TMC is an independent, primarily volunteer organization that relies on ad revenue to cover its operating costs. Please consider whitelisting TMC on your ad blocker or making a Paypal contribution here: paypal.me/SupportTMC

My Fuse Box Configuration : Is 14-50 Nema connection possible with current setup ?

Discussion in 'Model S: Battery & Charging' started by AprilDelivery??, Mar 20, 2013.

  1. AprilDelivery??

    Joined:
    Feb 2, 2013
    Messages:
    145
    Location:
    NY
    I have a fuse box with the following configuration , see photo below. Is it possible to hook a 14-50 Nema connection by changing the A/C 220 v (see second photo) three prong outlet to 4 prong 14-50 ? Plus additional question, I have two 100 amp switches on the main switch, see photo 1 , can I add HPWC cable to this fuse box?





    fuse1.jpg wall1.jpg
     
  2. mknox

    mknox Well-Known Member

    Joined:
    Aug 7, 2012
    Messages:
    8,568
    Location:
    Toronto, ON
    You have a 100 amp main service, and I don't see anything that looks like an electric range, electric water heater or electric clothes dryer so you *may* be able to support a 50 amp (40 amp continuous) circuit there. Best to check with a licensed electrician. (You have a 2-pole ganged 100 amp breaker)

    That outlet is a NEMA 6-20 (20 amp, 240 volt) outlet that is likely fed with conductors too small to support a NEMA 14-50. There likely is not even a neutral conductor behind that outlet (probably just two live legs and ground).
     
  3. AprilDelivery??

    Joined:
    Feb 2, 2013
    Messages:
    145
    Location:
    NY
    I have a electric clothes dryer(see photo), electric water heater but that 6-20 Nema 240 outlet is connected to a 20,000 btu Air Conditioner.
     
  4. yobigd20

    yobigd20 Well-Known Member

    Joined:
    Oct 28, 2012
    Messages:
    5,793
    Location:
    Skaneateles, NY
    Well, your main is 100amp, yet you have 335amps in breakers. But what matters is the total continuous load at any given time from all the circuits combined. If you turn on every device in the house, would you exceed 100amp and trip the panel? Probably not. But if you add a NEMA 14-50 for charging a model S, and that alone is pulling 40 amps continuous, then yes I would say it's very likely your main breaker is going to run too hot and trip frequently. So while you may have plenty enough room in your breaker box for all kinds of new circuits, there's just not enough power from the main to satisfy the total load when you add the Model S. and completely forget about the HPWC until you get a main upgrade.
     
  5. Lloyd

    Lloyd Active Member

    Joined:
    Jan 12, 2011
    Messages:
    4,885
    Location:
    San Luis Obispo, CA
    Next step is to see what the panel is rated for. If it is a 200 amp panel, and the pull is not too far to your meter, it might be an easy fix to upgrade to 200 amps. Then you would have ample power for all your AC, water, dryer, car and other appliances.

    Take a picture of the Murray sheet on the door to your panel.
     
  6. FlasherZ

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

    Joined:
    Jun 21, 2012
    Messages:
    7,019
    You're going to need an electrician to tell you anything more, really. Even if the panel is a 200A rated panel, the entrance conductors might be only 2/0 or 1/0 AL. Either way, you'll need a permit, inspection, and meter pull (unless you have an outside disconnect) and it'll have to be done to code.

    From what I can see, in your existing panel you'd likely be able to install a NEMA 14-50, or you'd be able to set up the HPWC with a 40A charging current only (as mknox said). Looking at the loads listed, I see a couple of breakers that have A/C noted on them (probably for small window units) plus the 240V A/C outlet you note, refrigerator, etc.

    An electrician can look at what you have and tell you how easily (or not) you could upgrade things.

    - - - Updated - - -

    Should probably merge this with the other thread by the OP:
    http://www.teslamotorsclub.com/showthread.php/14709-What-Do-I-Need-To-Tell-The-Electrician-For-My-Electric-Meter
     
  7. AprilDelivery??

    Joined:
    Feb 2, 2013
    Messages:
    145
    Location:
    NY
    Below is a photo of the Murray sheet for my panel. Its rated 125 amp but I have two 100 amp breakers on top and my outside meter says 200 amp (see photo 2). So maybe I can add a 50 amp then a 14-50 nema connection. But I don't think a 100 amp HPWC connection? Do I have to upgrade the amp?
     

    Attached Files:

  8. mknox

    mknox Well-Known Member

    Joined:
    Aug 7, 2012
    Messages:
    8,568
    Location:
    Toronto, ON
    Don't worry about the meter outside. That is the utility's property and is not (really) relevant to the size of your electrical service. This type of self-contained meter is good for services up to 200 amps and if you upgrade or install a service larger than that, your utility will upgrade the meter to one of the appropriate class. The service conductors between the meter and your panel may only be sized for 100 amps.

    You have a 100 amp service. The breaker is a 2-pole ganged breaker that looks like two, but it is really just one. 120/240 volt systems consist of two "live" conductors and a neutral. Each of the two "live" legs need to be fused while the neutral is connected straight through and bonded with a ground (like a water pipe) in your service panel. Each live leg to neutral gives you 120 volts while live leg to live leg gives you 240 volts. 120 volt circuits in your home are fused via a single pole breaker while 240 volt circuits (stoves, dryers etc.) are fused via a two pole ganged breaker.

    An electrician familiar with the codes and regulations in your area will tell you for sure, but you may have capacity for a 50 amp circuit feeding a NEMA 14-50. You will not be able to supply a 100 amp circuit to a HPWC with your existing service entrance equipment.
     
  9. drees

    drees Active Member

    Joined:
    Jun 23, 2009
    Messages:
    1,121
    Location:
    San Diego
    I don't see any circuits there that look like you have electric clothers dryer or electric water heater - both of those would definitely run on 240V - the dryer would be on a 30A circuit and the water heater would be on a 50A circuit. All your circuits are 120V except for the one marked A/C living room.

    The panel itself is rated for 125A from the picture - like the others I suspect you may be able to get a 50A circuit installed for EV charging, but you'd have to run a load-calculation to make sure. At a minimum you may be able to get away with upgrading the wires that feed the panel to handle 125A, but depending on cost you may want to just upgrade the whole thing to be able to handle 200A.
     
  10. ahaer

    ahaer Member

    Joined:
    Nov 16, 2012
    Messages:
    25
    Location:
    Norwood, MA
    To clarify - he has a 100amp 240V main and 335amp in 110V loads. So he can draw up to 200amps at 120V (assuming the load is equally distributed over each leg) before tripping the main...

    I don't know the rules but my 100Amp panel runs an electric range, electric stove top, central air and a volt charger (only 12amps at 240V) without tripping the main. However, it needs to be replaced for other reasons and I will be upgrading to 200amp service when I do.

    If you want to avoid the panel upgrade you can always charge at a lower amperage, after all you have all night to charge...
     
  11. AprilDelivery??

    Joined:
    Feb 2, 2013
    Messages:
    145
    Location:
    NY
    On the A/C 6-50 Nema 240 V 20 Amp outlet , whats the most I can charge ? 4-5 miles per hour or more?
     
  12. Lloyd

    Lloyd Active Member

    Joined:
    Jan 12, 2011
    Messages:
    4,885
    Location:
    San Luis Obispo, CA
    240 V 20 amps will get you 10 to 12 MPH
     
  13. AprilDelivery??

    Joined:
    Feb 2, 2013
    Messages:
    145
    Location:
    NY
    Are you sure? I heard it might default to 10 amp and only get 5 miles per hour. Thats good if it get 10-12 mph its twice as fast !
     
  14. FlasherZ

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

    Joined:
    Jun 21, 2012
    Messages:
    7,019
    You will be charging at 16A, at about 12 rated miles per hour of charge.

    That said, Tesla doesn't make an adapter for that outlet. For reasons noted in the charging FAQ, you shouldn't try and adapt this outlet.

    You should bring in an electrician who can determine whether you can support a 24A load (NEMA 14-30 receptacle), a 40A load (NEMA 14-50 receptacle), and the cost to upgrade to 100A capability for HPWC.
     
  15. AprilDelivery??

    Joined:
    Feb 2, 2013
    Messages:
    145
    Location:
    NY
    No, I saw that Tesla has that 6-50 Nema adapter in the the Tesla Store so I can use it and charge 12 mph. But does Tesla include it with Model S? Or do you to have to buy separately?
     
  16. mknox

    mknox Well-Known Member

    Joined:
    Aug 7, 2012
    Messages:
    8,568
    Location:
    Toronto, ON
    Mine came with a NEMA 5-15 (standard 15 amp, 120 volt outlet) and a NEMA 14-50 (electric oven, campground etc. 50 amp, 240 volt). I originally had heard that you could substitute, but I was given no such option when I picked up.

    Tesla adapters for purchase are here.
     
  17. bluetinc

    bluetinc Member

    Joined:
    May 11, 2009
    Messages:
    682
    Location:
    MD
    The confusion here is that you call out a Nema 6-50 outlet, which by definition is a 50 Amp, 240V outlet, that then allows you to charge at 80%, or 40Amps, which is 31 miles per hour charging "rated" ( (240V * 40A)/305 Wh/mi). You then follow that with a 20 Amp comment, hence the strange answers. The 6-50 plug Tesla sells is not the same as a 6-20. The outlet you showed is a 6-20 which you would legally (NEC) be able to charge at 80% of 20 Amps, ((240V * 16A)/305 Wh/mi ), or 12 miles per hour. In reality you will be just a bit below those numbers due to heating of the pack and or losses in the charging circuit.

    Peter

     
  18. FlasherZ

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

    Joined:
    Jun 21, 2012
    Messages:
    7,019
    Receptacle and plug standards have 2 numbers, as bluetinc noted. There's the NEMA series number, which specify the availability of certain types of power and the voltage, then there's the NEMA listed power rating. In your case, you have a NEMA 6-series receptacle (240V-only with ground), but only 20 amps available.

    Tesla does not sell an adapter for a NEMA 6-20 receptacle, which is what you have.

    I can probably guess the next question, so I'll answer it: You cannot safely replace that outlet with a NEMA 6-50 without new, larger wiring and circuit breaker. You should call an electrician.
     
  19. AprilDelivery??

    Joined:
    Feb 2, 2013
    Messages:
    145
    Location:
    NY
    I can get a NEMA 6-20 to 6-50 or 5-15 adapter then I would be able to charge at a higher rate ?
     
  20. FlasherZ

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

    Joined:
    Jun 21, 2012
    Messages:
    7,019
    A NEMA 6-20P to 6-50R adapter will violate NEC which will invalidate your homeowners' insurance, or make you liable (if renting) for any damage.
    A NEMA 6-20P to 5-15R adapter is not possible, as NEMA 6 is 240V and NEMA 5 is 120V.

    Please call an electrician. Have them tell you what it will cost to get you a proper NEMA 14-50 plug installed where you want to charge it. They can also advise you on HPWC upgrade costs.
     

Share This Page