srdjanmax

I have a ebike controller rated for 48v but my battery is 60v. Because of over heating I decided to cut the controller open, put it in a fuse box, install a couple of fans on the box, and run it like that. So I did all of that, but the motor started spinning backwards. I switched green and blue phase wires and that did the trick. But I would still like to know what I messed up on the controller? I have a second controller and everything works as it should with that one. So I messed up something probably while cutting the top open. Anyone has any ideas? I'm affraid that it will reverse the polarity while I'm riding the bike, which will make me crash. Any help is appreciated.

2old

Maybe (I said maybe) it's related to the fact that many 48V controllers are for 13s (48V nominal, 54.6V fully charged) batteries but will accommodate 14s (52 nominal, 58.8 fully charged), but not 15s (63V fully charged). Check inside the controller.

srdjanmax

No, I dont think I've explained it well. Even with 60v battery and phase wires connected/matched by color, the motor was spinning as it should - forward. Only after I cut the controller open (I removed top, front and back, to allow for air circulation) the motor started spinning backwards. As I mentioned, I corrected the problem by reconnecting phase wires, blue to green, green to blue. Yellow stayed connected to yellow. My question is what could I have done to mess up the phases. I was not doing any soldering or anything similar. I just removed the top by cutting it off (back and front were held by screws so that was easy to open). I do not see any visible mechanical damage on the board. But something happened when I was cutting of the top with an oscillating tool. Any ideas what could happen to mess up the phases?

2old

I think you explained it well, but I didn't analyze it well. I've never experienced anything similar and am lost.

mpetry912 

I think the OP is very lucky he was not transported backwards or forwards in the space time continuum

or did not set the world on fire

good luck with it

/markp

Doc_Wui

I own one controller that has a learning input, used once during the initial connection to a motor. It analyzes the motor and sensor circuits, and then sets the timing when the inputs are connected. Then the connection is opened, and the circuit is never actuated again, Most of my other controllers are KT controllers, which don't have learning inputs, However, some of the unofficial schematics I have seen for KT controllers show a motor controller chip that has learning circuit inputs, which are disabled.

In either case, that suggests there is a motor sequence stored in onboard memory in a motor controller chip that
may be corrupted. I've read reports about controllers sold with the direct drive hubmotors suddenly reversing after long usage,