The statement shown below was posted. Can someone answer the question does a 6.6KW charger demand all or nothing?
I would think that all well designed, UL or CE listed chargers are designed for an input voltage of 100 - 264VAC (sometimes referred to as universal or international input). If the 6.6 KW charger is a demand all charger, the input current must increase at 120VAC vs 240VAC. For example, Output KW = 6.6 KW , Input voltage = 240VAC, Efficiency = 80%. Then input current = (6.6KW / 0.8) /240VAC = 34A. For 120VAC input, the input current = (6.6KW/0.8)/120VAC = 69A. This is a rough calculation .... I know have have not included power factor, current limiting, etc; however, it shows my point. If I connect a 6.6KW charger to 120VAC, the input current increases because the output is fixed. This being said, I think some if not all onboard EV chargers adjust the charger out based on the input voltage thus maintaining a 16A maximum input for 120VAC. I think this is the function of the 1KZ output signal. It tells the car charger the maximum current it can drawn from the EVSE. Th e charger then adjust its PWM duty cycle to limit the output power of the charger. This means that a car with a 6.6KW charger connected to 120VAC EVSE only outputs approximately 120VAC * 16A * 0.8 eff = 1.5 KW. ________________________________ From: EV <[email protected]> on behalf of Bill Dennis via EV <[email protected]> Sent: Saturday, September 24, 2016 9:58 AM To: 'Willie2'; 'Electric Vehicle Discussion List' Subject: Re: [EVDL] Another J1772 L2 purchase I think that the J1772 spec has a 1kHz signal on one of its lines, the duty cycle of which specifies the maximum charging current. So the device you're looking at probably has a duty cycles of 25% or so, for around 15A. Bill -----Original Message----- From: EV [mailto:[email protected]] On Behalf Of Willie2 via EV Sent: Saturday, September 24, 2016 10:29 AM To: Electric Vehicle Discussion List Subject: Re: [EVDL] Another J1772 L2 purchase On 09/24/2016 11:13 AM, Lawrence Rhodes via EV wrote: > Warning Will Robinson. The EVSE you selected are not good for modern > EV's. Only 3.3kw. They may not work with 6.6kw chargers. Lawrence > Rhodes It had not occurred to me that a 6.6kw charger would demand "all or nothing". Is that a possibility? That is, might a Leaf with a 6.6kw charger refuse to charge unless it was offered the full 6.6kw and would fail to charge at an EVSE that offered only 3.3kw? _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org Read EVAngel's EV News at http://evdl.org/evln/ Please discuss EV drag racing at 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 Read EVAngel's EV News at http://evdl.org/evln/ Please discuss EV drag racing at 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/20160924/cbe063b3/attachment.htm> _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org Read EVAngel's EV News at http://evdl.org/evln/ Please discuss EV drag racing at NEDRA (http://groups.yahoo.com/group/NEDRA)
