Qs moto hub 72360 fardriver power and throttle issue

[Loulou702]

Wired up a new throttle on my keyu f3 th old one still worked but when the new one went on it didn't work tried to put the old one back and now that doesn't either reason I changed throttles was because my qs hub drive would go slightly upon throttle but when applying higher throttle no movement help needed

 

[dominik h]

Have you done the auto learn when you changed the throttle?

 

[Loulou702]

Yes app says everything is good but there is no wheel jutter or even whining sound and the graph shows no sign of voltage change

 

[dominik h]

During the Auto learn the wheel should spin a few seconds.
In the Auto learn process the lower and upper voltage from the throttle should be set to new values

 

[Loulou702]

The wheel doesn't spin when I auto learn I m gunna try to solder the connections

 

[dominik h]

If I do auto learn, the wheel does spin up to the max rpm and it also spins reverse.
I would have a closer look in the manual how to do the auto learn process.

What throttle values do you actually see in the graph menu?

 

[999zip999]

If the auto-learn spins the wheel backwards be careful as it might rotate the chain backwards and the pedal arm and the pedal may hit you. If it's been backwards

 

[Loulou702]

So I checked my throttle and it had a back sensor replaced it but when I throttled it after changing the hall sensors it said lowside mofset error so now I'm stuck depotting my controller

 

[dominik h]

Have you connected the motor?
If you have not vonnected the motor you will get a mosfet error.

 

[Loulou702]

Yes when connected it showed that autolearn was ready until I pulled the throttle then it said loweside mofset after a slight bump from the motor

 

[dominik h]

Was your motor and controller combo running before you started to change things?

 

[Loulou702]

I hadn't got the spacer for the wire on the hub motor so it ate the wires so I changed hall with the wires that was working until my throttle smoked up thus the problems arised

 

[dominik h]

So you can only double check if everything is ok, and probably the controller was damaged.

The fardriver detects and survives short circuits on the phase wires. I had mine melted and shorted.
But I do not know if it survises a short circuit between hall and phase wires

 

[Loulou702]

Any tips on de potting a controller? Couldn't find anything on that and maybe controller schematics

 

[dominik h]

Sorry can't help you with depotting.
The Sabvoton SVMC72260 i changed all the fets was not potted.
After the fets were changed. It worked again for a few days, and then it didn't recognize the halls anymore.
And as i am no electronic expert that was the end with this controller. A lot of work and money was wasted trying to repair it, and i was shure that it is a controller problem, because it worked with another Sabvoton without any changes , and without any problems.

The now used ND72680 was only twice the price of the changed Mosfets.

 

[amberwolf]

Since your motor cable was damaged, it probably shorted multiple things together inside it, such as phase wires and hall signals. This damages FETS and often their gate drivers, and sometimes can even damage the control lines from the MCU to the gate drivers.

It can also damage the MCU itself so that it can't read the hall signals from the motor. If the controller doesn't have a sensorless mode then the controller is useless when that happens (you can't buy a new pre-programmed MCU for these things if either of these problems happens).

There's virtually no schematic or other information on specific controller designs, so you'll need to do all the reverse engineering yourself during the troubleshooting process. There are threads around here you can search for that may have some applicable info to get you started, where others have tried to repair or modify their similar controllers.

If you haven't already replaced the cable from the motor to the controller, I'd recommend doing that first to ensure there's no damaged wiring between them, before you replace the controller.

 

[Loulou702]

Okay now I've got done doing the mosfets but now when I throttle it goes backwards and forwards and has a weak throttle response

 

[dominik h]

Does the motor make a full turn, or does it move only a few degrees back and forward?
Or does it turn backwards after regenerating with the wheel lifted from the ground?

 

[Loulou702]

Lifted off of the ground it would bump forward once or twice and then in the same direction make a quarter turn after releasing the throttle and applying it again it then does the same motion

 

[dominik h]

The quarter turn back is coming from the regen, zwischen does not happen on the road.
Have you checked the voltage reading from the throotle in the graph from the controllet?