My question relates to orientation and ground clearance. Now I like about 8.5 inches of completely clear ground clearance, that way it can clear a 8x8x16 cement block, and most debris is smaller than that. The other question is one of orientation... Why does everyone want to put the unit in the pavement under the car? Why not put it in front of the car with a format twice as large as a front license plate. (12x12 inch ) and a box like structure in front of the parking space, it should be readily possible to attain alignment within half an inch and nominal contact with rubber rails to catch the front of the car without marring. The details become much simpler at 440 Hz also...and that eliminates induced voltages at beyond 2 inches... Thinking out of the box is interesting...
Dennis Lee Miles (EVprofessor) *Founder: **EV Tech. Institute Inc.** (www.evti.org <http://www.evti.org>) * *E-Mail:* *evprofes...@evprofessor.com* <evprofes...@evprofessor.com> *Phone #* *(863) 944-9913* in Central Florida (Office hours: 12:00 Noon to 10:00 pm, New York time) On Sat, Jul 19, 2014 at 6:11 PM, Peter C. Thompson via EV <ev@lists.evdl.org > wrote: > Hi Lee, > > Part of the long, long discussion covers this. We have a list of common > metal items (along with size and material) that must be detected. There are > some other standards that EV charging will have to conform to, since we > will need to prevent overheating that can cause human injury. > > Some of the scenarios that we have: > * metal left on the pad before charging (coins, cans, keys, metal > foil, etc), > * metal blowing onto the pad during charging (same list), > * living objects moving near to the charging area. > The list is not complete yet, but I'm hoping we'll be done with it by the > end of the year. It is slow going since we need to negotiate with > companies worldwide. > > Cheers, Peter > > > On 7/19/14, 8:53 AM, Lee Hart via EV wrote: > >> Peter C. Thompson via EV wrote: >> >>> I've just spent an entire week working with the standard >>> responsible for this, so all of this is VERY fresh in my mind. :) >>> >> >> Excellent! I'm delighted to see your company thinks it is important. >> Though, I still worry about "unintended consequences". >> >> When I was working with a high-power switchmode power supply, one of the >> techs happened to be wearing a wristwatch with a metal band. He reached >> over the supply to adjust something, and his wrist watch band got hot! >> >> The flux leakage from the 50kw transformer was tiny -- maybe 0.1%. But >> 0.1% of 50kw is 50 watts -- easily enough to overheat the band. There was >> no observable change in the operation of the supply at all. If he hadn't >> jerked his hand away, he would have gotten burned! >> >> I've heard of similar situations with people wearing rings or other metal >> jewelry. There are also cases of burning up parts or traces on PC boards in >> phones etc. due to stray EM fields. Even a tiny power loss that's too small >> to detect can have serious consequences. >> >> > _______________________________________________ > 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) > > -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20140719/82a638fe/attachment.htm> _______________________________________________ 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)
