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Anticipating Dual Charger with Wall Connector

Discussion in 'Model X: Battery & Charging' started by Vince Cobelo, Nov 20, 2015.

  1. Vince Cobelo

    Vince Cobelo Member

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    I have the electrician installing the NEMA 14-50 with 40 amp service/50 amp breaker in the coming weeks.

    My thinking is...just in case at some point in the future I want to add the dual charger and wall connector I would have him use the larger wire and conduit to satisfy 80 amp service/100 amp breaker. The run is short so the difference in cost is negligible. Question becomes does it make sense for me to go ahead and get the wall connector and have it installed even if the dual charger is not. Best I can tell it will still provide the 40 amp service it would just be permanent on the wall and then keep the other connector that comes with the car in the car.

    Thoughts?
     
  2. fwgmills

    fwgmills Member

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    If it were me, I would get the wall connector just for the convenience sake, plus the wall connector is cool looking. :D

    When I finally do pull the trigger and buy a Model X my plan is to put a HPWC on the right side (my side) of the garage. The breaker box is also on that wall. Then I will have a NEMA 14-50 outlet put on the left side of the garage so that I can still charge if I park on that side of the garage, or if I can get the wife into an EV and out of her Yukon. (I'll have to pry the keys out of her cold dead hand though. :p )

    It'll also have the benefit that if my brother ever brings his RV to my house, I'll have an outlet for him to use.
     
  3. FlasherZ

    FlasherZ Sig Model S + Sig Model X + Model 3 Resv

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    The convenience of the wall connector is unmatched, in my opinion and I would install it even if I had only a 30A circuit available rather than continually unwrapping/storing my UMC or buying a second UMC. I'd invest the extra $100 for the WC.

    There are two concerns you need to have as to whether or not you want to install it at the higher current: 1) can your current electrical service handle it, and 2) do you want to spend the money on higher installation costs. #2 is a personal decision, so I'll leave that outside the scope of the conversation. #1 is important, although most newer homes won't have problems with it. When you install the HPWC, regardless of whether your Model S or Model X is capable of or set to charge at 10, 40, 60, or 80A, you must use the breaker size the HPWC is configured for in the load calculations. If you have it set up for a 100A circuit, you must have 100A available in your load calculation. This is not subject to the "non-concurrent loads" rule found in code that lets you oversubscribe.

    If you can get past those, then by all means install it at the 100A setting and take advantage of it.
     
  4. Vince Cobelo

    Vince Cobelo Member

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    The installation cost difference is negligible. Really the difference is the cost between the 50 breaker and the 100 which would be partially offset by not having to get the NEMA 14-50. I too like the idea of having the permanent install. My garage is finished with wall to wall vinyl garage floor mat. I'm not quite getting the part of your comment about using the breaker size the HPWC is configured for. If I have a 80 amp circuit with the wall charger then the car will only accept as much current as it possibly can which would be 40 right?
     
  5. FlasherZ

    FlasherZ Sig Model S + Sig Model X + Model 3 Resv

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    The NEC requires you do a load calculation to determine whether you can add an additional load to an electrical system. When you do those calculations, you must use the appliance's installer-configured nameplate rating. This would be the DIP switch setting on the HPWC. If you install an HPWC at the 100A breaker setting, you must figure 100A (80A charging * 1.25 continuous load factor) into the load calculation, regardless of whether your particular Tesla can charge at 40A, 48A, 72A, or 80A, and regardless of your setting on the touchscreen. For example, people who have only 100A service in their home cannot legally configure their HPWC's with #2 conductors and the 80A setting, even if their car only charges at 40A maximum, because of this rule.

    In terms of installation cost, the difference between #3 and #6 is pretty significant with any distance from the panel, although you get a trade-off of not having to run a neutral if you choose HPWC. If it's close, no worries.

    I'd go with the wall connector regardless of any other constraints, because it's built a bit better and more convenient at home. As to what current you configure, that depends on the $$ for the wiring and the load calculations passing. Some jurisdictions are tougher on load calculations than others (some require that you submit your NEC article 220 load calculation as part of your permitting process).
     
  6. Lyon

    Lyon 2016 S P100DL, 2016 X P90D

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    ImageUploadedByTapatalk1448172577.520727.jpg
    We needed a second charging option. This is what I decided on.

    When the HPWC was $1500 it didn't make a lot of sense to me, now it makes no sense to buy a second UMC.
     
  7. Vince Cobelo

    Vince Cobelo Member

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    That looks nice. Is there are reason you mounted the HPWC below the connector holder? Just happened that way where the line fed through the house? Mine gets installed next week and without the car I'm trying to figure out how high and whether to put the HPWC above, blow or somehow staggered vertically...I have to use conduit because of the service level and because it is a block wall.
     
  8. Lyon

    Lyon 2016 S P100DL, 2016 X P90D

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    Sorry, just saw this. The decision to put it like that came about because I didn't have much horizontal space and because I wanted the cord coming out of the hpwc at about charge port level so as to maximize its reach. Let us know what you decide to do!
     
  9. modelx007

    modelx007 Member

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    It seems that I have an issue with enough power to my house... I have a model s ordered and waiting to configure a model x. I originally wanted 1 hpwc and 1 nema 14-50 but told I don't have enough service to support. I can only do 1 NEMA 14-50. Which poses an issue for when I eventually get the model x. Anyone else in this situation? I was told I would have to contact FPL in Florida and that would cost me about 10k to bring 400 amp service. So that isn't happening. Under the load calculations I can't even just install an hpwc because it needs 100 amp.
     
  10. MikeL

    MikeL some guy

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    #10 MikeL, Dec 22, 2015
    Last edited: Dec 22, 2015
    Hey Vince! In your OP you say "add the dual charger" just FYI as things now stand, that is not offered on the Model X
    You get the 42A or the 72A in your build, no upgrades. You CAN add the second charger (i think(?)) on any Model S originally configured w the single.

    I am planning on an HPWC in the garage, so that the UMC stays w the car (among other reasons) which requires a service upgrade at my house from the Oooold 100A to 200. Our electrician has quoted us a little over $2k tho, a far cry from $10k!

    reading back thru the thread, I guess I got the 10G$ # from Modelx007's post, not yours. :smile:
     
  11. FarmerDave

    FarmerDave Member

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    I have the same issue - 200 amp service but all-electric household with 4 ton heat pump on 40 amp breakers and auxiliary heat in air handler on 90 amp breakers. Add in the water heater, clothes dryer, etc. and it's possible to have high demand. My electrician installed a NEMA 14-50 outlet AND an HPWC configured at 40 amps on a 50 amp breaker. Obviously I can use the HPWC OR the 14-50 outlet, not both at the same time.

    I'd like to have added another 100 amp service, but with underground utilities it's just too costly.
     
  12. modelx007

    modelx007 Member

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    Problem is for me to do what u did I can't because it would never fly by permitting even if I say I will use one or the other...I am told they will go by code and not by what process I will use. So I will be stuck with the 1 nema 14-50 permitted setup until I make lots of money to give to fpl to bring in proper service. It's frustrating...I thought I was going worry free from gas to electric and now I have to deal with this. Not sure what I will do with charging when I get the model x... I could just see the disaster with 1 nema plug and two cars...honey you forgot to plug in your car to charge...honey that is your job to make sure our cars are properly charged....
     
  13. modelx007

    modelx007 Member

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    When I said 10k, that isn't what the electrician would charge for his work. That is what fpl power company would charge to bring in more power according to the electrician. I'm sure that may be a little high as I didn't actually contact FPL but even at 7k that is too high. Plus I then have to pay electrician his fees which probably would be another 2k+.
     
  14. MikeL

    MikeL some guy

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    around here, it is the power co.s responsibility to upgrade where necessary. The transformer on the pole that powers my house, & 4 others - I'm on the dead end - can either handle the load, or gets upgraded, free of charge. I then just pay $ for the extra use by kWh. The cost is built into everyone's bill, a "line charge". So I will pay Tesla for the hardware, the city for the permit, & the electrician for the work. Zero$ to the power Co. (?) as I understand it. :frown: Still a good chunk to add to a $128k bill, oh wait, they've had $5k for 3 years so it's "only" 123k :wink: about double the cumulative total of all the cars I have ever bought. & I'm pretty old!
    Go Tesla!
     
  15. FarmerDave

    FarmerDave Member

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    I understand your dilemma with permits, but if you find a way to have two outlets, just program the cars to charge serially using start and stop times. I will play it safe and only charge at night so I don't have to allow for clothes dryer, ovens, cooktop adding to the overall load (sigh, first world problems).
     
  16. MikeL

    MikeL some guy

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    I would just encourage all involved to focus on the goal - stop buying & burning gasoline. (The "best car ever made" thing comes as a bonus)
     
  17. ONELOVE

    ONELOVE New Member

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    I did what you are thinking of in anticipation of possibly getting a dual charger for my 70D. image.jpeg Seems dual drive would come with a dual charger yes? I didn't figure this out until I was deep into the process of getting my S. I keep the cord in my car and it's nice to have the wall mount with the Wall Connector. Plus if you let other dual charger S owners charge at your place, you can accomodate their needs. I'm planning to make mine available by listing myself on an app called PlugShare once I get my solar put on the house. I installed it toward front of garage for backing in or pulling in. About $1,200 by Tesla certified installer to install breaker box, install wall connecter, with permits et al.
     
  18. FlasherZ

    FlasherZ Sig Model S + Sig Model X + Model 3 Resv

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    The code actually gives you a provision to do just what FarmerDave is saying, in that case. 220.60 says "where it is unlikely that two or more noncoincident loads will be in use simultaneously, it shall be permissible to use only the largest load(s) that will be used at one time for calculating the load..." It doesn't have a lock-out/interlock requirement - just "unlikely".

    Now, with that said, it will be an inspector's determination. If you have an HPWC and a 14-50 for backup, you'll have an easier time convincing the inspector because the 14-50 is a backup, used in case of failure of the HPWC. But the inspector is less likely to accept it if there's a greater chance of the loads being drawn at the same time (e.g., you have cars plugged into both at the same time).

    That particular clause has no black-and-white rule, so your inspector will be the one determining what you can do.

    - - - Updated - - -

    Dual motor does not mean dual charger. On the Model S, the dual charger is an option that allows you to charge at up to 60 rated miles per hour/80A on a 240V/100A circuit with the HPWC, when compared to the standard, single-charger 30 rated miles per hour/40A on a 240V/50A circuit with the UMC or HPWC. It's an option that is installed only at the service center.

    Model X does not have an option for dual chargers - there is only a single charger capable of charging at up to 48A (60A circuit), but Tesla offers a hidden option for a charger that will charge at up to 72A (90A circuit).

    - - - Updated - - -

    The rules are different for every power company in every state and it's based on the regulations that states have adopted.

    In my case (a member-owned co-op), the power company will supply you with the meter pan and will be responsible for all of the cost of installing and upgrading transformers & conductors up to that point, and the homeowner is responsible for the cost of installing the meter pan and upgrading the service conductors from the pan to the service panel(s), along with any other inside upgrades required. (Note: the power company will only do this if the demand calculation seems reasonable... I can't get 600A/800A/etc. service just because I ask for it - I need to submit the load calculations.)

    Generally, the rules for investor-owned utilities are going to be tighter. They're going to try to pay the absolute minimum required by law for any upgrades. A good place to start is your public utilities commission - understand what the power companies are *required* to do first.
     
  19. modelx007

    modelx007 Member

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    Ok so here is where I'm at. I can only do 1 NEMA outlet because I'm maxed out. Another suggestion was to install a chargepoint which can charge two tesla's. So I can charge 1 at 40 amps and 2 at 20 each. Anyone install one of thesr?
     
  20. Lyon

    Lyon 2016 S P100DL, 2016 X P90D

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    Could you install two 14-50s but only wire/breaker each one to provide 20amps?
     

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