That is a weird response. Did I not make my lack understanding, and enjoyment of floundering around clear?
On Fri, Apr 18, 2014 at 2:13 PM, Dennis Miles <[email protected]> wrote: > Michael, Your ego is boasting,"I can design my own" but, your statements > show IMHO the fact is that you don't know "Real World Design." Perhaps you > should build your own and invest a dollar in your own design. Then test it > on your vehicle and brag about it. But, quit the argument, because Lee's > bridge will work and your design is only in your imagination and dreams. > Put up or shut-up! > > *Dennis Lee Miles * > > *Director **E.V.T.I. Inc.* > > *E-Mail:* *[email protected]* <[email protected]> > > > > > > > On Fri, Apr 18, 2014 at 1:48 PM, Michael Ross <[email protected] > >wrote: > > > My packs are 16 (or possibly 17) cells of LFP. My highest charge voltage > > is 60VDC, so a half pack would be OK - always below 30V. CMOS logic and > > handle that which is convenient. > > > > Should be interesting. > > > > > > On Fri, Apr 18, 2014 at 1:31 PM, Lee Hart <[email protected]> > wrote: > > > > > Michael Ross wrote: > > > > > >> I will probably be implementing a DC battery system for lighting and > so > > on > > >> so I can get op amp power from there. > > >> > > > > > > I don't know about your lighting system, but in an EV, the pack is > > > isolated from ground. The voltages you want to measure are "floating" > and > > > not ground referenced. You can't power the comparators from a grounded > > 12v > > > system. You either needed a 12v DC/DC converter with isolated output, > or > > a > > > HVDC-to-low voltage power supply to power the comparators. > > > > > > > > > Or there is already a converter to > > >> 12V on it. I would not use TTL if I can get around it - because it is > > >> noise vulnerable. I would likely resort to some optos if noise gets > > >> difficult. > > >> > > > > > > From a "do this task" POV, an op amp comparator is exactly the right > > >> function. > > >> > > > > > > Technically, the function needed is a window comparator. This uses two > > > comparators. One detects a voltage above the reference, and the other > > > detects a voltage below the reference. But you can get two (or more) > > > comparators inside a single chip (LM393 for example). > > > > > > However, IC comparators are intended for voltages under 30 volts. It > > takes > > > a lot of parts to use them to compare higher voltages. > > > > > > If the difference between the two halves is too great then it warns. > > >> if the difference is intermittent then the indication stops. I think > > >> I may like this better than a slowly increasing brightness > > >> > > > > > > If you want a hard "digital" on/off indication, use the LED in an > > > optocoupler in place of the red LED in the Batt-Bridge. Use the output > of > > > the optocoupler to switch some "digital" device, like logic gate or > > relay. > > > Or, there are optocoupler with built-in hard-switching digital outputs > > that > > > could directly switch something on/off. > > > > > > But in any case... start by precisely defining the problem you wish to > > > solve *without* assuming a solution. Exactly what must the output do? > > Work > > > backwards from there. > > > > > > -- > > > If you're not stubborn, you'll give up on experiments too soon. > > > And if you're not flexible, you'll pound your head against the wall > > > and you won't see a different solution to a problem you're trying > > > to solve. -- Jeff Bezos > > > -- > > > Lee Hart's EV projects are at http://www.sunrise-ev.com/LeesEVs.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) > > > > > > > > > > > > -- > > 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/20140418/306305a4/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) > > > > > -------------- next part -------------- > An HTML attachment was scrubbed... > URL: < > http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20140418/ca5109de/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) > > -- 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/20140418/7ee7c5fb/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)
