Shorting out problem?

Hi,

I'm having this same problem except much worse.

I'm having some problems with my EVD-Lithium. My controller seems not to be firing on all phases. When the power's off, the rear wheel runs smooth. Power on, it runs very jerky and rough, with low speed.

It could be a bad connection, but it may also be a damaged controller. RMartin said they have one left, but are not sure which EVD it's made for - Lead Acid or Lithium. Is there a difference?

Questions:
-What tests can I perform to determine the exact cause of the problem?
-How do I get the controller off? Unwrap the cable bundle, then... there are a few small leads as well.
-Are the Lithium and EVD controllers compatible?
-What kind of tech could repair this controller? What yellow pages category would have the expertise that could fix it? Industrial tech? Golf cart dealers?
-Is there an adequate replacement for the 6-phase controller used by RMartin / eFun? I read a thread where TimWms was experimenting with possible Kelly controllers.

Any help from anyone would be appreciated. The bike is essentially dead with this problem. Not safe to ride, slow, and rough.

If that is a non-brushed motor your problem sounds very much like one I had with a defective Hall-switch in the motor. The motor behaved like an ICE with irregular combustion only on one of four cyclinders, and the sounds and sensations where very similar, too :-) No more than walking pace was possible, and a very jerky one at that. Some motors thus have two sets of hall sensor mounted. Usually there is lead and connector with 5 phases (+ and - Voltage, 3 sensor out), and if there is a second one hanging around unplugged nearby, it might fix your problem to unplug the connected plug and connect the other plug with the controller.

If not it could get messy, as the motor needs to be taken apart in order to get to the hall sensors and replace them.

If one hall swtich conks out the effect would be that one out of three commutations the controller gets no signal and thus does not power up the corresponding motor phase, possibly accompanied by irregular fault detection and shut-off cycles from the controller.

It is also possible to test if all three halls sensors are actually working, by first finding out which of the 5 leads are the + and - of the usually 5V supply, and then testing the reaction of the other three leads to the - (or the +) lead, while turing the motor by hand with ignition on. The voltage should regulalry switch on and off at the sensor out lead. If one of the three shows not reaction to turning the motor it is the faulty one. If all three work, then it might have something to do with the motor phases and how the controller powers them...