"With a setup like that, however, you have to use an interlock so you can't apply power to the heating element unless the blower is running. If it overheats, the safety cutoff, which is designed for AC, is apt to weld closed on DC. (Guess how I learned that lesson.)"
I just finished wiring the thermal fuses in my ceramic heaters in series with the contactor coil so that the DC will be shut down by the contactor's main contacts. I was trying to sort out an air-flow switch that would inhibit the contactor if the fan quit spinning, but ran out of time on that. All the microswitches I had on hand took too much pressure to operate, such that the slowest fan speed would never switch. I'm thinking optical gap detector for the future. On Sun, Oct 13, 2013 at 2:24 PM, EVDL Administrator <[email protected]> wrote: > On 13 Oct 2013 at 13:53, David Chapman wrote: > > > In the ill fated Twike ... > > Ill-fated? > > http://www.twike.com/ > > Looks like it's still hanging in there. > > It's a tad pricey, though, at 23237 euro with the smallest battery. > > > they used a pair of Braun hot air styling wands. > > I've used pistol style hair dryers. They're annoyingly noisy, but if you > can figure a way to keep them aimed at the windshield they do the job. > > You very definitely need a contactor or a substantial relay to turn them > off > and on. > > I've also cut the "barrel" off such a hair dryer and fed it from a much > larger DC motor blower. That reduced the noise quite a bit. > > With a setup like that, however, you have to use an interlock so you can't > apply power to the heating element unless the blower is running. If it > overheats, the safety cutoff, which is designed for AC, is apt to weld > closed on DC. (Guess how I learned that lesson.) > > In my C-car I also used a box type space heater with a rewired nichrome > element and the AC motor replaced with a DC motor. Alternatively, you > could > power the heater's original AC fan motor with a small 12v input inverter. > > There are also no doubt many small ceramic element portable heaters that > could be used this way, though I'm not sure how many could be wired for > lower voltage EVs (96v and less). > > David Roden > EVDL Administrator > http://www.evdl.org/ > > > _______________________________________________ > 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/20131013/ad702f39/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)
