Michael, you said, "Doesn't AC essentially has a lesser duty cycle at at the peak voltage - which is why RMS ends up being a more useful number? The DC has a 100% duty cycle - isn't this a mitigating factor when comparing them? " The RMS of DC equals the peak and the RMS of a sine wave in AC is 0.707 times peak. but they are equivalent in making heat, (For magnetic force operated device the effectiveness is related to the average of the sine wave which is 0.636 times peak. The design consideration is the insulation voltage breakdown and semiconductor component breakdown voltages must be adjusted in the specifications for the larger peak voltage required to do a comparable amount of work.
*Dennis Lee Miles * *Director **E.V.T.I. Inc.* *E-Mail:* *[email protected]* <[email protected]> *Phone #* *(863) 944-9913* Dade City, Florida 33523 USA On Wed, Jun 25, 2014 at 11:51 PM, Michael Ross via EV <[email protected]> wrote: > Doesn't AC essentially has a lesser duty cycle at at the peak voltage - > which is why RMS ends up being a more useful number? The DC has a 100% > duty cycle - isn't this a mitigating factor when comparing them? > > > On Wed, Jun 25, 2014 at 10:32 PM, Robert Bruninga via EV < > [email protected]> > wrote: > > > >> "I thought I²R heating was greater for DC. > > > > > NO, if the power factor is perfect, the losses due to current > > > squared times circuit resistance, are... the same for AC and DC, > > > > I can see that my original statement was confusing. What I meant was > that > > for the same conductor and same I^2R loss, DC can deliver nearly 40% more > > power because the DC line can operate at the PEAK voltage rating of the > > line, whereas the AC line only delivers that same current power at RMS > > voltage, not peak. 40% increase is worth doing for long point-to-point > > transmission (with no taps) > > -- > 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/20140625/462bc6bc/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/20140626/59686c05/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)
