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Though retractable and reel cord terms are used interchangeably, I define retractable cords as extension cords that are curled up to act like a spring, and reel cords as extension cords as those that are on a spring loaded reel, so that when you unplug and let go, the cord pulls itself back onto the reel. You did not state how much current you will be pulling from a level-1 outlet, and what type of charger you are using. I will assume a worst case scenario: you will be pulling the most you can from a 20A outlet (16A), and your on-board charger has a low pfc/inefficient-design (i.e.: a K&W BC-20, with lots of current spikes that heat up cords). As a long time user of power cords (I had a whole back seat full of extension cord in my S-10 Blazer conversion EV), I can tell you even with the extension cord out flat on the ground, under the vehicle, and out of the sun, pulling 16A through a 12 or smaller gauge cord will heat it up, and cook the: cord, plug, and receptacle. As posted, most retractable or reel cords are too small a gauge to handle any serious EV charging current. If all you were pulling was 5A, it might be OK. Do not go by the rating on the product. They do not test for EV use which really does draw the maximum current over several hours of use. Example: I had a 25 foot 12 gauge extension cable I specifically used with my Zivan NG5 on-board charger. See http://brucedp.0catch.com/blazer/blazer020504-001.jpg It would draw 16+A on 240VAC at home. Though the cord was laid out flat (so it had air-cooling), over time it would heat up. With repeated use, the outer covering cooked/shrank to where the covering showed the internal twisted wire shape. Upon my routine checking of my cords, I saw discoloration on the plug (the prongs were beginning to darken, like they were over heating). Cutting back on the wires at the plug and receptacle, showed the cord's wires were also showing overheating (they were dark too). So, even with a 12 gauge extension cord that has air-cooling, pulling 16+Amps through it will over tax it's design. Also know, that your idea is not new. On all the conversions I saw at EAA Chapter meetings, over time with daily use, the spring in the reel gave out, and it stopped retracting. So plan to replace the reel cord regularly. If you still have your heart set on getting one anyway, then be sure to search using keywords retractable 12 gauge cord I am not recommending this one, but I found http://www.specialized.net/Specialized/Bayco-SL800-TripleTap-Extension-Cord-w-Retractable-Reel-30-3693.aspx If the one you purchase comes with molded plugs and receptacles, I recommend that you spend the extra money and replace them with standard plugs and receptacles as those are more robust and can handle/dissipate heat better. ... Another scenario would be a Production plugin that uses their level-1 EVSE that they carry with them. Those only draw 12A, have a fairly high pfc, thus I believe should work fine using a 12 gauge extension cord. All the L1 EVSE I have seen charging using a 12 gauge non-reel extension cord, have not heated up the cord (I used my hand to feel the amount of heat. The cords were at most tepid -warm, but none that were hot). {brucedp.150m.com} - On Mon, Jul 8, 2013, at 06:03 AM, Lee Hart wrote: > rayfellow wrote: > > The trouble is power cords should not touch each other or cross over each > > other because of heat. A friend burned his house down because of fire caused > > by overlapping power cords. I suspect manufacturers hesitate to offer such > > an item for fear of the liability. > > I can second that. I know of a nice EV conversion where the owner used a > cord on a reel for charging. There were plenty of warnings on the > packaging; "unreel cord before use" etc. But he ran 10-15 amps through > it to charge his EV with the cord still all reeled up. The cord melted, > shorted out, and luckily tripped the breaker before a fire started. But > the cord and its reel were completely destroyed. > > It is *possible* to de-rate the cord enough so it won't overheat even if > left coiled up. But I think you would wind up needing such an oversized > wire that it would make the reel impractically large, heavy, and > expensive. > > They do make industrial-strength coil-cords. These would be a more > practical way to make a self-coiling charging cord. - -- http://www.fastmail.fm - Or how I learned to stop worrying and love email again _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org For EV drag racing discussion, please use NEDRA (http://groups.yahoo.com/group/NEDRA)
