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Charging with 30 Amps

Discussion in 'Charging Standards and Infrastructure' started by Kevin Harney, Jun 22, 2015.

  1. Kevin Harney

    Kevin Harney Active Member

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    I have on old 30 amp hot water heater circuit in my house that is unused. How much charging could I get out of that? What is the best choice ? HPWC? :confused:
     
  2. Cosmacelf

    Cosmacelf Active Member

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    If it is a 240V circuit, then you would be able to draw 24A from it, giving you about 18 miles per hour of charge.

    Presumably that hot water heater was direct wired, so it doesn't have a receptacle, correct? Are you looking to reuse the wires that went to the hot water heater, and install a receptacle?
     
  3. Rocky_H

    Rocky_H Member

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    I don't think a HPWC is supposed to be set up on a circuit that low. I thought it needs to be at least 50A. If your circuit is 240V 30A, I would think putting a NEMA 14-30 or 10-30 (depending on what wiring it has) dryer outlet on it would be a good plan, as Cosmacelf was alluding to. You can get an adapter to that from EVSEAdapters.
     
  4. Father Bill

    Father Bill Member

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    The HPWC can charge all the way down to a 15 amp circuit. But if your car does not have dual chargers and you never plan to upgrade your breaker/service I would go with something from Clipper Creek. They are very reliable and downright cheap ($ wise not quality). I have owned 2 and only upgraded to the HPWC to get 80 amp charging.
     
  5. davewill

    davewill Member

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    #5 davewill, Jun 22, 2015
    Last edited: Jun 22, 2015
    The HPWC will certainly go down that low. He won't be able to install a 14-30 outlet because he probably doesn't have a neutral AND ground, and you're not allowed to install new 10-30 outlets. He'd have to do a 6-30. Tesla only sells a 10-30 adapter, so he would then have to make a 6-30 to 10-30 adapter, or use a 6-30 to 14-50 adapter and rely on dialing the car's amps down, something I'd never recommend as a daily charge situation.

    Personally, I'd do the HPWC and look forward to the day I was ready upgrade the circuit.
     
  6. Rocky_H

    Rocky_H Member

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    Oh, right. I forgot about the outlet being considered a new installation, so you aren't allowed to do a 10-30. As you suggested a 6-30 or L6-30 would probably work with that wiring. Clipper Creek does have units that plug into L6-30. That would probably be the most convenient solution.

    The thing that frustrates me a little about the Clipper Creek units is how much they derate from the circuit level, so you're not getting as much charging speed as you should be able to get. For ones that are running on a 30A circuit, they won't supply any more than 20A, even though they should be able to do 24A. For the ones that run on a 50A circuit, they won't supply more than 30A, even though they should be able to do 40A. They seem to be going for the non-Tesla vehicles, where their maximum onboard chargers are only about 6.6kw.
     
  7. Father Bill

    Father Bill Member

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    Actually the HCS-40 will charge at 32amps on a 50 amp for about 7.2kw and they have another one that will do just over 11kw. But again if he is on a 30 amp circuit no need to get a higher rated EVSE. YMMV
     
  8. Lloyd

    Lloyd Active Member

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    That's because they have found that everyone's wiring is not perfect. They de-rated the units to accommodate the variations in installations. Safer for them rather than running at the maximum allowed.
     
  9. Cosmacelf

    Cosmacelf Active Member

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    The easiest thing to do is to put in a NEMA 14-30 receptacle and then use the Tesla supplied UMC to plug into it.
     
  10. BFCobra

    BFCobra Member

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    I ran a 50 amp rated wire to a 30 amp dryer plug and use the portable charger to get 20 to 23 miles per hour of charge for Tesse. Works fine, long trips I hit the SuperChargers, LA or Bay Area for example.....
    I believe Common and Ground go to the same place in the electric panel.

    On the Dryer plug I used a: http://www.amazon.com/gp/product/B000MIAMDK?psc=1&redirect=true&ref_=oh_aui_detailpage_o02_s00
    Cord used: http://www.amazon.com/gp/product/B00LIAWB8K?psc=1&redirect=true&ref_=oh_aui_detailpage_o03_s00 fits nice and tight in 3/4" PVC in the hole I poked into the laundry room next to the garage.
    On Tesse's side: http://www.amazon.com/gp/product/B00192QB9M?psc=1&redirect=true&ref_=oh_aui_detailpage_o09_s02

    If the plug is too far away, like when the Prius gets into the garage for maintenance, then one of these gets me to the driveway: http://www.amazon.com/gp/product/B0024ECIP0?psc=1&redirect=true&ref_=oh_aui_detailpage_o04_s01

    I made a group of different plugs for getting power from various outlets should the need arise. I have it in the rear foot well, in a baseball bag, just in case....

    Tesse has been in my possession since late March, so I am new to this. Saturday coming back from the East Bay was the lowest Tesse has gotten at 27 miles left at plug in at the house using all the above. The 2007 Prius was in the garage for an auxiliary battery change. What batteries can die????
     
  11. FlasherZ

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

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    Except there are two problems: water heater circuits are usually provided with 10/2, not 10/3, so no neutral... in addition, Tesla no longer makes the 14-30. Tough position. I'd recommend running a new cable and reusing the breaker space.
     
  12. InternetDude

    InternetDude Member

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    I DIY my HPWC install, it is wired to a 30A breaker. Works great, go for it. It's 2 wires plus a ground.
     
  13. FlasherZ

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

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    Neither is possible on a typical water heater circuit. Only a 6-series will work. Both 14-30 and 10-30 require a neutral (and you cannot use the EGC). 14-30 requires 2 hots + 1 neutral + 1 ground (EGC). 10-30 requires 2 hots + 1 neutral (no ground). 6-30 requires 2 hots + 1 ground (no neutral).
     
  14. TurboFroggy

    TurboFroggy Member

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    A 10-30 is two hots and a ground, and would absolutely work in this situation.
    Disconnect the water heater and wire up a 10-30 outlet then get the UMC 10-30 adapter here:
    http://shop.teslamotors.com/collections/model-s-charging-adapters/products/nema-10-30

    Total cost for the outlet would be maybe $20-$30 in parts and $45 for the UMC 10-30 adapter.
     
  15. FlasherZ

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

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    No, it is not. A NEMA 10-30 is two hots and a neutral, and appliances are grounded through the neutral. Never hook a 10 series receptacle to 2 hots and a ground. The EGC (ground) in many cases is smaller than the size required for neutral, and it is illegal to connect a bare ground wire (as found in NM cable) to be used as a neutral.

    NEMA 6 series are grounding 250V-only. NEMA 10 series are non-grounding 125/250V. NEMA 14 series are grounding 125/250V.

    If you don't believe me, see the NEMA page on Wikipedia: NEMA connector - Wikipedia, the free encyclopedia

    In addition, it is illegal to install a new 10-30 receptacle where there wasn't one previously, since NEC 1996.'

    See my wiring FAQ (in my signature) for more information.
     
  16. mspohr

    mspohr Active Member

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    Youcould use the openEVSE and wire it directly (no socket). it only requires two hots and a ground, no neutral.it has built in ground fault detection and you can set it for an appropriate current.this would be a good solution until you upgrade your wiring.
     
  17. TurboFroggy

    TurboFroggy Member

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    Right from the Wikipedia page you linked from:

    "NEMA 10 devices are a curious throwback to an earlier time. They are classified as 125/250 V non-grounding (hot-hot-neutral), yet they are usually used in a manner that effectively grounds the appliance, though not in a manner consistent with most modern practice.As commonly used, 10–30 and 10–50 plugs have the frame of the appliance grounded through the neutral blade. This was a legal grounding method under the National Electrical Code for electric ranges and electric clothes dryers from the 1947 to the 1996 edition. Since North American dryers and ranges have certain parts (timers, lights, fans, etc.) that run on 120 V, this means that the wire used for grounding is also carrying current. Although this is contrary to modern grounding practice, such installations remain common in the United States and are relatively safe, because the larger conductors used are less likely to be broken than the smaller conductors used in ordinary appliance cords, and the current carried on the neutral conductor is small."

    The UMC uses only the two hots, it doesn't have anything needing 120V so the ground/neutral is only used for a ground. Even the 14-50 that comes with the UMC, the neutral isn't connected to anything inside the connector, you could saw it off and the UMC would work just fine. If the water heater was wired with 10/2 Romex, the ground/neutral would be the same size wire. Yes after 1996 a "new" receptacle would have to be a 15-30 with a neutral, but this is an existing circuit with no wiring changes on the panel end needed. If the original water heater circuit was put in prior to 1996, it would fall under the "existing installation" would it not?
     
  18. TexasEV

    TexasEV Active Member

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    I continue to be amazed at what people want to do to avoid installing a proper 50A circuit to charge their $80,000-$120,000 car.
     
  19. TurboFroggy

    TurboFroggy Member

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    Ha, so true.

    How about just hard wiring a Clipper Creek LCS-25?
    http://www.clippercreek.com/store/product/charging-station-lcs-25-level-2/

    No "magical" 10-30 plug so that satisfies the Flasher man and NEC and it is still good enough to get you charged every night. It would also put no more stress on your existing panel then the original water heater did.

    Or better yet, just higher a proper electrician to come out and run a proper 8 gauge 4 wire 50 amp circuit for a 14-50 like TexasEV so eloquently mentioned. More then likely the cost of an LCS-25 would be about what it would cost to just have a proper 14-50 installed.
     
  20. purplewalt

    purplewalt Active Member

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    Not to mention what liability they might incur to their residence with less than premium (Electrical code) sized wiring.
    Would really hate trying to explain the wiring situation to their insurance agent after an untoward event.
     

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