Re: [EVDL] charging numbers
Rush, The *power* is 7.2 kW and this means 7200W / 240V = 30A The *energy* is 7.2 kW times 4 hours = 28.8 kWh See how the units multiply just like the numbers? 7.2 x 4 = 28.8 kW x h = kWh You can also divide (work the other way) so that the energy divided by the time is power: 28.8 / 4 = 7.2 kWh / h = kW Hope this clarifies! Cor van de Water Chief Scientist Proxim Wireless office +1 408 383 7626 Skype: cor_van_de_water XoIP +31 87 784 1130 private: cvandewater.info www.proxim.com This email message (including any attachments) contains confidential and proprietary information of Proxim Wireless Corporation. If you received this message in error, please delete it and notify the sender. Any unauthorized use, disclosure, distribution, or copying of any part of this message is prohibited. -Original Message- From: EV [mailto:ev-boun...@lists.evdl.org] On Behalf Of Rush Dougherty via EV Sent: Monday, May 25, 2015 1:40 PM To: EVDL Subject: [EVDL] charging numbers The e-Golf has a 7.2kW charger on board and L2 charging will take 4 hrs. So does that mean that it averages 7.5A per hour? My logic - 7200 watts / 4 hrs = 1800 watts per hour, 1800 watts per hour / 240v = 7.5 A per hours. I know that I'm doing something wrong here but I just can't see it. Some help please. Rush Tucson AZ ___ 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) ___ 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)
Re: [EVDL] charging numbers
With a 24kwh battery pack it takes 4 hours for a realistic 7.5kw charger that actually charges at 6kw to charge a pack that is about 80% depleted. -- View this message in context: http://electric-vehicle-discussion-list.413529.n4.nabble.com/charging-numbers-tp4675762p4675764.html Sent from the Electric Vehicle Discussion List mailing list archive at Nabble.com. ___ 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)
Re: [EVDL] charging numbers
On 25 May 2015 at 13:40, Rush Dougherty via EV wrote: So does that mean that it averages 7.5A per hour? There's no such unit as amps per hour or watts per hour. That's like saying gallons per minute per hour. It's a meaningless unit. Amp-hours per hour and Watt-hours per hour are technically real units, but they're normally called amps and Watts respectively. Think of the slash that means per in AH/h as a division sign. The hour terms cancel each other out and you get just amps, because hour / hour == 1. If the EV has a 7.2kW charger and charging takes 4 hours from 100% DOD, that means that (neglecting losses) the battery capacity is (4 hours * 7.2 kilowatts) == (4 * 7.2) (kilowatts * hours) == 28.8 kilowatt hours. David Roden - Akron, Ohio, USA EVDL Administrator = = = = = = = = = = = = = = = = = = = = = = = = = = = = = EVDL Information: http://www.evdl.org/help/ = = = = = = = = = = = = = = = = = = = = = = = = = = = = = Note: mail sent to evpost and etpost addresses will not reach me. To send a private message, please obtain my email address from the webpage http://www.evdl.org/help/ . = = = = = = = = = = = = = = = = = = = = = = = = = = = = = ___ 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)
