LiFePo4 charger + $98 generator = not good.

1000w

1 kW
Joined
Apr 26, 2008
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441
Location
Western Australia
I went to a farm near York WA this weekend for a dirt track motor bike race. There was the full spectrum of ICE bikes there from Harleys to Honda postie bikes.
I took my Giant Reign along to represent the EV world. http://www.endless-sphere.com/forums/viewtopic.php?f=28&t=34451&start=75
As there was no power there I took a generator, this could output only 550w continuously and my 73 volt 8 amp charger uses 650w from the mains power.
A quick test at home seemed to go fine, however at the event after about 45 mins the charger went dead and no longer works, no LEDs or fan when hooked up to 240v mains.
Any clever guys know what components I have damaged?
Here's a vid I did with my tricopter, gives an idea of the track layout. http://www.youtube.com/watch?v=3mJZDddwjMc&feature=youtu.be
Also, I was able to lap as fast as any of the ICE bikes, there was a few diehard ICE boys who were very impressed. I gave lots of laps on the Ebike away to help spread the EV word.
Sorry no vid of my bike racing. :(
Cheers,
Matt
 
check to see if the fuse on the AC input plug is open. if it seems ok, then when you have normal line voltage at home, measure the 240V AC voltage on the back of the AC input plug or the place where the wires are soldered to the pcb.
 
Can't help with the charger Matt but dam the tricopter footage is way cool, next time you head over bring the chopper, we can duck across the road, I'll lap around the park on the ebike you follow with chopper be good footage fo-s ho!

KiM
 
we should be able to isolate the problem by working through the circuit, one step at a time. if there is 240V to the rectifier bridge then it should have 340V across the two switching mosfets in series. so that is next thing to test.
 
Thanks Kim, I'll bring the tricopter up some time for sure.
Thanks dnmun, this is the sort of questions I need to get to the bottom of this problem.
I'm not sure which component the rectifier bridge is, so I don't know which caps to check.
Here are some photos to help identify what's what.
charger4-1.jpg

charger1-1.jpg

charger3-1.jpg

charger2-1.jpg
 
then measure the voltage between the collector of the top switching transistor and the emitter of the lower switching transistor. the top switcher is next to the small transformer and the lower one is where that wire from the switch runs down to the base resistor of the lower transistor.
 
I started testing the voltage across the switching transistors, not really knowing what I was doing, then there was a loud pop.
The front face of the top switching transistor next to the small transformer blew off. :eek: :(
 
Sounds like in addition to the original problem, he blew the totem pole transistors on the gate drive transformer.

These are not the most robust design unfortunately. If you get really stuck, I am located in Aus and I can take a look at it for you - I've fixed a few. I still don't like them though :)
 
OK, I've given up and buying a new one.
I think the guys who offered help assumed my electronics skills were much higher than they are.
Cheers,
Matt.
 
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