KT 1500W controller + Motor halt when accelerating

Dear e-bike mates,
I finished my e-bike build with chinese KT 1500W controller and motor kit with LCD3. This kit:https://www.aliexpress.com/item/329...earchweb0_0,searchweb201602_,searchweb201603_

It is nice, but i have a problem with it.
It sometimes halt for a moment when accelerating. It is not related with the power draw nor the pas/throttle mode.
It do this even in pas level 1, or i hardly accelerating, but never do again in steady speed or full throttle, only when accelerating from low speed. And it is acting like braking, holding back the bicycle, not just like release the throttle and freely rolling.
I have no brake sensor connected and the regen brakeing is disabled in parameter menu.
I have a bluetooth BMS and power analyzer so i checked that it is not a battery releated issue and it is not, battery is good.
I checked the connections and the Hall sensors with multimeter too in the motor, and it is all good.
I do not know what will be the problem, maybe the controller itself?
Do you have such symptoms?
Thank you for your help!

bojlihal said:

It is not related with the power draw nor the pas/throttle mode.

Click to expand...

How did you arrive at this conclusion?
I know for my KT controller, it effectively works like it’s in speed throttle rather than torque throttle mode, when in the throttle voltage range, and then will cut power and coast when fully released (0V). A speed mode throttle will feel like braking whenever the throttle position is lower than the RPM for that position, and slow the motor to that speed.


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E-HP said:

bojlihal said:

It is not related with the power draw nor the pas/throttle mode.

Click to expand...

How did you arrive at this conclusion?
I know for my KT controller, it effectively works like it’s in speed throttle rather than torque throttle mode, when in the throttle voltage range, and then will cut power and coast when fully released (0V). A speed mode throttle will feel like braking whenever the throttle position is lower than the RPM for that position, and slow the motor to that speed.


Sent from my iPhone using Tapatalk

Click to expand...

I mean not releated for only one mode, or condition.
It makes in PAS mode or when only use the throttle too and makes at low wattage 2-300W and near 1500W too.
But what i noticed higher the wattage higher the halt/brake felling.

Can't help much regarding what's halting/interrupting your power, but I can share that a direct drive rear hub WILL have a slight braking action when the power to it is cut - even without the regen feature.

I made further investigation.
I made three led hall tester with external battery and connected to the motor.
As i rotate the wheel it nicely lit and follow the 120° motor hall sequence, tried slow and fast and never skiped any led.
Disconnected the throtte cable from the controller and tried using only PAS, it skipping.
Tried disconnected the pas cable and use only the throttle, it skipping.
Disconnected the hall sensor cable and used in sensorless mode, never did the skip.
Now the question is where is the faulty?
The controller itself or if there is a load sometimes one hall is skip and the controller tries switching to sensorless mode and that is causing the one moment halt.