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

home charging

Discussion in 'Model S: Battery & Charging' started by Vichin, Aug 12, 2014.

  1. Vichin

    Vichin New Member

    Joined:
    Sep 21, 2013
    Messages:
    4
    Location:
    Memphis
    Hi

    I recently moved to memphis and got a place on rent. My garage is 30 feet away from the dryer socket.

    I am new to this forum and i know its been discussed before but I need some advice on creating an extension cord from a 10-30 outlet used by my dryer (3 prong) to the car - 30 feet away. I bought a 10-30 plug and receptacle and ordered the NEMA 10-30 plug from tesla. What kind of wire should i use 10/2 ( with 3 wires - black white and naked) or 10/3(black red white and naked). The 10-3 plug and receptacle have only 3 places to connect wires.

    i am so confused with the ground neutral discussion on the blogs. I dont want to burn the house down or electrocute anyone. I need a simple solution.

    I am no electrician.

    Please advice

    Vichin
     
  2. Cottonwood

    Cottonwood Roadster#433, Model S#S37

    Joined:
    Feb 27, 2009
    Messages:
    5,062
    Location:
    Colorado
    The problem that you have it that the third pin on a 10-30 is a neutral, and not a ground. You really want to use 3 insulated conductors (even if one uses green insulation). Bare wires are meant for ground connections and the 10-30 does not have a ground! Also, this cord will be flopping around the garage and needs to be pretty robust.

    My recommendation is buy a 10 gauge extension cord like this one "Yellow Jacket 2806 10/3 Heavy-Duty 15-Amp SJTW Contractor Extension Cord with Lighted End, 100-Feet - Amazon.com", get the 50 ft version, cut the ends off, and use it with your 10-30 connectors. Use the green insulated wire in the extension cord cable to connect the neutral pins in the 10-30 connectors. Then use the black and white wires consistently between the 10-30P and 10-30R; make sure that if you plugged the 10-30P into the 10-30R that all there wires are connected to each other in a circle.

    Good luck!
     
  3. Vichin

    Vichin New Member

    Joined:
    Sep 21, 2013
    Messages:
    4
    Location:
    Memphis
    Thanks, appreciate the advice

    - - - Updated - - -

    the wire states 15Amp 125volts. will it work with a 30 amp circuit?
     
  4. newdev

    newdev Member

    Joined:
    Mar 28, 2014
    Messages:
    47
    Location:
    Palm City/Stuart, Florida
    I am not an electrician either but No #10 wire is maybe large enough for 30amps.. but I would use #8. Two Live, One Neutral and make sure the box is grounded.
    Good Luck
     
  5. FlasherZ

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

    Joined:
    Jun 21, 2012
    Messages:
    7,019
    #10 SJTW is good for 30A rating, so 24A continuous load charging. As NEMA 10-30 connectors are 30-amp connectors, you're fine.

    (See 2011 NEC 400.5(A)(1), column B, for 2 current-carrying conductors)

    See my FAQ below. Note Tesla says "no extension cords" which means you violate code just by using one, although it's relatively low-risk.
     
  6. Canuck

    Canuck Active Member

    Joined:
    Nov 30, 2013
    Messages:
    3,949
    Location:
    South Surrey, BC
  7. Cottonwood

    Cottonwood Roadster#433, Model S#S37

    Joined:
    Feb 27, 2009
    Messages:
    5,062
    Location:
    Colorado
    That is #6 wire, certainly good for 40 Amp service on 14-50 connectors. For a general purpose cord with several adapters, using the cable you suggest, my electrician uses a NEMA L14-50 as the intermediate connector on the ends of the extension cord. I think this is probably a good choice for the intermediate connector on the 6/3 SOOW cable. Then make adapters to the outlet of interest.

    I have found that if I use #12 for 5-15/5-20 connectors, #10 for 14-30/10-30 connectors, and #6 for the 14-50/10-50 connectors with good connections on the installs and a reasonable utility connection the current does not fold back to the 75% level.

    It seems that the Tesla algorithm may have some absolute Voltage sensitivity, as well as relative (no current to max current delta Voltage) sensitivity. There seem to be more reports of the current fold back happening on 208 Volt connections, but the is all hearsay; I don't know of any hard test comparisons.
     

Share This Page