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NEMA 14-50 Installation - should I go ahead and get two?

Discussion in 'Model S: Battery & Charging' started by jesseasi, Jul 31, 2014.

  1. jesseasi

    jesseasi Member

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    Ordered Model S P85 - delivery is in September.

    Had an electrician come over today and he is working up a quote - seems to be making it really complicated...but we will see when I get the official quote.

    Since I am going to get one Nema 14-50 installed - should I just go ahead and get two? I could easily see ourselves buying a Model III or maybe even a Model X down the road. If I am going to pay to get one installed - should I just go ahead and get two?

    Or could we install two outlets on one circuit? Would it blow the circuit if we hooked up two cars at the same time?

    Any tips or suggestion in this matter would be appreciated.
     
  2. tiblot

    tiblot Member

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    You can't put two 240's on one breaker. Each will require its own breaker. Most electrical code will require that ...

    As for the whole house, it depends on your main breaker. Do you have 200 amp service to your house? What other load do you have?
     
  3. teslasguy

    teslasguy MSP P#1117

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    I ran a 100 amp line to a subpanel in my garage for exactly that reason. Can easily run two 14-50 outlets off this subpanel now. I have 400 amp service to the house.
     
  4. jcaspar

    jcaspar Member

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    When I wired my garage I put in a 100 amp sub panel with 2 14-50s, one on each side of the garage. As the labor was free (me), it still wasn't too bad of an expense (though 2-3 Romex is expensive and hard to work with!). I did this so when I got a dedicated EV meter for better rates, I could run both outlets off the meter. As I already had a 14-50 so actually that makes 3! Can't have too many...
    Also have a 400 Amp service to the house with 200amp, 100amp(EV) and 90 amp(Shed) sub panels.
     
  5. gavine

    gavine Petrol Head turned EV Enthusiast

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    You can dial-back the charge rate down to 20 amps on each car so you could theoretically charge both cars at the same time but at half power each. I'm not sure if this complies with electrical codes though.
     
  6. tezco

    tezco Sig P85

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    You can also use the charging timers to separate the two charging loads.
     
  7. TexasEV

    TexasEV Active Member

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    It sounds like your second electric car is at least a few years away. If it was me I'd just install the one 14-50 you need now but consider having the electrician run conduit for a future second circuit if needed. If you do get a second Tesla, you might not even need a second circuit if you can alternate charging cars each night, depending on how much you drive.
     
  8. bonnie

    bonnie Oil is for sissies.

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    You're going to find that you make new friends that drive electric cars. And they'll appreciate a place to plug in. :) Seriously, I had two plugs available (70 amp, Roadster|Model S & 40 amp 14-50 |J1772) during a recent bbq and both were going non-stop. The portable J1772 was on loan from Clipper Creek and was heavily used by a couple Leaf drivers that stopped by - I'm thinking I need something like that here for the future. And I may put in another 70amp HPC so that I have three spots total to charge. (But then, I like to throw parties.)
     
  9. gavine

    gavine Petrol Head turned EV Enthusiast

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    i thought the same thing when I decided to go with one 14-50. When we get our Model X, we will either take turns charging at night, or just charge one in the early evening and the other overnight. That would give us each more than enough juice to get by.
     
  10. linkster

    linkster Member

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    +80

    To "future-proof" and if load calcs permit, you may want to consider a 14-50 and an HPWC.
     
  11. wamochi

    wamochi Member

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    i kind of wish we had. not that we have plans right now for a second Tesla or EV, but it's in the back of our minds. we had solar installed in Nov 2013 and the run from the garage roof (where the panels are located) to the main electrical panel is over 200ft, meaning $$$ for running conduit through the attic space and back to that panel. we didn't have an order for a Model S at the time but thought there was a good likelihood we would be adding an EV when our hybrid lease came due this year. we saved a ton of money by having the PV and EV outlet permitted together and the work done by the solar crew. placing and pulling all that conduit through the attic was not easy, and would have easily cost me $1500-$2000+ i think as a standalone job. and this is just for a 240v NEMA 14-50.

    now in hindsight i wish we would have done the run for an 80 amp HPWC or a second NEMA 14-50 in the garage in the event we add another EV. i don't look forward to having the work done again, and i know it won't be cheap the second time around. the first time was a no brainer because they were already placing conduit for the PV so it was just a matter of pulling a second flex conduit for the outlet.

    so yes, if you think you are likely to become a two-EV household, i would definitely pony up for two outlets now, especially if you have a difficult conduit run like me. if your panel is just outside your garage, i probably wouldn't bother. but for something like ours, we did need a permit.
     
  12. TonyWilliams

    TonyWilliams Active Member

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    I would put a second 14-50 outside for your EV friends (and any motor home driving friends). Then, when Model X/3 arrives, you'll be able to charge that right away until you get the garage equipped they way you want it.

    When I had a house "EV party" last August, I stole power from both my neighbors house and my house with a dedicated 50 amp breaker and 75 foot lengths of 6/3 SOOW cable with a NEMA 14-50R on the end. That's in addition to the other three dedicated 50 amp outlets in my garage, plus 40 amp Clipper Creek. I think we were charging 5 cars at once most of the time.



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  13. dsm363

    dsm363 Roadster + Sig Model S

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    If you have room it's a good idea. If you have a two car garage and both cars pull straight in the one on left side towards garage door and one in middle between both cars. Or second one can go on right wall near garage door and cable runs behind car on right. As said above consider running wire thick enough for HPWC so you could change your mind down the road.
     
  14. danzig

    danzig New Member

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    It does sound like a good idea to get, if you know for sure in the near future you are going to be purchasing another. That being said I would wait until you get the actual quote 1st.
     
  15. Solarguy

    Solarguy Member

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    #15 Solarguy, Aug 1, 2014
    Last edited: Aug 5, 2014
    I had a similar situation as the OP and this is what I went with. Since I have so much time on my hands (waiting for the Model S and even longer for the Model X) my OCD kicked into high gear. I just finished installing two HPWC's to supplement the two 14-50 outlets in the garages. I was able to source both HPWC's for $900 each from two people selling them on eBay, new in the box, because they bought them with their Model S order and then decided not to install them. I also sourced two used Square D 3 phase 100 amp. disconnects removed from industrial applications and wired them for single phase 240 volts. These were only $75 each from eBay but retail for $450 each from an electrician or supply house. This allowed me to use 1 AWG copper run in 1 1/4" plastic conduit from each 200 amp. main panel to the disconnect enabling little to no voltage drop in each of the 40 and 45 foot runs respectively. I used 2 AWG copper from the disconnect to the HPWC's and both are set for their full 100 amp. capability. The house has a 400 amp. service so each HPWC is on a separate 200 amp. panel.
    I was going to install the working bay (the ones with the lift) HPWC on the wall next to the air compressor until my wife, who is not an engineer like me, suggested I mount it on the lift post in the center of the two bays so it could be used from either parking spot. Once again the old adage: "She may not always be right but she is never wrong" applies big time. What should have been so obvious to me but wasn't is beyond me and I fully admit she got it so right on this one. Just one more reason I love her so.
    The installation on the lift post required the fabrication of some mounting brackets for the HPWC so there is no interference with the lifts mechanism. I couldn't help myself with the old gas pump sign just to remind me of the fossil fuel past I came from and am now leaving behind. So now I think we are pretty well set to charge both of the Tesla's to be and any friends and visitors as well.
    IMG_0258.jpg IMG_0252.jpg IMG_0255.jpg IMG_0261.jpg IMG_0259.jpg IMG_0253.jpg
     
  16. bonnie

    bonnie Oil is for sissies.

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    ... the EV geek in me wants you to know that the first reaction was 'pritty'.

    :)
     
  17. tga

    tga Active Member

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    I like your suggestion on ebay sourcing, mounting on the lift post for dual bay access, and your shop layout (is that a beer fridge I see in the corner? :smile:)

    How did you attach to the lift post? I'm leery to drill mine...
     
  18. Mnlevin

    Mnlevin Member

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    Total waste of money unless you run a car service and need to turn your cars around quickly. I have had my MS60 for about 1 1/2 years and NEVER had a time that I needed to come home and quickly charge the car to go out again. Even if I had a second MS or GenIII, you can plug one car in and before you go to bed move it over to the other, or like someone said have 1 line with a timer. Even the HPWC is a waste unless you see yourself running 200 miles then coming home and needing to go another 200 miles
     
  19. bonnie

    bonnie Oil is for sissies.

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    It's a total waste of money until you have a friend with a Roadster or Model S visiting for the afternoon, needing to top off before heading home, and you want to supply a high power charge. Or you have a bbq with 100+ people, with about half driving EVs, some Leafs with a very short range ... and many need juice just to get home again.

    I used my 14-50 for years and it fully served my needs. But after taking friends to different area EVSEs so they could charge while visiting, I went the extra and put in more options. Totally glad I did. And I'll probably put in more options in the next year. Because I'm not the only one who charges at my house. My friends do, too. And I like them to come visit. :)
     
  20. Solarguy

    Solarguy Member

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    Yes it is a beer fridge, soda too :smile:

    I to was leery about drilling the lift post not because of structural integrity but for interference issues. On mine there is 1/2" of free space 2 1/2" in from each side that the lift carriage does not obstruct. This space allowed for the four 1/4" holes and hardware for the disconnect to be mounted as well as two holes for the brackets I fabricated. All lifts are different so study yours closely to see if there is any area that would not get in the way of the carriage as it travels. So I guess the real answer is "very carefully".
     

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