Connect KT controller with USB

Smurf2

100 W
Joined
Jun 25, 2022
Messages
158
Hi. I assembled ebike with rear hub which bought in set.

Now I ordered KT controller and display.

I know that KT is different, and not compitable with many Bafang things, but instead that I change settings in KT display, can I change settings with Bafang usb programmed cable on PC/Android?
This cable have same green jack for connection on many controllers.

 
There's no setup program for KT controllers that I am aware of; it's all in the display.

There *is* open source firmware (see the various threads here on ES, or the github site, etc) that you can replace the original firmware with permanently, that because it's opensource you could modify the code to accept setup from a computer this way (I am not sure that it does so natively, AFAIK it still uses the display for that) after you write the program for the computer to do this (or app for your phone).


Any controller would need the program for it (specific to that controller and firmware version) to be able to do anything via a computer or phone, even if it has a serial port (or usb port, rare but available on certain ones now and then).

There are several serial interface types, of different voltage levels, so not every usb-serial cable will work with every controller, either.
 
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google for the 20+ page manual pdf for your particular ktlcd display for all the configuration parameters and how to set.
 
Thanks. I ordered that Bafang cable, I will cancel the order, if you tell that setup is different.

I found something about here:

I saw tutorials how KT display must configure, but looks easier on PC/Phone to change that. But if can't, I will set on display.
 
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I don't know if that cable is compatible or not. You'd have to find out which serial setup it uses (5v, 3.3v, TTL, RS232, etc), and then find out which one the controller you want to use it on has.

I have several different USB-serial cables around to use for different devices because of this, some with the old style DB9, some with loose wires to connect as needed, some with 3.5mm TRS plugs, etc. I think one of them actually has a jumper solder pad on it for 3.3v or 5v operation, though I've only used it for 5v.
 
I think that cable not work, because different setup.

Don't know which protocol using, but know that is CH340 module.

I see that KT controller missing a lot of settings vs Bafang controller, like, not have settings for each (9) Assist level current/speed (%) separately?

I see that KT have current settings, but think that is current for overall, not for separately assist.
 
The kt manual Chenglish and typos can make life harder than necessary but after you have run through the settings a couple of times it all slots into place. PAS levels can be set to speed or power as well as setting an overall power/amp output limit.

Once configured with the correct motor geometry, input sensors, and pas responses, thats it, set and forget..

A throttle or speed control trigger can give you the oomph needed if you find yourself in an unsuitable pas level of a sudden..
 
I think that cable not work, because different setup.

Don't know which protocol using, but know that is CH340 module.

It's not the protocol that matters for which usb-serial to use, it's the serial interface itself (which voltage range and signal type).

The protocol and data format and data content matters between the program being used to communicate with the controller, and the controller itself. Or a display-controller setup.


I see that KT controller missing a lot of settings vs Bafang controller, like, not have settings for each (9) Assist level current/speed (%) separately?

I see that KT have current settings, but think that is current for overall, not for separately assist.
AFAIK if it's not listed in the manuals for the display/controller pair, then no, it isn't available.

The OSFW might have that available, but I haven't read thru the threads for that in a long time, and dont' recall the details.

As far as "bafang controller", there are quite a lot of different bafang systems, each one having different things available or not.

At least some "bafang" controllers are made by LiShui, and some of those (F version for FOC) have OSFW available as well, *if* it's not a locked controller (some are factory locked out from being written to (flashed)).
 
1700496449618.jpg

pic_10202023215935.jpg

@amberwolf
What is OSFW? Can't find.

@stancecoke
Thanks man. That is cool thing.
But it seems that only Bafang settings have separate setup for each PAS Level, and Kunteng have only shorten one (weeker, general, stronger).

Other words, if you connect bafang controller you will have full extended setup, and if you connect KT, you will have shorten setup only with some P and C combinations, in same aplication.

E.g. If I want throttle in PAS1 to be max 10km/h, PAS2 max 22km/h, PAS3 30km/h, I can't do that on KT.

Shocking price of that unit is 100-140$.
 
E.g. If I want throttle in PAS1 to be max 10km/h, PAS2 max 22km/h, PAS3 30km/h, I can't do that on KT.
But why on earth would you want to do that?? thats already handled by the speed or power limit set for the respective pas levels, twisting the throttle wont accelerate you to the desired speed/power limit any faster once the pas is engaged?? So just dont twist the throttle wide open from a standstill and pedal once your moving then your sorted automatically.

The phrase "cutting your own nose off to spite your face" comes to mind.. limiting the throttle speed within 'pas bandwidths' hampers your ability to twist your wrist to get out of a tricky situation.. very counterproductive imho,
 
But why on earth would you want to do that??
Oh, maybe you are right!
Sorry, I think that I am still in old way of use Bafang PAS, like:
- when turning pedal around, bike will going to the max level of speed, which is set for that Pas level. :)

Now PAS will be different, smarter and not frustrating like before, so It looks like I won't need to do that.
 
Im pretty sure that unless your a bleeding edge competitive e biker needing to make the most of every milliamp of power available, you will find the controller config is a set and forget experience once you have found your golden parameters, as it was this end... And any problems or unexpected side effects can be resolved with the aid of some of the real experts in here, Ive only set up and forgotten my own KT controller upgrade the once ;).

If your manual contains confusing typo's and language errors leaving you confused about a particular setting , just cycle through the options til you hit the sweet spot..
 
Hi, I bought KT controller and KT E-BUS cable.

After testing old throttle not working. PAS working.

I had inverted throttle connectors. I will try use my old half-thrittle, comed with Bafang kit.

I bought two mail connectors without ends, and soldered red to red, white white, black black. Maybe can try switch some wires, like white-black?

(Connectors I bought are orange, and old throttle is yellow).

Setting for throttle I tried in next combinations:
P4-0 C4=2
P4=0 C4=4

P4-1 C4=2
P4=1 C4=4

P4-0 C4=0
P4-1 C4=0

Why not working?
 

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If the pinout on your contacts looks like in my picture, you should solder the black to black, red to white and white to red.

I assume that your E-BUS cable also has a female connector, just like the throttle, so you want to create a new cable with which you can connect the throttle to the E-BUS cable.

bhy.png
 
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I assume that your E-BUS cable also has a female connector, just like the throttle, so you want to create a new cable with which you can connect the throttle to the E-BUS cable.
Yes, my old Bafang cable had all inverted connectors, so I bought new for KT one.

Tnanks. I will try resolder those wires.
 
If the pinout on your contacts looks like in my picture, you should solder the black to black, red to white and white to red.
@B_c Sorry, I checked now. It seems that BUS connector which go in Controller have MALE connector. (click on pictutes to see Labels).

Also, I reaplace red-white wire, and it seems something not good. In that point PAS stop working and Battery Indicator show that is empty. Think that must return wires color to color.

I have multimeter If needed.
 

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I don't know the pinout on your E-Bus cable and on the throttle. You have to detect it yourself, otherwise you might damage something.

Where you bought the E-Bus cable and throttle, they should have a diagram or pinout.

Here is an example of what the pinout on my throttle looks like.

Skärmavbild 2024-01-06 kl. 12.48.57.png
 
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Throttle working!

I found on sellers page this pinout for thumb throttle, that must be like mine, because he sells all same stuff only for Bafang.

But I tried that compare with yours (KT) pinout and figure out by logic, that was not sense ti me.

So I turn off a brain, and just try some other remaining combination, and I made it! White must be soldered together! Is that have sense you?

Now I must figure out brake sensors 🙄.
 

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Throttle working!

I found on sellers page this pinout for thumb throttle, that must be like mine, because he sells all same stuff only for Bafang.

But I tried that compare with yours (KT) pinout and figure out by logic, that was not sense ti me.

So I turn off a brain, and just try some other remaining combination, and I made it! White must be soldered together! Is that have sense you?

Now I must figure out brake sensors 🙄.
If you can find the pinout for your brakes, then that wouldn't be a problem. I see that your throttle has a slightly unusual pinout. All the others I've looked at on Aliexpress have a pinout like my throttle.

dif.png

What do the contacts on your brakes and on the E-bus cable look like?
 
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Thanks.
I have new one (spare) sensors
MS-BK-1R, which are good looking and easy for install.


But not worked on my Bafang. They said me that work only on Middle drive motor, not rear hub. So I bought new sensor with magnets (which using today).

Now I want to try is that MS-BK-1R work on KT.
I see that I have some connection - 'brake icon' show on display and block motor. But when I move steel cable left and right inside, not react.

Seems that maybe must try to replace wires, if that help. Two options:

- Connectors fit. But if want replace wires, I can use (spare) male connector without end(beteeen them), but then need female connector which not have.
That female I can cut from old 1T4 BUS cable (and destroy it) to solve this, or
-when connectors fits, just cut wire on sensor directly (destroy it) and replace it.

Found similar design pinout (not same brand) with regular pinout (white=signal), which we all already knows :) But can be different in my case.


EDIT: Forgot upload the picture. Now you see it.
 

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If your cable is 1T4 for Bafang motors, here is a picture that might help if you haven't seen it already.

bf.png
 
If your cable is 1T4 for Bafang motors, here is a picture that might help if you haven't seen it already.

View attachment 345673
Tnx. I forgot upload picture, now you can see it in post #22.

First old cable was Bafang 1T4.
Now have inverted KT 1T5 cable.

Not sure is better to cut new sensor wire or old BUS cable for connector 🤔🤔
 
Ok. It is a voltage problem.
I checked the description for similar sensor, and it says that working from 12-72 v.

I have noticed that sensor has a red light which all time was turned OFF! So I connected 11v and the red light is ON!!

So what now? Why they make ebike sensors for 12-72 voltage, who use that?
There are 5v same sensors, but they very rare and expensive. Ideas?

Also, my old Bafang sensors (with magnet sticking) working on KT (2 black together, combination), but the magnet moves away because of vibrations, and that is frustrating😩
-15495053901774281055.jpg
20240113_231152.jpg
 
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