I can only park ~ 80 ft away from an outlet at work so I use a 100ft extension cord and I used to live in an apartment for a while. I have a second 100ft 12 AWG extension cord, but prefer not to use them in series (but will do that if needed), but I have used that second cord as a "fixed" outlet in my parking stall at that apartment. Our balcony was straight up from the parking slot and had outside outlets, so I secured the cord to our balcony and only plugged it in when I had the vehicle plugged in also. It worked fine to charge overnight that way and I could use my electric truck the whole time we lived there. At work I roll out my 100 ft 12 AWG cord. Luckily the outlet is 2 ft from the service panel. At 15 Amp, the drop is such that at the end of the cord I still get over 110V AC, so that is very acceptable. That was different in another building (and with a 14 AWG cord) where the plug was about furthest away from the service panel, very likely more than 100 ft of building wiring since the voltage at the outlet dropped to 105V at a 15A draw. Since that extension cord was also too thin, the voltage at the vehicle was only 90V which caused the current to be much higher than when receiving 120V, so the wires ran hot and the 15A protection on my power strip often tripped. parking in the back iso in front and using a short cord allowed me to get more than 115V and current dropped to around 12A. The issue with modern supplies and chargers is that they are constant-power, so they regulate their *output* and will try to pull from the inlet whatever needed to maintain the output power. If the voltage tanks, the current shoots up and some EVs have had a bad rap due to exactly this problem: For example Vectrix was bought by people who have no parking, they can't use a car, but can store a motorcycle somewhere nearby. They would try to feed their bike via an extension cord, but due to marketing push the charger was pushed to maximum power (just like the controller overtaxed the batteries to get good numbers for max speed) so the ~1500 Watts that the (crappy designed) charger would try to pull and which is just over 12A at 120V would skyrocket to over 15A when using a similar cord as that I was using for my previous EV. At that current, the charger would often fail (and due to its design, it was non-repairable unless you have a masochistic tendency) so plenty bikes sat unusable until a different type of charger was made available. Of course, the correct solutoin is that a charger monitors voltage and current. If either goes out of spec, it simply throttles back to protect itself, the extension cord and the house wiring and outlet. I don't know if the vehicles are that smart (note that it is not the EVSE who regulates voltage or current, it is a smart cord, while it is the vehicle that determines how its charger will respond.
My vehicle has an old-fashioned dumb charger that contains a (resonant) transformer, so the lower the input voltage, the lower the current. I find that when I plug in to a public charging station that is fed from 208V, the power my charger draws is similar to when plugging directly into a 120V socket, so I sometimes forego the "Level 2" chargers that supply 208V until I have added an extra switch to my transformer output that allows me to choose a higher tap (normally only used for higher pack voltages) to allow a decent current when connecting to 208V. Hope this clarifies, Cor van de Water Chief Scientist Proxim Wireless Corporation http://www.proxim.com Email: [email protected] Private: http://www.cvandewater.info Skype: cor_van_de_water Tel: +1 408 383 7626 -----Original Message----- From: EV [mailto:[email protected]] On Behalf Of Roland via EV Sent: Friday, December 12, 2014 7:15 AM To: brucedp5; Electric Vehicle Discussion List Subject: Re: [EVDL] EVLN: Should Extension Cords Be Used With Plugins?(don't get burned) Do not forget to calculated the length of the entire circuit from the circuit breaker panel to the charger. A standard 120 vac 60 hz 20 amp circuit using a No. 12 stranded copper should held to 20 foot circuit length for a 1 percent voltage drop. You can go up to 42 feet circuit length for a 3 percent voltage drop. This includes the breaker to receptacle circuit length plus the power cord to the charger. On a 20 amp circuit using a 20 amp receptacle, it is preferred to limited the current on a 20 ampere circuit to 80% or about 16 amps. On a 20 amp circuit using a 15 amp receptacle, it is preferred to limited the current to 12 amperes. The standard power cord for interior areas that is not being pull around on the floor constantly can be Type SJTO rate at 300 volts. For exterior areas, the cord should be a Type S or SO 300 or 600 volt rated, with water tight plug and connectors. Also rated for low temperatures. If the total power circuit is more than 42 feet at a 16 amp load from the circuit breaker panel, the first 42 feet should be a No. 10 AWG 19 stranded copper wire to a dedicated receptacle or make sure there is no other loads on that circuit. You can then use a 20 amp 300 volt rated stranded copper power cord up to 20 feet for a 2 percent voltage drop. It is best not to go over a 3 percent voltage drop. Roland ----- Original Message ----- From: brucedp5 via EV<mailto:[email protected]> To: [email protected]<mailto:[email protected]> Sent: Friday, December 12, 2014 2:24 AM Subject: [EVDL] EVLN: Should Extension Cords Be Used With Plugins? (don't get burned) 'If done right, correctly sized & used extension cables are OK' https://transportevolved.com/2014/12/09/reader-questions-answered-use-ex tension-cord-electric-car/<https://transportevolved.com/2014/12/09/reade r-questions-answered-use-extension-cord-electric-car/> Reader Questions, Answered: Should I Use an Extension Cord With an Electric Car? December 9, 2014 By Nikki Gordon-Bloomfield [images https://d2v41vkldk04pc.cloudfront.net/wp-content/uploads/2014/12/IMG_235 0.jpg<https://d2v41vkldk04pc.cloudfront.net/wp-content/uploads/2014/12/I MG_2350.jpg> Can you or should you use an extension lead to charge an electric car? https://d2v41vkldk04pc.cloudfront.net/wp-content/uploads/2014/12/Plug.jp g<https://d2v41vkldk04pc.cloudfront.net/wp-content/uploads/2014/12/Plug. jpg> (burnt/overheated plug-prong) This is the reason why automakers don't like you using portable charging equipment in untested outlets. https://d2v41vkldk04pc.cloudfront.net/wp-content/uploads/2014/12/J3504x2 336-08010.jpg<https://d2v41vkldk04pc.cloudfront.net/wp-content/uploads/2 014/12/J3504x2336-08010.jpg> This is an example of a poorly-built charging lead. https://d2v41vkldk04pc.cloudfront.net/wp-content/uploads/2014/12/Outlet. jpg<https://d2v41vkldk04pc.cloudfront.net/wp-content/uploads/2014/12/Out let.jpg> (burnt/overheated wall outlet) When there's a problem with a circuit, be it mechanical or electrical, there's a risk of a fire or overheating. https://d2v41vkldk04pc.cloudfront.net/wp-content/uploads/2014/12/J2160x1 440-09730.jpg<https://d2v41vkldk04pc.cloudfront.net/wp-content/uploads/2 014/12/J2160x1440-09730.jpg> If used correctly, extension cables shouldn't pose a threat. ] Here at Transport Evolved, we spend most of our time bringing you the latest news in the world of cleaner, greener, safer and smarter transportation. Sometimes, that means covering the latest press releases from major automakers. Sometimes, it means taking cars out for long test-drives to put them through their paces. And sometimes, it means answering reader questions. Today, we've been sent the following question by Phil, who is about to test out a Nissan LEAF for a few days to see if it's a good match for him and his family. He writes: I'm after some advice on the use of an extension lead to charge a car. I'm getting a Nissan Leaf on a 7 day trial and have no driveway, so would have to use an extension lead to charge it. I have seen Robert Llewellyn and some other people use one in videos, but for my trial it says not to use one. It wouldn't be an ordinary extension lead I would use, it is one I use when I go camping, and I have an adaptor to plug it into a mains socket, so with all the extra safety features of the extension, what do you think? Thanks for your question, Phil. It's one which we've been asked before, so we hope you won't mind if we turn this into a little piece of advice for other would-be plug-in owners who are asking the same question. In fact, charging with extension cords is one of the more common questions we're asked, so we think it's high time we offer our advice. Why its 'officially' not recommended To start, it's probably best to examine why most automakers advice against using extension leads when charging a car, and why many even discourage the use of a portable charging 'brick' or Electric Vehicle Supply Equipment (EVSE) instead of a dedicated charging station. It's common sense that an low to medium-power electric car charging station - portable or fixed - takes power from the mains electricity at either 110 volts or 230 volts, and feeds it into the charging inlet of your car. The type of fixed, permanent charging stations sold for home use are traditionally capable of between 3 kilowatts and 10 kilowatts of power transfer, depending on the type of charging station and the car you're wanting to charge. Portable charging stations usually provide between 1.5 kilowatts and 2.8 kilowatts, depending on the country you live in. In pretty much every country we can think of, charging stations which are permanently wired into a building's electronics are supposed to be installed and checked by a qualified electrician. In some places, those installations must also be certified as being both safe and up to appropriate wiring regulations or code. These checks not only check the quality of the installation, but also ensure that the electrical circuit feeding the charging station is appropriately rated for the amount of power the charging station and car will require. When it comes to a portable charging station however, the unit can be plugged into any power outlet, regardless of its age or condition. In the UK, where Phil is writing from, this means a household outlet which is rated at 230 volts and 13 amps. We should note however that most portable charging units pull between 6 and 10 amps to give at least minimal headroom between the maximum current drawn and the maximum theoretical current the outlet can provide. Assuming the wall outlet the portable EVSE is plugged into is correctly wired, has the correct power rating and has clean, no-corroded contacts, charging your car from it will have no problem. But if the contacts are corroded or poorly maintained, the cable joining the socket to the fusebox is of an incorrect rating, or there's some other lose connection somewhere between fuse box and EVSE, it makes it harder for electricity to pass through the circuit. When that happens, the cables and connectors can heat up. Since it's likely that most domestic outlets are correctly maintained and appropriately wired, automakers generally consider it okay to charge up from a wall socket in an emergency, since they can vouch for the condition of the charging cable and EVSE 'brick'. Include an extension cord of unknown origin, specification and condition, and most automakers get a little nervous. That's because you're not only adding an extra pair of connections to the circuit - which increases the risk of a poor connection somewhere - but you're physically making the electrical circuit longer. The longer the physical circuit, the more likely it is that the electricity will find it harder to flow along the cable. What's more, most extension leads aren't meant to work with the heavy, sustained loads called for when charging an electric car, and can easily heat up when pushed too hard. To avoid any unexpected problems, most automakers - especially when carrying out extended test drives - request people don't use extension cords. Reality is sometimes different You'll note we split the nitty-gritty explanation into its own part, and that's because as is often the case with life, the reality of using extension cords is somewhat different. Of those we know with plug-in cars, most carry some form of emergency extension cord with them on longer trips or when visiting friends and family who don't have a dedicated charging station. Instead of being a cable they've found in the back of the garage, these owners will take their time and buy a cable which is approved and rated for use on higher electrical loads. In the UK, where it's okay to still wire your own extension leads, some owners even make their own heavy-duty extension cords, buying appropriate heavy-duty 13-amp sockets and flexible, heavy-duty 'Arctic' cable that is rated to carry an electrical load far higher than the EVSE will pull. In these cases, the use of an extension cord isn't all that risky - although we should note there is always some inherent risk in adding extra physical connections in the circuit - and when used apporpriately with a well-maintained, tested power outlet, there shouldn't be a problem. Phil's situation In Phil's case, we note that the cable he's proposing to use is one which is rated to carry far more than the current the portable EVSE will use , and even makes use of the CE 16-amp (blue) plug found at camp sites across Europe on one end. As well as being a larger connector - which lowers mechanical and electrical stresses on the plug and socket - the cable itself is rated to carry 25 amps, far more current than the EVSE will pull. If someone were to use this extension cord to charge an electric car, it would be one of the better extension cords we've ever seen used for the purpose. Here at Transport Evolved, all of our plug-in owning staff have used extension cords from time to time to charge a plug-in car. And for the most part, we've not had any problems. But we also know people who have been unlucky through using an unfamiliar outlet, or whose portable EVSE has pulled out of the attached plug, causing an electrical short and heating. As a consequence, you should NEVER use a portable charging unit with an unknown power outlet or an unknown extension cord, and you should only really use portable charging units as a temporary or emergency solution in preference to a dedicated charging station. DISCLAIMER: We're not condoning the use of extension cords to charge your plug-in car. Nor are we saying bad things will happen if you do. We're saying that yes, there are risks and yes, when used with the correct precautions, you shouldn't have a problem. Transport Evolved accepts no responsibility or liability for those who choose to use an extension cord after reading this discussion. Instead, the onus is on each individual to accept all liability when using a portable EVSE - with or without an extension lead. [(c) 2014 Transport Evolved] For EVLN posts use: http://evdl.org/evln/<http://evdl.org/evln/> http://www.evdl.org/archive/index.html#nabble+template%2FNamlServlet.jtp %3Fmacro%3Dsearch_page%26node%3D413529%26query%3DEVLN%2Bbrucedp2%26days% 3D0%26sort%3Ddate<http://www.evdl.org/archive/index.html#nabble+template %2FNamlServlet.jtp%3Fmacro%3Dsearch_page%26node%3D413529%26query%3DEVLN% 2Bbrucedp2%26days%3D0%26sort%3Ddate> http://www.detroitnews.com/story/business/autos/2014/12/02/merkel-backs- incentives-germanys-electric-car-goal/19792255/<http://www.detroitnews.c om/story/business/autos/2014/12/02/merkel-backs-incentives-germanys-elec tric-car-goal/19792255/> Chancellor.de Merkel backs EV incentives to reduce emissions http://postandparcel.info/63561/news/deutsche-post-dhls-electric-new-dea l/<http://postandparcel.info/63561/news/deutsche-post-dhls-electric-new- deal/> Deutsche Post DHL acquires streetscooter.eu EVs http://www.pressherald.com/2014/11/30/josh-christie-on-behalf-of-all-win ter-sports-enthusiasts-thanks-a-plenty/<http://www.pressherald.com/2014/ 11/30/josh-christie-on-behalf-of-all-winter-sports-enthusiasts-thanks-a- plenty/> 2 EVSE & 803 PVs @Greenwood ME's Mt. Abram> an eco-future ski-resort + EVLN: GBP32k Tesla-Developed Mercedes-Benz B-Class EV Is Now on Sale {brucedp.150m.com} -- View this message in context: http://electric-vehicle-discussion-list.413529.n4.nabble.com/EVLN-Should -Extension-Cords-Be-Used-With-Plugins-don-t-get-burned-tp4673011.html<ht tp://electric-vehicle-discussion-list.413529.n4.nabble.com/EVLN-Should-E xtension-Cords-Be-Used-With-Plugins-don-t-get-burned-tp4673011.html> Sent from the Electric Vehicle Discussion List mailing list archive at Nabble.com. _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub<http://www.evdl.org/help/index. html#usub> http://lists.evdl.org/listinfo.cgi/ev-evdl.org<http://lists.evdl.org/lis tinfo.cgi/ev-evdl.org> For EV drag racing discussion, please use NEDRA (http://groups.yahoo.com/group/NEDRA<http://groups.yahoo.com/group/NEDRA >) -------------- next part -------------- An HTML attachment was scrubbed... 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