6KM Slide mode via pressure switch ( KT36/48SVPR-GLT2F 1 or KTE 6S3-D3C Controller)

[SuperHans]

Hello,

I am currently developing not-for-profit movement aids for children with restricted mobility. I would like to/must use an E_bike motor for this and throttle it to 6km/h in an absolutely binding and non-manipulable way. I am currently using an AKM-75SX and a KT36/48SVPR-GLT2F 1 (name on circuit board: KTE 6S3-D3C) controller (in conjunction with the LCD 5 display).

It works perfectly, but to avoid “manipulation” I would do without the display and accelerate the motor to 6 km/h just by actuating a pressure switch. Allegedly (source ChatGPT) there is an “X5”, “SW”, “6KM” or “Walk” pin on the circuit board of most KT controllers, which only needs to be pulled to ground via a pressure switch! I have of course unscrewed the controller directly, but can only discover an x5 pin already occupied by the white wire coming from the coming wire - neither “SW”, “6KM” or “Walk”.

Unfortunately, I have not been able to find any further information on this AI-generated statement and would therefore like to ask you here whether this (6km/h pin to ground to activate the push mode without display) is actually feasible, the KT36/48SVPR-GLT2F 1 or KTE 6S3-D3C has such a pin (under which designation). If it is not possible with this particular controller, perhaps someone knows an alternative controller with which this functionality is possible : ) ?

I would be very happy about your answers.
Thanks and best regards, Hannes

 

[E-HP]

Not using the walk option if the controller, but perhaps an alternate approach. You could use a potentiometer as a voltage divider to output a throttle signal set for your desired assistance, and a pushbutton switch on the throttle signal wire to activate assistance.
I did this to create a “coasting” button on my ebike before that provided just enough assistance to let my bike “coast” for long periods, or to use when navigating slowly through foot traffic.

 

[SuperHans]

Thanks for the reply! Unfortunately that won't work since the setup needs to be as neat, reliable and legally sound and safe as possible. So working with the pins would be my preferred solution.

 

[docw009]

Pull the datasheet for the microcontroller on your controller board. I doubt you will see a walk input pin. I believe it's a firmware routine in the controller that requires a command from the display to invoke.

This schematic is for the Ku63, a KT controller. Posted on this forum years ago.


The S06, which is the 6 FET KT controller, was reverse engineered for the 3rd party firmware prokect. That schematic was reverse engineered in the attachment.

I guess what you could do is put in a little circuit that generates a 10 second ground signal when pressed. Run that into the down arrow button on the KT display. That will cause it to send a walk mode common to the controller.
.

 

[SuperHans]

Great - many thanks. I'm not really trained in reading schematics and only new to bike controllers, but it seemed to me that there is XS that is labeled Speed Limit. It Is this another Speed Limit?! I'd appreciate if you could have a brief look ?! That would be really great. That 10 sec-ground circuit could be a nice hack. Still I wonder whether it can be achieved with this (or any other controller - please let me know if you know of one ) in a more intended and robust way : ) Thanks again!

 

[E-HP]

I would like to/must use an E_bike motor for this and throttle it to 6km/h in an absolutely binding and non-manipulable way. I am currently using an AKM-75SX and a KT36/48SVPR-GLT2F 1 (name on circuit board: KTE 6S3-D3C) controller (in conjunction with the LCD 5 display).

It works perfectly, but to avoid “manipulation” I would do without the display and accelerate the motor to 6 km/h just by actuating a pressure switch.

The 6km/h button on the KT relies on other information, input with the display, to propel the vehicle at 6km/h. It doesn't magically result in 6km/h, but requires the wheel diameter, motor gear ratios and pole counts to provide that speed. So, even if you can trigger the walk mode by tricking the controller, you probably won't be able to implement a 6km/h walk mode speed without somehow accessing those parameters and setting them permanently as the default when there is no display connected.

 

[docw009]

KT controllers will run with a default throttle and a single PAS level, if booted up w.o a display.

The simplest approach is to apply a sufficient throttle voltage to go slow. Find out what the minimum speed that your controller will support on throttle, and see if that's slow enough,

 

[SuperHans]

Thanks again - that all helped a lot : ) Will go with the voltage divider approach and let you know how it went!

 

[E-HP]

Thanks again - that all helped a lot : ) Will go with the voltage divider approach and let you know how it went!

Once you get it set the way you want, you could probably put the potentiometer inside the controller housing to avoid “manipulation”.

 

[amberwolf]

Once you get it set the way you want, you could probably put the potentiometer inside the controller housing to avoid “manipulation”.

Just be sure to insulate the assembly and secure it down, so it doesn't bounce around and touch other stuff in there and blow up your controller.

 

[neptronix]

You could just program it for a stupidly weak current. Yeah, it will take a damn long time to get up to speed, but it won't be able to go faster than that. Then, 100% throttle = 6% speed

Some controllers allow you to limit the range of the throttle, which would be a way to achieve this too.

 

[SuperHans]

Tested the voltage divider approach and it worked like a charm. Thank you! I just received my voltage divider/potentiometer PCBs from China : ) Simple, but still looking good... Will keep you posted!

 

[SuperHans]

Having done some serious testing I'm somewhat puzzled that if bringing the speed down to 6km/h (set without load) this will not be achieved with load e.g. a rider riding it (max speed then around 3km/h ). I neither can explain that nor do I have any idea how to achieve that the vehicle rides up to 6km/h regardless of the weight of the rider (between 20 - 40 kg). Furthermore I realized that the throttle works more or less as a switch only - no really ramping up the velocity. Control voltage is something between 0 - 2V. Your ideas and explanations are very much appreciated - as always : ) Thanks and best regards, Hannes

 

[docw009]

As pointed out earlier by E-HP, 6km/hour is a software mode that uses the wheel diameter and the internal gearing of the motor to determine the motor rpm needed for 6km/hour.

With a potentiometer, you can put sandbags in your vehicles and determine the voltage necessary to run them with a load at certain speeds. Probably close enough, but if you want something safe and reliable, you probably need to spend the money for more control so you have more precise control on the speeds.