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Install a 40 or 50 amp line for NEMA 14-50 outlet?

Discussion in 'Model X: Battery & Charging' started by Greg, Mar 11, 2016.

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  1. Greg

    Greg Member

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    My guess is that this topic has been discusses already, but I can't find it! I have a 90D Model X on order and am preparing my garage. I did not move forward with the 72 amp charger on the X opting for the standard 48 amp charger. I called my DS and he said that a NEMA 14-50 can only deliver 40 amps. This did not sound right to me and it seems like it would not take advantage of the faster on board charger the X has over the S, but what do I know so I said thanks and hung up the phone. Next I had an electrician come by and look at my breaker panel and give me a quote for the installation. He asked me if I wanted a 40 or 50 amps to the NEMA 14-50 outlet. I'd love to go with 50 amps assuming that I would be able to charge 20% faster. Is this the correct thing to do or was my DS correct?
     
  2. K-MTG

    K-MTG Sunshade Captain of TMC

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    The Model X is 48 Amps however the include wall connector can only deliver 40 Amps. By installing the HPWC you can use the full 48 Amps.
     
  3. KJD

    KJD Member

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  4. jerry33

    jerry33 S85 - VIN:P05130 - 3/2/13

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    You would need an HPWC to charge at 48 amps. Note that the HPWC has dip switches to control the amps used, so it doesn't need to have the fully 100 amp breaker and wiring if the goal is to charge at 48 amps.

    Because charging an EV is considered to be a continuous load, the charging rate can only be 80% of the breaker size (assumes standard type breaker).
     
  5. Greg

    Greg Member

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    OK, I understand that you need a 60 amp breaker to make this work and it was mentioned that you need a HPWC as well. Is it possible to use a NEMA 14-60 outlet with a 60 amp breaker and leverage the 48 amp charger?
     
  6. FlasherZ

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

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    #6 FlasherZ, Mar 11, 2016
    Last edited: Mar 12, 2016
    No. The UMC ships only with a NEMA 14-50 (RV or range receptacle) adapter (EDIT: and a 5-15 120V adapter, but that's not what you're talking about). No 14-60 adapter is offered. 14-60 receptacles are not really found in the wild, and the UMC is rated only for a 40A charging rate (50A circuit).

    To use the full 48A charging rate, you will require a Tesla Wall Connector ($750 + installation) or another J1772 compliant EVSE that can supply 48A or more. Technically, you *could* find a piece of J1772 compliant EVSE and attach a 14-60 plug onto it, also installing a 14-60 receptacle, but at that point you may as well just hardwire it.
     
  7. Greg

    Greg Member

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    Thanks FlasherZ. So now I need to decide if I will stick with 40 amp charging or pay up for the HPWC for the 20% increase in juice. I'll most likely stick with the NEMA 14-50. I just figured since I'm installing everything now I should try and go big! In reality the X only has 257 mile range so even if I charged it with 1 rated mile left it will only take 10 1/2 hours to fully charge and 8 1/2 hours to charge to 80%. Either way it works with a normal nightly charge routine starting at 10 or 11 at night. As well, the most common situation is to charge it when there is 30-60% of juice remaining so it will charge even quicker.
     
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  8. TexasEV

    TexasEV Active Member

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    No, you should plug it in when you get home every night regardless of the state of charge, and let the battery management system manage the battery. Remember, "A connected Model S is a happy Model S" -- and that's true for the Model X too.
     
  9. SW2Fiddler

    SW2Fiddler Bannd Member

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    #9 SW2Fiddler, Mar 12, 2016
    Last edited: Mar 12, 2016
    This is how I think as well. But this thinking would have me choosing 72A installed (and a HPWC to get the benefit).

    edit. I happily used a NEMA 14-50 for a year, then a HPWC for a year. I do like the convenience of the permanent cable of the HPWC. Less fiddling around and the UMC just stays in the trunk.
     
  10. FlasherZ

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

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    But I thought that's what you like to do?!
     
  11. K-MTG

    K-MTG Sunshade Captain of TMC

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    I want to install a HPWC but would like to know if my panel has enough room (I have a 40 AMP EVSE for my ELR but it only charges at 16 AMPS), here is the detail:

    200 AMP service from SCE
    Main Panel: 225 AMPS
    Sub Panel: 70 AMP

    Does my panel have enough room for a 240V 80 AMP Tesla Wall Connector (100 AMP breaker needed). If not, how many AMP's are available?

    My average load is 2 kWh
     

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  12. FlasherZ

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

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    Unfortunately, I can't even take a stab at the load calculations based on the information you gave me. I can probably guess based on what I see in the main panel, but I don't know what's in your subpanel. I'd need to know the square footage of your home as well.

    From what I see in your main panel, I'm going to venture a guess that load calculations aren't going to work in your favor with only 200A service, with 2 A/C units plus kitchen SABC's + disp/dish + laundry + spa tub...

    Then you'll have another problem -- there is just no room in that panel. There are no tandem options for 100A breakers; like your 70A breaker, you'd need 2 full 1" spaces to place a 100A breaker there, which means moving multiple circuits to a new panel (or replacing that panel).
     
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  13. K-MTG

    K-MTG Sunshade Captain of TMC

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    Thank you very much! I have the photos of the sub 70 AMP panel attached. My house is approximately 4,800 square feet.

    On my Model X I went with the standard 48 AMP charger, however I want to wire the HPWC for 80 AMPS in order to future proof my install.

    If my panel is full, what is the max amperage I can use without purchasing a new one? How much does a new panel cost? I also plan on purchasing the power wall in the future.

    Here are some of the large loads on my panel:
    1) Solar is 4.85 kw
    2) I have not idea what F.A.U is
    3) Kitchen (Microwave, Dishwasher, Oven) (Range is GAS, Heat is GAS)
    4) I have two big AC's and one small AC
    5) I don't have a spa so I don't know what the spa is for
    6) My dryer is gas so laundry is not used.
    7) Cadillac ELR (16 AMPS)

    It's unlikely I would even go over 150 AMPS at night since the only two draws when my car would charge between 10PM - 8 AM are the cars charging themselves. Unlikely anything else would be running.

    Since my panel is full, is it possible to install the HPWC with 100 AMP wiring but with a lower AMP breaker so in the future when I upgrade my panel I would simply need to replace the breaker?

    Thanks Again!
     

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  14. chargeshare

    chargeshare Member

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    FAU - Forced Air Unit?
     
  15. K-MTG

    K-MTG Sunshade Captain of TMC

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    That's right, I have a gas force air heater but that is never used in SoCal. Btw the HPWC is no longer available at shop.teslamotors.com, is a new one on the way? When I called service about it he was telling me not to get the HPWC and stick with the 240V outlet and the UMC
     
  16. FlasherZ

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

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    Do you have a whirlpool tub in the master bath? Most of the time you use 1-2 circuits for jets and/or heater. That's typically what "spa" is for. New 2014 rules require us to treat a washer receptacle as a load, doesn't just include the dryer circuit.

    4800 square feet is considered @ 3 VA or 3 W per sq ft... 2 kitchen small appliance circuits plus laundry must be figured at 1,500 VA per circuit or 4,500 VA. 4800 * 3 = 14,400 + 4,500 = 18,900 VA. First 3,000 VA @ 100%; remainder at 35%. So 8,565 VA for lighting & receptacles, or 36A. Good news is that it appears all of your subpanel is covered by the general lighting & receptacle rules. Fixed appliances (dishwasher, disposal, microwave, etc.) are figured at 75% of their nameplate wattage ratings - figure about 6 kW @ 75% = 19A or so. You must cover your oven at 80% of its rating. A 40A circuit is generally a 6-8 kW unit, so that adds 20A to your load. A/C + blowers must be considered at their full nameplate ratings. I'm guessing your larger A/C unit will count for 15-20A. So 100A for HPWC + 36A for lighting/receptacles + 19A for fixed appliances + 20A for oven + 20A for big A/C = 195A, and we haven't figured in your smaller A/C units or other fixed loads in there.

    I'm guessing you might be able to get an 80A HPWC rating to work in the figures.

    The biggest problem you're going to have is that your panels are both completely full. You only have room to create one more 120V circuit in the upper-right breaker of the subpanel. I'm not aware of any type BR half-height AFCI's. There's no room for a new 240V breaker in either of your panels.

    Typical panel changes and service upgrades typically start at $2,500 and varies upward with complexity. It also depends upon what your share will be with the power company. With my co-op, the power company provides all conductors and equipment up to the meter pan, you supply everything internally. With some power companies, you'll be responsible for buying new meter pans and paying the power company for the upgrade.
     
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  17. FlasherZ

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

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    I wouldn't be surprised. The existing HPWC doesn't have a 60A breaker setting any more for Model X, it really needs one. Also, if you look closely at the summon video that Tesla posted, you can see a different HPWC in the background...
     
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  18. K-MTG

    K-MTG Sunshade Captain of TMC

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    Thanks again! No, I only have a standard bath tub. Will shut off the spa breaker and see if anything shuts down.

    Since my service would support the 80A for the HPWC, what is the cheapest option to get the HPWC installed? Installing a sub panel? How much do those cost? Would this pose a problem since I also plan on getting the powerwall?

    Thanks!
     
  19. FlasherZ

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

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    I'm not sure about the different installation models for the Powerwall; whether its inverter and charge controller would be a replacement for your existing grid-tie inverter or not. If it's a replacement, you'll likely use the same breaker you currently use for solar PV.

    I guess I should have asked a question -- will you be replacing the ELR? Or do you plan for that to be side-by-side with the Tesla? When I did rough load calcs for you, I made an assumption that your existing EVSE would be de-energized, but I probably shouldn't have made that assumption. If you need that existing EVSE, then its load would likely put you over the top for a 200A circuit -- unless you configure the cars to charge at different times and your inspector will allow you to use the non-coincident loads rule. That's a rule that says you don't have to count the smaller of the 2 EVSE loads if it is "unlikely" that both would be charging at once. Some inspectors will allow you to make that claim, others won't and want an enforced lock-out to prevent them from charging at the same time. If you can't use that, you're definitely over and will need a service upgrade.

    As for panel room: if you can de-energize that EVSE, I would move the circuit for A/C #2 that shares w/ the spa breaker up a couple of slots to take the breaker connections currently used by the EVSE. Then I'd pull that breaker that says spa + AC/2 and replace it with an 80A dual-pole for the HPWC.

    If you can't de-energize that EVSE, then you're going to have to do something else. You could install a second subpanel and move a few circuits over to it; you could look at upgrading your service to 400A and installing a new 200A panel off the base of the meter, not touching anything you currently have; you could replace your subpanel with something larger and upgrade the conductors and breaker serving it from the primary panel to 125A or so... At that point there are a lot of different variables.
     
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  20. K-MTG

    K-MTG Sunshade Captain of TMC

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    Thank you!
    Yes, I will keep the ELR. What is the typical cost for a sub panel + install? Regarding the power wall, I assumed a backup panel would be needed for critical circuits in a event of a power outage?

    I could set both cars to charge at different times, I have 10 hours on the super off peak rate. The ELR takes four hours to charge and I could use the remaining 6 for the Model X.
     

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