understanding is the model 3 in standard battery charges at 32amps, the long range battery 40amps from the included UMC or the Tesla Wall connector. Same rates would apply to using J1772 and the included adapter. Only The model S and X can get to 48amps off the Wall connector (Or 80 amps if ordered with the dual charger option).

    When installing power for most any EV Tesla or other a 50amp breaker feeding 6 gauge wire to a 14-50 receptacle (outlet) is all you really need. The UMC that is included with all Tesla’s will plug right in, and any other J1772 EVSE up to 50 Amps. Anything bigger must be hardwired.
     
  5. garsh

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  6. TheStig

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    I read that shorty after posting. Didn’t the press kit or delivery event slides show 32 and 40 amp for the respective battery packs? We’ll take the 48 amp limit for those who go all out with the Wall connector on a 60A breaker at least on the extended battery. Standard battery remains a mystery for now.
     
  7. garsh

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    Yes. In particular, the presskit says:
    • Short Range: Home charging rate: 30 miles of range per hour (240V outlet, 32A)
    • Long Range: Home charging rate: 37 miles of range per hour (240V outlet, 40A)
    Given that the presskit mentions a 240v outlet, we can assume that they're talking about charging with a Mobile Connector instead of a Wall Connector. The two rates would appear to correspond to the two different kinds of UMC's that @RiggerJon received with his car.
     
  8. Model34mePlease

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    Why do you think those charge rates are with the UMC. The Tesla store seems to indicate the new UMC is supplied with the Model 3 and is limited to 32A.
     
  9. garsh

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    We've already seen that the car's built-in charger goes up to 48 amps, so it's not the car. And the presskit mentions a 240v outlet. And we know the new MC only goes to 32 amps.
    My guess is that the new one will be delivered with short range cars, while long range cars will get the old one that goes to 40 amps.
     
  10. Impatient

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    To answer the OP's original question: The car is irrelevant for your specific question. If the wall charger is being installed on a 100-amp circuit, you must set the internal wall charger setting to 100 amps.*

    What you then draw from the car is an entirely different matter and is wholly based upon the settings that you make within the car.

    IOW, the dial inside the wall charger is not answering the question "What amperage is my car going to want from this charger?" The dial inside the charger answers the question "What is the maximum amperage available from the electrical panel to the charger?"

    *This, of course, assumes that your panel has the capacity to deliver 100 amps to the charger and that the wiring between the two is suitable

    **I guess you could set a lower charge limit using the internal dial on the charger, but if you're putting the charger on a 100-amp circuit, why would you cripple the charger via its settings? The car can't draw more than the car can draw.
     
  11. VijayG

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    I am planning to get NEMA 14-50 outlet (with 6 gauge wiring (supports both 50\60 amps) installed in my Garage for my Model 3 (Long Range ) . I am trying to figure out which circuit breaker to install 50 amp or 60 amp. I was under impression that 60 amp would give more charging rate than 50 amp with Mobile Connector that comes with the car as the on board charger capacity is rated at 48 amp/11.5 kw & only 60 amp breaker can provide 48 amp continuous output.

    1) Can The Mobile Connector (Gen 2) draw 48 amp from NEMA 14-50 with 6 gauge wire & 60 amp breaker.

    Can someone please help me understand this or suggest on which one should I buy (50 amp\60 amp breaker).
    I dont' have plans to get Wall charger yet. I will be using Mobile Charger initially & see if it suffice my driving needs.

    It is little bit confusing to me, I read some articles on Tesla website. My understanding based on the article, even for the wall charger only a 60 amp breaker would provide 48 amp charging rate.

    The mobile Connector's max capacity says: 32 amps maximum, controlled by appr NEMA adapter.
    https://www.tesla.com/support/home-charging-installation#charge-port
    Vehicle battery optionOn-board charger capacity (current/power)
    Model 3 Standard battery32 amp / 7.7 kW
    Model 3 Long Range battery
    Model S or Model X with 75 kWh battery48 amp / 11.5 kW
     
  12. Kizzy

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    The Gen 2 UMC can only draw 32amps max (as you've read) and won't draw more than that.

    If you're going to install a NEMA 14-50, a 50amp breaker would be appropriate. Installing a 60amp breaker would probably violate electrical codes.

    However, if you instead installed a Wall Connector, you could make use of up to 48amps with the 60amp breaker.
     
  13. eprosenx

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    6 AWG wire will support 50 amps in nearly all cases (as long as you don't have other temperature or wire fill reasons to derate it). It can support 60 amps if it is in conduit and the terminals on both ends are rated for 75c. Now with that being said DO NOT INSTALL A 60 AMP BREAKER ON A 14-50 Receptacle. This is violation of NEC and could be dangerous. a 14-50 can be installed on a 50 amp or less breaker. (a full 50a breaker with 50a rated wire is generally recommended)

    Yes, the Model 3 LR can accept up to 48 amps which requires a 60a circuit (80% derate since the car is a continuous load).

    The UMC that comes with the car and can plug into a 14-50 can only draw 32 amps max. So it can either go on a 40a or a 50a circuit (using the included NEMA 14-50 adapter).

    So to answer your question, NO the mobile connector can not draw 48 amps. First, it is limited to 32, and second, the NEMA 14-50 is not good for any more than 40 amps continuous (50 amps non-continuous).

    If you ran 6 AWG NM cable (Romex) then you can't use it at 60a since you are required to use the 60c rating of the conductors.

    P.S. FWIW, you responded to a thread from last year. ;-)
     
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  14. VijayG

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    Thank you :)
     
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