Lee and Jan, Thank you for the helpful and and instructive responses. I don't know enough to ask good questions yet. Need to flounder and release some smoke a bit. It is just the way I do it.
On the 60V and above bit. I simply don't have a power supply for more than 60V. So 60/16 will get me 3.75V/cell; 60/17 = 3.53V. No danger of charging beyond the circuits abilities, but noise.... My assumption is the batteries are such a large capacitance that I won't see spikes of note. But the little motor is DC....inductive spikes? http://em3ev.com/store/index.php?route=product/product&product_id=52 It is not clear to me about the rating. It develops between 500W and 1000W. Depending on the controller and number of turns. It is hard to glean the truth looking at the specifications. I maintain 28mph on flats with 26" tires, and I turned down the peak amps and acceleration rates to make me work harder. They call for less than 30A, but I am not sure what it really is doing. It uses a Kelly Controller (RC stuff) KBS series. These are VFD's, I believe. Which can be noisy. http://kellycontroller.com/mini-brushless-controller-kbs12v-72v-c-60.html I think this is the one: http://kellycontroller.com/kbs48051x25a24-48v-mini-brushless-dc-controller-p-503.html The description says Low EMC. Not very useful. Do inductive spikes make it out of the controller to the batteries? Is there radiated EMI? I think if I am careful with wiring - no loops and parallel conductors to create coupling - I may have no noise trouble. On Fri, Apr 18, 2014 at 3:20 PM, Jan Steinman <[email protected]> wrote: > > From: Lee Hart <[email protected]> > > > > ... IC comparators are intended for voltages under 30 volts. It > > takes a lot of parts to use them to compare higher voltages. > > It actually isn't that bad. A simple voltage divider (two resistors) can > do it. > > Another possibility is a zener diode to eat up the excess voltage. > > The problem with both these techniques is variance, which you can deal > with via a trim pot. > > Another problem might be temperature sensitivity, but if you use similar > components on both arms, the temp coefficients should cancel each other out. > > :::: The primary impediment to community is the stranglehold that > hierarchical corporate-driven models of employemnt have on individuals. > They so completely drain the life-energy of people in endeavors that are > only marginally related to survival or fun that when people return home at > the end of the day they're exhausted, suitable only for a few hours of TV > and dropping into bed. -- Thom Hartmann > :::: Jan Steinman, EcoReality Co-op :::: > > _______________________________________________ > 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) > > -- Put this question to yourself: should I use everyone else to attain happiness, or should I help others gain happiness? *Dalai Lama * Tell me what it is you plan to do With your one wild and precious life? Mary Oliver, "The summer day." To invent, you need a good imagination and a pile of junk. Thomas A. Edison<http://www.brainyquote.com/quotes/quotes/t/thomasaed125362.html> A public-opinion poll is no substitute for thought. *Warren Buffet* Michael E. Ross (919) 550-2430 Land (919) 576-0824 <https://www.google.com/voice/b/0?pli=1#phones> Google Phone (919) 631-1451 Cell (919) 513-0418 Desk [email protected] <[email protected]> -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20140418/07b1e2d8/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)
