KU123 Controller

Lessss

1 MW
Joined
Nov 18, 2006
Messages
2,345
Location
Saint John N.B. Canada, Sol 3
I finally took the time to get my winter trike ready and plugged in a new KU123 controller. I wire it up and it oddly goes goes full throttle immediately even though the throttle isn't even plugged in yet. !?!? Ok I must be going senile.

Two red wires connected for 36V instead of 48? Check but they are now green wires.
Shorted the LED810 red and blue to turn on the controller? Check
Double blue for cruise disconnected? Check
Speed limiter white wires disconnected for unlimited? Check
3 speed blue black green not connected? Check
brake cutoffs not connected yet? Check
Throttle not connected yet? Check
Pedal assist RGB not connected? Check

Ok I don't get it? Am I missing something from senility or has the wiring diagram changed?
 
Ok the sticker on the controller says connect the two Red wires for 36V 48V select. There are no red wires. All the other wires are explained on the wiring diagram pdf except a lone blue wire and two small green wires which I had assumed were the 36/48 select.

I undo the two green and the motor operates properly now but what the hell is the 36/48V select?
I suspect the wire identified in the diagram as cruise control is actually the 36/48V select.
 
BMsbattery says the ku123 is automatic detection of 36/48V

The cruise control is still the cruse control
The lone blue connector is a high voltage brake?

New problem.
I can operate the bike but only at low throttle(like barely on). It will climb hills etc.. but If I go full throttle it operates for about 5 seconds makes a squeak and shuts off and I have to turn it off and on again to start going again. I think it is the Low voltage cut off. I think the controller is in 48V mode operating with a 36V battery and it voltage sags under full throttle and shuts down.

OK so how to force the controller into 36V mode???
 
Early KU123 controllers had a two though holes labelled XZ, you added a link to alter the low volt cutoff to run on 36V or 48V. Are you sure they are auto detect?
 
BMS went on a 4 day business trip. Waiting on them to come back
I opened a controller looking for XZ on the controller and couldn't find one.

I thought it might be a bms cut out on the battery so went to another 36V batt and same behaviour.

I tried the controller with a 48V battery and same behaviour. Works at low throttle but go full throttle and you get about 5 seconds it makes a squeal and dies.

I removed the KU123 and put on a controller from another retailer and bike is working fine but now I have 2 dud Ku123's. IMO these were put together wrong, someone at the factory probably did a whole weeks worth wrong or something. We'll have to see what BMS says after their "trip".
 
They were about to send me 4 new controllers if I paid shipping. I replied send one, Tested and all connections properly labelled. If it works I'll open it and compare the wiring connections on the others and see if the other 4 are miss-wired. If it doesn't work then I know that these new Ku123's a to be avoided. Waiting on it's arrival.
 
Ok the one replacement arrived. They still didn't label the mystery connections.
I wired up what was labelled (exactly the same as the other controllers) and it works properly.

I opened one of the 4 bad ones and the new one and they are all the same revision number b12_v1.2 20130108. There are wiring differences but only on the common black ground wires. It's all a common negative return so that doesn't matter. All other wires are the same.

So they are not wired wrong. I did not wire them up incorrectly (other than the erroneous sticker that says to connect two non-existent red wires for 36V mode).

It appears I was sent 4 duds.

I did notice however that the PCB boards are too narrow to properly sit in the groove of the heat sink case wall. The boards are able to bend with vibration and contact the case. HPIM2351.JPG
The boards need to be about 3 mm wider to fit properly.

So it could be that the caps or something contacted the case and fried/damaged the board. Rare that this would happen with all 4 boards but possible. More likely is that connecting the 2 green wires(mistaking them for the 2 red the sticker says to connect) puts the controllers into PAS mode and there is no way to get them out of it.

Does anyone know how to "reset" these controllers in case they are stuck in PAS mode?
 
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