Hi Cor On Jul 30, 2013, at 1:16 PM, Cor van de Water <[email protected]> wrote:
> Wayne, > The reason is simple and has been discussed a couple times on this list. I don't think it has; I think you are referring to the case of where people (like me) were blowing fuses on their Dc-DC converter; but not on the charger output side. This is an interesting theory though. In practice, I haven't hit it, and I have a very ripple prone Controller (Netgain Warp Drive). I have the same charger as the poster: PFC-30, and haven't blown the output fuse. I can check and see what fuse I'm using. corbin > The fuse blows, because the controller is causing a large ripple current > and the output caps of your charger are trying to smooth that ripple, > leading to large ripple current through the output fuse. > In theory, removing the output caps would solve this problem, > but it might be simpler and in practice more likely to give > good results to add a diode to the output of the charger, so it > can only send current into the pack and not allow the > controller to use the output caps for smoothing the controller ripple. > > (It is even possible that the controller causes the charger caps to blow > and so destroy the charger without you even being plugged in, simply > from the ripple that the controller produces and the charger caps > are being subjected to - the resulting ripple current is probably well > beyond their rating, so you could be damaging those caps while driving. > > I have two Schottky diodes that are heatsink-mountable (watch out - the > mounting is also the electrical connection, so make sure to mount them > on an isolated base) > These are 200A, 400V so should be plenty for your charger output. > Reason I can't use them is that these are half of a dual diode package > and I have blown one diode, the other is still fine, my applicatoin > needs both to sustain 400A, so just give me your address and I will > ship a diode to you. The blown half is a dead short, so your > multimeter will tell you which half is good and which is bad. > > Here is a new one on Ebay (403CNQ400): > http://www.ebay.com/itm/230918736569 > > Cor van de Water > Chief Scientist > Proxim Wireless Corporation http://www.proxim.com > Email: [email protected] Private: http://www.cvandewater.info > Skype: cor_van_de_water Tel: +1 408 383 7626 > > > -----Original Message----- > From: [email protected] [mailto:[email protected]] On > Behalf Of Wayne Krauth > Sent: Tuesday, July 30, 2013 12:51 PM > To: [email protected] > Subject: [EVDL] Blown output fuse (was: First time PFC charger > setupquestion) > > The output fuse on my PFC30 appears to be occasionally blowing while I > am > driving. The car completes its charge cycle ok, and can top up the > pack > if the car has not been used after charging, so I know it's ok before > driving. > > If it is driven with motor & battery currents limited to 400A or 500A, > there > is usually no problem. If the current limits are increased to 700A or > more, and that current is used during the drive, then the charger output > fuse *might* be blown when I next try to charge. > > One time I heard the fuse pop when starting to turn up the charger > current, > so the fuse was not blown until charge time. > > I have also checked the fuse after a drive but before plugging in the > charger, and have found it to be blown. > > At first I thought that maybe there is a HV isolation fault between the > traction pack and the car frame. A voltmeter from chassis to voltage > points > in the pack shows HV DC, but the voltage quickly drops to zero (well > under a > minute). I presume that this is a capacitive charge that discharges > through the voltmeter. Is this behavior expected or does it indicate > a > problem? > > The traction pack has six 40V batteries, and is connected directly to > the > charger, motor controller, and DC/DC. Should I use a diode between the > traction pack and the charger? Or a inrush current limiter? > > Looking for suggestions on how to determine the source of the blown fuse > problem. > > Thanks, > > Wayne Krauth > evalbum.com/3567 > > > > -- > View this message in context: > http://electric-vehicle-discussion-list.413529.n4.nabble.com/First-time- > PFC-charger-setup-question-tp4656968p4664498.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) > > _______________________________________________ > 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)
