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2nd panel versus subpanel?

Discussion in 'Model S: Battery & Charging' started by GasDoc, Nov 22, 2012.

  1. GasDoc

    GasDoc Member

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    Below is a picture of my smart meter and the main breaker for the house. The breaker panel that has all the switches for my home is located some distance from this.

    Directly on the opposite side of this wall is the ideal place for me to place a plug for charging my car.

    Should I ask the electrician to install a panel that connects to this location instead of running a subpanel from other breaker box which is about 30 feet away?

    It looks to me like there is the opportunity to wire in a second breaker directly above the one pictured and run that to a 240v panel --> NEMA plug dedicated to charging my car.

    Thanks in Advance

    main panel_3.jpg
     
  2. mknox

    mknox Well-Known Member

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    This looks like the main breaker/disconnect for the house. You can't add another breaker here in parallel and should have an electrician wire another breaker and outlet from your distribution panel (where the rest of the home's breakers are).
     
  3. GasDoc

    GasDoc Member

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    This is the main breaker panel.

    Too bad I can't split off another breaker from here. The location is perfect.

    I'll probably have to have the electrician run conduit from the unused 240v breaker that's supposed to be for the dryer.

    Just curious, how come I can't run another panel off from this location? Electrical code?
     
  4. mitch672

    mitch672 Active Member

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    #4 mitch672, Nov 22, 2012
    Last edited: Nov 22, 2012
    You can run circuits from there, but first you would have to replace all of that existing equipment (meter and disconnect), with what's called a "CSED"' which stands for "Combination Service Entrance Device". It's what they would do if for example, you wanted solar, but had no room in the main box for additional circuit breakers.

    I had one put in, it has a 200A main breaker, then has 8 positions for circuit breakers (4 - 2 pole breakers), the bottom of the buss bars have lugs, that's where the wiring enters the house to the main panel. With service entrance equipment like this, you can add a 50A 2-pole breaker for your 14-50, or you can add a subpanel off one of those 4 positions.

    SquareD PDF on CSEDs: http://static.schneider-electric.us/assets/pdf/retail/Combination-Service-Entrance-Devices.pdf

    Lowes has them for $155.00
    http://www.lowes.com/pd_79498-296-RC816F200C_4294722561__?productId=1196613&Ntt=squares&Ns=p_product_price|1

    Mine is made by SquareD, I believe its a model # "RC816F200C" here is a picture of it installed:

    ev14.jpg

    FYI: The PVC pipe leaving the bottom of the CSED runs to a new 125A subpanel in the garage, for EV charging.
     
  5. FlasherZ

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

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    Actually, depending upon the rating of the equipment you can indeed use a second disconnect here, as long as you don't exceed the rule-of-six (6 breakers max without a main breaker in the panel). However, new code requires that "off" be in the "down" position for any vertically oriented breakers now, so adding a breaker to this panel would be a code violation. You could replace this disconnect with a new panel that has multiple side-by-side breakers, or follow your original plan of routing it through the house's panel.

    - - - Updated - - -

    What is in the box below your meter? Can you open that and take a photo?
     
  6. mknox

    mknox Well-Known Member

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    It looked to me that the OP was suggesting placing another breaker electrically in parallel with what I assume is the main service disconnect. Typically, service conductors run from the utility, through the meter and then to the main disconnect. From there, conductors go to a distribution panel with breakers for each of the 120v and 240v branch circuits.
     
  7. FlasherZ

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

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    #7 FlasherZ, Nov 22, 2012
    Last edited: Nov 22, 2012

    The breakers aren't wired "in parallel", which would suggest that one load was connected through two separate breakers; instead, one breaker continues to serve the panel in the home and another will feed the NEMA receptacle.

    In the US, it is not required by NEC to have one and only "main service disconnect" for a building. You may have up to 6 disconnects (see NEC 2011 230.71(A)) which must be grouped together in a single service-rated enclosure, and clearly labeled. The combined ratings of all disconnects must not exceed the maximum rating of the service conductors from the meter base.

    As I mentioned earlier, though, doing so would no longer be considered code-compliant because the breaker on top would have the "on" position facing downward.
     
  8. GasDoc

    GasDoc Member

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    So nobody makes breakers that have the switch reversed so that with the bus connection on the bottom,"off" is in the "down" position?

    I'll try to access what's below the smart meter. The whole setup is inside of an access panel on the side of my garage, behind some shrubs. So, it's not easily accessible.
     
  9. FlasherZ

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

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    I am not aware of any.
     
  10. GasDoc

    GasDoc Member

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    Thanks for all the help. This has been very enlightening.

    I'm sure this has been answered elsewhere, but can someone tell me the minimum size breaker and conductor gauge to install in if my only purpose is to charge my car (single charger, no high power wall connector). The run from the breaker to the NEMA plug will be less than 10 feet.
     
  11. hcsharp

    hcsharp Active Member

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    #6 AWG copper 6/3 + G, 50A breaker 240v. 30 ft is not very far if you have to run from your existing breaker panel.
     
  12. FlasherZ

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

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    O/T, but I can't believe I missed this the first time, you have a serious code issue with your wires there. Your white conductor shouldn't be used for hot, and the red conductor shouldn't be used for neutral, even with tape.

    6/3g is correct for a NEMA 14-50R, which is what's recommended because of the pervasiveness of campground service using that receptacle. 6/2g can be used for a NEMA 6-50R if you want to save one conductor; it's used for welders but is much less prevalent in the wild.
     
  13. GasDoc

    GasDoc Member

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    Obviously I'm going to let an electrician fix this, but is it a simple matter of swapping them both on this end and where they terminate (that would be my circuit breaker box, right?) and taking the tape off?
     
  14. mitch672

    mitch672 Active Member

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    Yes. However it shows very sloppy work that the original electrician who did the work was that lazy. The wires might be too short on the breaker box end to swap, that may be why its like it is...

    Just have the electrician replace the meter and disconnect with the CSED link I posted above, the CSED contains the meter mount, a 200A breaker, and buss bars for 4 additional 2 pole SquareD Homeline breakers, your 14-50 can be connected to a 50A breaker in 1 of those 4 positions available. You will also have 3 additional positions if you need to run a subpanel somewhere else, or if you ever get solar, the inverter can be connected their. At the bottom of the buss bars, are "main lugs", you connect these to the wires feeding your house... The CSED is the simplest, lowest cost way to get this all done. You're wire run to the 14-50 will be much shorter, if you said it was on the other side of this equipment, no need to run it to the main panel with the CSED.
     
  15. GasDoc

    GasDoc Member

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    The problem is that the meter is mounted INSIDE of the wall of my garage within an access panel. Within my garage there is actually a column that juts out which houses this stuff.

    So changing out the meter and installing the CSED is no easy feat.

    The thing that would make the most sense would be to reverse the whole configuration and install the meter and CSED inside of my garage, essentially turning the whole setup 180 degrees. But this would place the meter inside of my garage. Not sure if that matters, since it is a smart meter; it's not like anyone is coming by and reading it through the little window in the access panel as it is now.

    So can a smart meter and main breaker reside within a garage with no access from the outside?
     
  16. FlasherZ

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

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    #16 FlasherZ, Nov 23, 2012
    Last edited: Nov 23, 2012
    Yes, the service equipment ("CSED") you have linked is one way to do it, but isn't the ONLY way. Some PoCo's require specific meter bases -- for example, mine won't allow you to use the equipment you linked. In my case, the PoCo supplies the meter base and the disconnect is of my choosing.

    This work will require you to pull a permit and schedule an inspection, and the electrician can do this for you.

    - - - Updated - - -

    No. Even with smart meters, the meter must be readable without any special access (state utility regulations). In addition, when I lived in Palo Alto and San Jose, electrical code required an accessible/unlocked, external disconnect -- and I believe that's true of most of California.

    My guess on your swapped conductors, without looking, is that Mitch is correct - one of the conductors was cut too short and therefore the person who did the work swapped the conductors so he didn't have to run a new wire.

    I would call an electrician. He will have several options for you. One may be to take the feed from your existing disconnect, use that to feed a panel inside your garage, which in turn would feed the house panel and provide a branch circuit for your car charging (i.e., put a box in the middle). Another may be to simply do a run from your home panel. A third would be to replace the external disconnect with something that can hold more than one breaker. A fourth may be to replace your service equipment with a bigger disconnect, like what mitch suggests with the "CSED". Heck, there may be a fifth option, in that local code may allow you to have a breaker upside down -- it really depends upon code that's been adopted in your municipality.

    - - - Updated - - -

    Finally, a word of caution about these lugs: with rare exception, feeders require line-side OCPD's (NEC 225). You will not be able to connect your existing home wires to main lugs at the base of a 200A breaker, because the wiring from your disconnect appears to be a #2 or a #1/0 aluminum wire, good for only about 100A or so. Even with a main breaker in your house's panel sized appropriately for that wire, you can run afoul of code. You will likely need a breaker in your disconnect that matches the maximum rating of your wiring feeding your home's panel -- of course, check with a local electrician who knows code in your area.

    What value is that breaker in that disconnect? (I tried to zoom in but couldn't read.)
     
  17. mknox

    mknox Well-Known Member

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    I meant in parallel with the incoming utility supply. (1 feed from the meter supplying 2 breakers and branch circuits). I work for an electric utility in Canada, and we would never, ever allow that on a residential service. We require 1 main disconnect, and then you can do whatever you want (within code, of course) downstream of that main disconnect. Even sub panels (garage, out buildings etc.) are fed from a breaker and circuit downstream of the service's main breaker. Some small/medium commercial services bring the utility feed into a splitter bus from which individual meters and accounts are connected, but there is still a single main disconnect for each sub-service downstream of its meter. The Canadian and US codes are very similar, but there are nuances. One thing that may be different here is that the service connections must meet both electrical code and local utility conditions and requirements. Services (new and upgrades) are inspected by an independent safety agency (Electrical Safety Authority in Ontario) and the local utility before being energized.

    The OP should probably check with their local utility and/or a qualified electrician familiar with the service area first.
     
  18. mitch672

    mitch672 Active Member

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    The CSEDs are made with 100A and 200A main breakers. If he only has a 100A or 150A main service, he could take this opportunity to upgrade the entire service, or up to 125A breakers are availble to fit the 4 positions available inside the CSED which could be used to feed the interior panel (in which case you wouldn't use the CSEDs "main lugs"), so those conductors feeding the interior panel would be protected with the correctly sized breaker. Whatever is done is going to cost some money, and an electrician needs to be involved, and permits taken out.
     
  19. GasDoc

    GasDoc Member

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    Yup. Time to get the electrician back out to take a second look.
     
  20. FlasherZ

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

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    Not a big deal in the US. You frequently find multiple service panels pulled from the same service - as long as you follow the 6 disconnect rule you're ok. My own home is an example.

    I agree you need a local electrician to give you options especially in the People's Republic of California.
     

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