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NEMA 14-50 question

Discussion in 'Model 3: Battery & Charging' started by octoad, Jun 11, 2018.

  1. octoad

    octoad Member

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    i has an electrician install a NEMA 14-50 just before taking delivery of my Tesla. Once I had the car, I discovered my UMC plug doesn’t fully sink into the NEMA 14-50 outlet. There is about a 4mm gap where I can see the other plug prongs. Isn’t this a big no-no? Does anybody else have this issue?
     
  2. GregRF

    GregRF Squirrel Power

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    Press harder?
     
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  3. eprosenx

    eprosenx Member

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    Yeah, I would second that. Or is it not going in because there is an interference issue of your outlet or something (like the cord is getting caught on some waterproof box cove or something)?

    That seems wrong?

    Though also, it is possible that last few mm does not have any functional difference as long as you are past the compression connectors.

    Can you post pictures?

    Also, what model of receptacle do you have? (what brand - pictures would be good again)
     
  4. davewill

    davewill Member

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    Assuming that pushing harder isn't the cure, I'd push the problem back on the electrician. He may have used a cheap outlet that isn't quite to spec or it may be defective or installed wrong. There should not be a gap.
     
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  5. octoad

    octoad Member

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    Hah. Pressing harder did the trick. I had to really give it some force to get it to recede all the way in.
     
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  6. Quickstart88

    Quickstart88 Member

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    Hello Octoad -

    Delivery date is coming. I am currently installing the Nema 14-50 receptacle with 40 amps breaker. The UMC should just connect. Right? Looks like you are in SoCal perhaps you are with So Cal Edison. I am searching to see if there's any rebate or discount on charging.
    I think there's some rebate for that. The question here is if you get the tesla wall connector, you can't just plug the wall charger to the Nema 14-50 receptacle. Anyone have any suggestion? Perhaps go with some other wall charger and just be able to plug it into the Nema 14-50 receptacle.
     
  7. TexasEV

    TexasEV Well-Known Member

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    The NEMA 14-50 outlet should be installed with a 50A breaker, not 40A. Here is Tesla’s installation guide:
    https://www.tesla.com/sites/default/files/pdfs/installation-guides/NEMA_14-50_installation_guide_NA_US_2017.pdf
     
  8. brkaus

    brkaus Active Member

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    The wall connector is not UL listed for adding a pigtail to plug into a 14-50. Sure, it can be done and some do. Be absolutely sure to use the correct wire gauge pigtail and keep it as short as possible. Insurance isn't always happy if things aren't all done to code and UL listed as applicable.

    If your putting in a 14-50, why not just use the included portable connector?
     
  9. P85_DA

    P85_DA Supporting Member

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    SCE gives u this rebate Clean Fuel Rewards Program | SCE Clean Fuel Rewards Program

    You also can switch to TOU plan
     
  10. eprosenx

    eprosenx Member

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    While it is code compliant to install a NEMA 14-50 on a 40 amp breaker (if you are only planning on using a 32 amp UMC Gen 2), I would generally not recommend this unless you already have the wire in place that you are trying to re-use. I generally recommend installing wire capable of 50 amps and a 50 amp breaker.

    If you get a Wall Connector, I would recommend just hard wiring it in per the instructions. I don't understand the desire to plug them in?

    It is within code to install a NEMA 14-50 receptacle intended to be used with a UMC Gen 2 (32 amps continuous) on a 40 amp rated wire and breaker. Though I generally would not recommend going that route (I would future proof with a full 50 amps).

    Though now that I think of it more, NEC also says you must follow manufacturers installation requirements and so the question is: Does the doc linked to above apply and mean you have to install 6 AWG and a 50 amp breaker? I think the answer is no since the UMC is not a device that falls under NEC since it is not hard wired in. It falls under UL rules. If we were talking about a Wall Connector that might be different.

    I don't understand the desire to put Wall Connectors on pigtails here on the forums. To the point @brkaus made, yes, the Wall Connector is NOT LISTED for adding a pigtail. NEC says you need to follow manufacturers instructions and this is deviating from this. It also says pigtails are not allowed on permanently installed devices. Furthermore, even for devices they are allowed on, they can't be more than 12 inches long.

    On the comment about using the UMC Gen 2: The downside of that is that it only goes to 32 amps where the Wall Connector can do more.

    And finally, if installed with a pigtail into a 14-50 then the max output of the Wall Connector must be 40 amps or less. In my case, I ran #6 wire in conduit and so by hard wiring that into my Wall Connector I was able to put it on a 60 amp circuit and charge at up to 48 amps which is the max my Model 3 can take.
     
  11. Quickstart88

    Quickstart88 Member

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    Oh Crap - Okay let me rephrase my question. I've installed a Nema 14-50 receptor. Ran my 6 AWG gauge wire to a 40 amps breaker. I am planning to use my mobile connector with the adapter to the 14-50 receptor. This should work. Right? I should be able to pull in 32 amp charge rate. Is that right or do I have to upgrade my breaker to 50 amps?

    Yes I am planning to use my mobile connector for now. Not going to install a wall charger yet.
     
  12. eprosenx

    eprosenx Member

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    Yes, this is totally fine. You can charge at the full 32 amp rate of a UMC Gen 2 (I am assuming you are getting a UMC Gen 2 - if a UMC Gen 1 this would not be code compliant or safe since it can pull a full 40 amps).

    Can you tell us exactly what kind of wire you ran? Was it NM (Romex) or is it 100% in conduit (raceway)? I ask because I want to know if you can later just simply swap to a 50 amp breaker, or if you are limited to a 40 amp breaker since you used NM wire?

    If you have the right kind of wire on a NEMA 14-50 receptacle I would just go ahead and swap the breaker now to 50a even though you don't need it with a UMC Gen 2. A 50a breaker is ten bucks at Home Depot for most modern panels. ;-)
     
  13. Quickstart88

    Quickstart88 Member

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    New to all this. I am getting my Model 3. I think it's a Gen 2 Mobile UMC that comes with the model 3. Right? As for the wires, I went to Home depot and found some 6 gauge cable. Not sure what type. I also pick up a 40 amps Zinsco double pole breaker. These are 60 bucks breakers for the 40 amps. I wish they are like ten bucks.
     
  14. eprosenx

    eprosenx Member

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    All new Tesla's ship with the Gen 2 UMC now so no worries there.

    Can you post a picture of the wiring and the writing on the side of the wiring? Or the package/box?

    Regardless, it will certainly be rated to 40 amps so you are fine.

    I see on the breaker. That is an odd / old one I am guessing. Highway robbery eh! ;-) Thats why you always want to buy stuff for your home that has been installed in tens of thousands of tract homes. There will always be parts available and probably for cheap. ;-)
     
  15. Quickstart88

    Quickstart88 Member

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    I bought all these stuff with my electrician. Luckily we are planning to do the install tomorrow. Depending if he is free tomorrow.
    I don't have the stuff with me. I thought somewhere I read 8 gauge wires was good enough but I decided to pick up the 6 Gauge wire.
    Here's the breaker I bought.

    Connecticut Electric New VPKUBIZ Thin 40 Amp 3/4 in. 2-Pole Zinsco RC3840 Replacement Circuit Breaker-VPKUBIZ0240 - The Home Depot

    I don't have the wire with me.
     
  16. eprosenx

    eprosenx Member

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    Ok, you will be fine and have a code compliant install (at least in the US under NEC 2017). If you post more info on the wire we might be able to tell you if you can later up it to a 50 amp breaker.

    I personally would label the outlet with a label that said "Fed from a 40 amp breaker". That might be a clue to someone in the future that it is only on a 40a breaker and not a 50a breaker.
     
  17. Quickstart88

    Quickstart88 Member

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    You've been most helpful eprosenx. I figured a 40 amps breaker with 6 gauge wire is plenty. Won't be able to send you the wire on the cable. Perhaps tomorrow. I did took a quick picture earlier. I try to zoom in but didn't see any writing on the wires.
     

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  18. eprosenx

    eprosenx Member

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    Ok, I just realized I had a major brain fart on several of my previous posts. I was in another thread talking about using #8awg on a 14-50 receptacle as well.

    To correct myself: On any type of #6 AWG wire you are fine using a 50 amp breaker. Romex (NM) or not, you can just switch the breaker to 50a and be fine on #6 AWG.

    What this actually means is that since the parts you just linked to show conduit parts and presumably THHN wire, you can actually use the 75c rating of that wire to do up to 65 amps. So you could use that to wire up a Wall Connector to a 60a breaker and charge a model 3 at the full 48 amps rate.

    I personally would go return that 40a breaker and get a 50a one, but that is just me. I suspect the cost is not much (if any) different? But your install is code compliant even with just a 40a breaker.
     
  19. P85_DA

    P85_DA Supporting Member

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    Wow @Quickstart88 you have a zinsco main panel ? There are a lot of documented issues with those and FPE panels :(
     
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  20. Quickstart88

    Quickstart88 Member

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    Ha ha I was just chatting with my electrician. He said I am over reacting. #6 wire is fine with 50 amp breaker. He also ask if I really want to switch out the 40 to 50 amps in doing so - that's is taking 1/2 of my total home amps. My breaker panel is only 100 amps. Do I really want that?

    If I upgrade to 50 amps, using my mobile 2nd gen UMC, it can do a top 32A charge rate. Correct?
    The real benefit if having the 50 amps is if I decide to add the power wall charger. What charge rate will I be getting using a pw wall charger with a 50 amps. Trying to find out the benefit of buying a power wall charger.
     

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