Hello Wayne, Using a PFC charger as I do, I have to turn down the current knob on the charger before I turn it on and turning it off.
There is a bank of capacitors in this charger, that the battery pack keeps the capacitors charge up if you leave the charger connected all the time. Disconnecting the charger will cause a current kick back. I found this out when I disconnected any one of my battery links which cause a spark which could be dangerous if there is any battery fumes. It is also recommended to completely isolated the main battery pack from the motor controller and DC/DC. The battery charger voltage is higher than the normal voltage of the battery pack, will suppress this voltage on to the motor controller even if the main contactor is off. The negative side of the battery pack is direct connected to the controller shunt and directly to the motor. This negative voltage goes through the motor and back to the motor controller. I use two contactors which are the same rating of the main contactor that are use to disconnected the battery pack from the controller. I use the ignition ON switch to turn these contactors on and than the start switch to turn on the main contactor. You cannot turn all these contactors on with the same switch because it will cause a fault which is cause by one contactor coming on a microsecond late. Also I had this negative current conduct over the brush dust in the motor to the chassis of the vehicle which will cause a surge of battery charger current. First, make sure the charger current knob is turn down when turning off or on the charger. Next, use a fuse that is design for interrupted starting loads. A standard fuse that has a rating of 10 amps actually will take 10 x 1.25 = 12.5 amps. A surge type fuse as a Buss Fusetron, will take up to 30 amps surge during a start up. Roland ----- Original Message ----- From: Wayne Krauth<mailto:[email protected]> To: [email protected]<mailto:[email protected]> Sent: Tuesday, July 30, 2013 1:50 PM 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<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://www.evdl.org/help/index.html#usub> http://lists.evdl.org/listinfo.cgi/ev-evdl.org<http://lists.evdl.org/listinfo.cgi/ev-evdl.org> For EV drag racing discussion, please use NEDRA (http://groups.yahoo.com/group/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/20130730/14934473/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)
