Wayne, The reason is simple and has been discussed a couple times on this list. 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)
