Ray, It is good to avoid using a retractable power cord in (partial) retracted position because of the many turns of wire, all held snugly against each other and adding up the heating of the total assembly.
It is quite safe to use a retracted power cord if only a small fraction of the max current rating is used. Some retractable power cords list the max allowed power when in retracted position. In Europe it is common to find retractable power cords on such appliances as vacuum cleaners since the voltage is double that ni USA, so current is often as low as 4 Amps for a 1000W vacuum, while in USA it is common to see a 12A rating for cheap vacuums and the cord is wound up on the outside of the vacuum. Wind-up extension cords with 4-way outlets on top are also common. All retractable cords come with a warning that it should not be used at full power in retracted position. Ig nore that warning and you will find out how the resistive heating will cause a cord to melt if you unexpectedly draw more power than the (partially) retracted cord can handle. The NEC also has different max current ratings between a single conductor or multiple conductors lying against each other. Cor van de Water Chief Scientist Proxim Wireless Corporation http://www.proxim.com Email: [email protected] Private: http://www.cvandewater.com Skype: cor_van_de_water XoIP: +31877841130 Tel: +1 408 383 7626 Tel: +91 (040)23117400 x203 -----Original Message----- From: [email protected] on behalf of rayfellow Sent: Sun 7/7/2013 9:12 PM To: [email protected] Subject: Re: [EVDL] Retractable Power Cord 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. -- View this message in context: http://electric-vehicle-discussion-list.413529.n4.nabble.com/Retractable-Power-Cord-tp4664098p4664099.html Sent from the Electric Vehicle Discussion List mailing list archive at Nabble.com. _______________________________________________ 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) _______________________________________________ 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)
