The weirdest Controller-Motor issue and nothing helps

david_007

10 µW
Joined
Sep 28, 2021
Messages
5
Hi, I'm dealing with Ebikes troubleshooting for a long time now, but I got an issue that I've never seen,
and after a lot of searching the net, I still didn't find this issue anywhere and I need your help.

My Motor: Bionx 350W - original after re-work and making him generic motor (without the PCB - only phases and sensors)
My Controller: KT 48V - 9 Mosfets
(My battery works well on many e-bikes so it's not the issue - 48V 16Ah with Samsung 40T cells).
FACTS:
1. This motor runs smoothly with a different generic controller (500W and other 250-350W generic cont. with self-learn function).
2. This controller operates correctly with a different motor (500W and 1500W motors worked well).
3. Throttle operation is sending power to the Motor (see attached link - the display shows the power sent to the motor).
4. KT controller doesn't have a self-learn option.
ISSUE:
When everything is connected and should be working, I get this issue:
[youtube]https://youtu.be/IH6cSq0G3cw[/youtube]
Like the motor is stuck, and if I spin the back wheel by hand, the throttle stops the spin.

I tried EVERY combination possible for phases and sensors wires (every single combination...)
I still can't figure out why can't they work together? (remember that separately they work well)

I even opened another KT controller to find the self-lean on the PCB, but the company said that it doesn't have that function.
Any ideas what should I try next? I must have them working together, Thanks.
 
just a guess but have you tried a different throttle is it wired correct for controller , or on pas :wink:
 
Throttle and PAS are making the same result, even when spinning by hand, the motor suddenly stops..
I also tried with a different throttle, got the same result.
 
I'm gonna say, there is a mismatch on phase wires and halls
It is confused so you are getting two phases fighting each other the minute you apply power...

swap two power phases and see...

my guesstimate!

Darren
 
Why do I say? KT controllers assume, yellow blue green halls and phases are consecutive. The generic with learn, will take any frocked up layout and adjust the circuit. KT can't and won't. I know you say you tried. I still think "halls are lined up yellow/blue/green" and phases are yellow/green/blue or some twist like that... And I can be completely wrong.
 
powrtrip said:
Why do I say? KT controllers assume, yellow blue green halls and phases are consecutive. The generic with learn, will take any frocked up layout and adjust the circuit. KT can't and won't. I know you say you tried. I still think "halls are lined up yellow/blue/green" and phases are yellow/green/blue or some twist like that... And I can be completely wrong.

Hey, any other idea besides replacing the wires? it's not the order of the phases, because every combination ends the same way, with the motor stuck and not turn...
what on a new controller makes the motor respond like this...?? starting to lose hope :(
 
Since it runs using a different controller it sure sounds like a mismatch with hall or phase wires. Have you tried this flowchart? https://endless-sphere.com/forums/download/file.php?id=197293&mode=view
I found it helpful when trying to diagnose a noisy motor. It didn't solve the issue but it eliminated possible causes which is progress.

If you get really desperate (as I did) here's a spreadsheet that lists all 36 possible combinations of hall and phase wires.
View attachment Blank Hall Phase Combos.xls
 
MattZ said:
Since it runs using a different controller it sure sounds like a mismatch with hall or phase wires. Have you tried this flowchart? https://endless-sphere.com/forums/download/file.php?id=197293&mode=view
I found it helpful when trying to diagnose a noisy motor. It didn't solve the issue but it eliminated possible causes which is progress.

If you get really desperate (as I did) here's a spreadsheet that lists all 36 possible combinations of hall and phase wires.
Blank Hall Phase Combos.xls

I wish it was the answer for my situation, tried all.. Need another solution :(
 
david_007 said:
FACTS:
1. This motor runs smoothly with a different generic controller (500W and other 250-350W generic cont. with self-learn function).
2. This controller operates correctly with a different motor (500W and 1500W motors worked well).
MattZ said:
Since it runs using a different controller it sure sounds like a mismatch with hall or phase wires. Have you tried this flowchart? https://endless-sphere.com/forums/download/file.php?id=197293&mode=view
I wish it was the answer for my situation, tried all.. Need another solution :(
Given the facts you state above unless you are using a different connection method or wiring adapters to switch motors and controllers there is nothing else it can be. My advice is to go back to square one and start over. Write down the combinations and the results to be certain you don't overlook one. If you are using adapters, check them very carefully.
 
Here is the other solution, don't run this combination of motor and controller together. It does not work. You have ruled out any other possible issues. It could be something as simple as the connectors on this motor are not working with the connectors on the controller. But if a good motor is wired perfectly to a good controller they work. But it is not perfect is it.
 
Thanks for that zeroem :roll: not very constructive to solving issue though, think mattz suggestion going back square one most likely yield a solution or find something you missed :mrgreen:
 
Greendog said:
Thanks for that zeroem :roll: not very constructive to solving issue though, think mattz suggestion going back square one most likely yield a solution or find something you missed :mrgreen:

Not constructive indeed :D , though I did check the wires.. twice just to be sure.

I will try one more time all 36 combinations.. got nothing to lose.

Thanks for all the helpers, appreciate it. I will share if it worked or not.
 
Fact is that ZeroEm is correct, some motors cannot be run with some controllers. I do have a recollection that the Bionx motors have been mentioned with such issues - although might very well have been a different Bionx motor or controller combination so it's anecdotal in regards to this thread.

One example is that the hall triggering can be offset if the magnet field has a small bump over the revolution around switching time
One example is the matching with sine field motor or square field motor vs a sine or square wave controller.
 
david_007 » I know how you feel, that is when I walk away and give it time and come back with a fresh mind. Some time it's the things we over look but sure it is all correct. Glad you are going to walk thru it again.
If I remember correctly some controllers don't work well with some motors. In another thread a motor was noisy, everyone blamed the controller OP replaced the controller. Nothing much changed. Replaced the motor, still the same. Finally purchased a motor from a different company and issue was resolved. It was bad batch of motors. Sometimes it not what we think.

Good luck
 
larsb said:
Fact is that ZeroEm is correct, some motors cannot be run with some controllers.
oh right :thumb: well thanks I Learnt something today then,
kudos to experience, that's what makes this site great,
something about the ghost in the machine springs to mind to, is funny (funny prob not best word) how some electrical things are set in stone can be taken as standard, others are totally illogical electrical gremlins :mrgreen: have had two cars fix like that recently, well at least it works on one controller, not trying be negative but perhaps your modification may have caused some noise as suggested by Z, em
 
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