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Extension cord recs when there’s no info on outlet

Discussion in 'Prime Plug-in Charging' started by Inkyspace, Jan 16, 2018.

  1. Inkyspace

    Inkyspace New Member

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    So I’m totally new to this and find the topic a bit confusing so hopefully someone here can help me.

    I live in an apt bldg and have access to an outlet in my parking garage but the outlet is fairly high up on the wall. I definitely need to get an extension cord in order for my cord to reach. The problem is I have no idea what the voltage or amps or anything is of the outlet since I really can’t get close enough to the outlet to read it. I’ve asked my building manager but they have not been much help. They can only help me get a ladder and find a way to hang the cord once I purchase one. What would be the safest extension cord to buy for my Prius Prime Advanced when I know nothing about the outlet?

    Also does anyone have a link for somewhere that explains the whole voltage/amps/AWG/gauge stuff in simple easy to understand language for a newbie?
     
  2. JimboPalmer

    JimboPalmer Tsar of all the Rushers

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    1) Toyota warns you against using any extension cord.
    2) if it is a 110 volt outlet, it is almost assuredly 15 Amps. It is not assuredly a GFCI outlet as it should be to safely protect humans while you charge your Prius.
    amazon.com/Receptacle-Power-Outlet-Socket-Tester/dp/B01IR2OZ7Q
    3) the thicker (lower number gauge) the extension cord the better.
    amazon.com/dp/B01IN11IJ4/ref=twister_B01N5Q9SSB?_encoding=UTF8&psc=1

    Can you photograph the receptacle and post the picture here?

    15 amp 110 volt receptacle with polarity
    [​IMG]
     
    #2 JimboPalmer, Jan 17, 2018
    Last edited: Jan 17, 2018
    Elektroingenieur likes this.
  3. padroo

    padroo Senior Member

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    I would expect it to be a 20 AMP circuit and be GFI, garages are suppose to be GFI according to the National Electric Code. The maintenance guy should be able to tell you where the breaker is and it will have the amperage marked on it. For a short run inside the garage whether it is a 15 or 20 amp circuit I would use a number 12 gauge extension chord, it is rated for 20 AMPS. I don't know what your car requires.

    The trouble is there may be other loads on this I am assuming a branch circuit with other outlet so you may not be able to draw the total rated load from the circuit yourself. It's all in the details. It would be nice to have a dedicated circuit just for your car.
     
  4. wb9tyj

    wb9tyj 2017 Prius Prime Advanced

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    Not knowing if there is another load on that particular circuit, i wouldn't put a car load on it not knowing what else is there...as previous posts indicate...a #12 extension cord would be rated at 20 A would be required...The car itself would pull 12-16A when charging...the car can be set down to 8A draw but the time to charge increases...
    More than likely the plug is 120-140V AC rated for 20A...so putting your car on there, and somebody else has a 10A draw on it would overload it and pop the breaker somewhere...
     
  5. Elektroingenieur

    Elektroingenieur Senior Member

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    @JimboPalmer and @wb9tyj make excellent points.
    Some may say otherwise, but I’m afraid there isn’t one. Especially in an apartment building, where others might be at risk if something were to go wrong, you really should have an outlet (installed by an electrician, if necessary) that you can use for charging without an extension cord.

    As much as I’d like to offer a practical solution, I urge you to consider your liability exposure and the provisions of the electrical code that require the instructions for equipment to be followed (NEC 110.3(B)), prohibit using extension cords as a substitute for the fixed wiring of a structure (NEC 400.8(1)), and limit the total charging cable length, from outlet to car, to 25 feet (NEC 625.17(C)).

    Please don’t take this the wrong way, but if you don’t have the electrical knowledge to identify an outlet from a distance (most aren’t marked, by the way) and select a suitable cord, you also aren’t in a position to ensure that the installation is otherwise safe.
    Voltage - Energy Education
    Current - Energy Education
    Wire gauge - Energy Education

    If you’re looking for something more in-depth, the Navy Electricity and Electronics Training Series is often mentioned as a good self-study course.
     
  6. CraigM

    CraigM Active Member

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    A personal example:

    When I got my Fiat500e, I plugged the 120 Volt, 12 amp EVSE into my garage’s 20 amp circuit. No problem for the first 3 - 4 days, then my wife plugged in her 1875 watt / 125 Volt (15 amp) hairdryer! Popped the circuit breaker. For the next month we would coordinate between charging, and hair drying. We finally got a level-2 EVSE installed. You really need to know what else is on that circuit.
     
  7. vvillovv

    vvillovv Senior Member

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    Just sayin cause
    after bout 10 years of hearin "it popped again", I finally have to rewire the outside outlet and floodlight above + it's leadin, which mean removing siding.
    Long story short, I have 2 count um, 2 gfci outlets on the circut which feed the 1 outside outlet, basement washer/gas dryer and bathroom remodel job. I really should have split that circuit a LONG LONG time ago, when I repaired the outside outlet. I was "agassed" when I noticed the outlets feed a few weeks ago. I can't believe I didn't notice or didn't want to dig any deeper into it 20 years ago when I replaced the 3 outlets and floodlight switch,
     
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  8. Inkyspace

    Inkyspace New Member

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    Thanks for everyone's input. The maintenance guy told me the outlet is definitely 120V and either 20 or 30amps. I can take a picture of it and post it later today. The guy who had this parking spot before me had an extension cord to charge his car but he obviously took it with him when he moved out. So I know this outlet can support charging a car and an extension cord. With these specs can anyone recommend a safe extension cord? I would not need a long extension, definitely less than 25ft.
     
  9. walterm

    walterm Active Member

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    I've recharged successfully with a 25 foot 12/3 extension cord (bought from Amazon, for some reason posting the link results in just a blank space ).

     
  10. JimboPalmer

    JimboPalmer Tsar of all the Rushers

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    #10 JimboPalmer, Jan 26, 2018
    Last edited: Jan 26, 2018
  11. Inkyspace

    Inkyspace New Member

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    Does it matter that my outlet is 20-30amps (according to maintenance guy)? This item says it is rated for 15 amps?
     
  12. walterm

    walterm Active Member

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    The Prime EVSE will not draw more than 15 amps (I think it's spec-ed to draw 12, or 6 if you limit it from a car configuration menu). So you should be OK.
     
  13. I'mJp

    I'mJp Senior Member

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    Try home depot
    They have a 25 foot extra heavy duty, 10 gauge.
    Rated for circular saws and air compressors.
     
  14. Inkyspace

    Inkyspace New Member

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    So this one is thicker but still rated at 15amps. So would it be better to get a 10/3 vs. a 12/3 cord? And how do I know exactly how many amps my prius prime will draw?
     
  15. Inkyspace

    Inkyspace New Member

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    I would also prefer to be safer and get a cable that is overkill to be double sure that it is safe. So maybe I should go with a 10/3 cord? I also like that the one suggested by JimboPalmer comes in a shorter length of 10ft. I think I read somewhere in a different thread that the shortest distance is best? I'm also worried about how to hang it on the wall if the cord is too long... I read that it can overheat if you wrap or coil the cord?
     
  16. I'mJp

    I'mJp Senior Member

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    Just my opinion, I would have enough length so that it would reach from the front of the car or the back, or in the next adjacent parking spot (if there is one). Give yourself room to wiggle.
     
  17. Inkyspace

    Inkyspace New Member

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    I noticed that the previous 10/3 cable recommended was SJT and not SJTW. Does anyone have thoughts about this cable?

     
  18. fuzzy1

    fuzzy1 Senior Member

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    The shortest practical length is equally as important as using a heavy gauge. The voltage loss along the cord is a product of wire resistance (per foot) times length.

    With a proper heavy gauge cord, not tightly bundled or coiled, this should not be a problem. But a cord short enough to not need coiling (or more than two or three turns) is better still, and will reduce the cord's voltage loss.
     
  19. Gianni I

    Gianni I Member

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    I made my own extension cords to ensure I had top quality connections and specs. Cost me about $50 each (i made 2 of them). I've been using 1 every day to charge at home and have had no issues.
    Posted my cord and specs in this thread.
    Longer Charging Cable? | Page 2 | PriusChat
    Overkill is better safe than sorry here!
     
  20. JimboPalmer

    JimboPalmer Tsar of all the Rushers

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    For our purposes, you can think of 15 Amps as the shape of the plug.

    It is very likely your out let resembles the top one, rated 15 amps.

    [​IMG]

    Thick wire just means less heat in the cord and more power makes it to the end of the cord.