Throttle wiring

I bought two KT controllers from Topbikekit at the same time and they arrived in the same box. One of them is the same as any other, but the other has weird throttle wiring, if that's what it is.

 

Normally, the PAS, Throttle and speed 3-pin connectors are all in one bunch. This one is the same, but the throttle connector is a 2-pin blue and black. I tried taking a branch off the red 5v and adding the blue and black to make it look like a throttle, but it doesn't work. I have the bike working on the PAS, but I really wanted a throttle to boost power.

 

Unfortunately, I chose the wrong one of the two controllers and I don't want to swap because it took me ages to solder the motor cable after cutting off all the connectors.

 

I've been racking my brain to try to figure out what that 2-pin connector would be for, but I have no answer. Can anybody figure it out?

This is a recent thread on ES that suggests it’s for brakes, but the thread appears to be non conclusive, so don’t bank on it.

 

You will probably have to open up the controller to be sure and then you can check the throttle wiring at the same time.

 

https://endless-sphere.com/sphere/threads/kt-motor-controller-connecting-brake-and-cruise-to-the-circuit-board.124637/

 

This one is a KT48 KTE-SPV12

 

Edited September 9, 20241 yr by AGS

I was wondering about it being an external speed sensor input, but I have no experience at all of these controllers.

 

If it is a brake cut off lead, as AGS suggests saneagle can test that in a jiffy if he has pas running which he has. Upside down bike - turn cranks - motor running - short lead - motor either cuts off or its doesn't..... If it cuts off then lead is a brake sensor lead.

I was wondering about it being an external speed sensor input, but I have no experience at all of these controllers.

 

If it is a brake cut off lead, as AGS suggests saneagle can test that in a jiffy if he has pas running which he has. Upside down bike - turn cranks - motor running - short lead - motor either cuts off or its doesn't..... If it cuts off then lead is a brake sensor lead.

The speed sensor socket is normally red, white and black. There is one on this controller, and it's the only unused 3-pin connector on the controller. I tried it in case it's for throttle, but no joy. There are a pair of brake connectors elsewhere, so I don't think that's it, though the blue wire has 5v on it and the other is ground, which is similar to a brake one.

 

I'll open both controllers today to see what the differences are.

Could it be for the stupid KT lighting circuit? That’s just a guess.

 

Opening the controller is definitely the answer in this case.

One final point for fun that might help if anybody wants to make their final guess before I open the controllers: the voltage on the blue wire is 5.0v. All the sensors have 4.7v on their red wires.

One final point for fun that might help if anybody wants to make their final guess before I open the controllers: the voltage on the blue wire is 5.0v. All the sensors have 4.7v on their red wires.

Lighting?

Could it be for the stupid KT lighting circuit? That’s just a guess.

 

Opening the controller is definitely the answer in this case.

I think you may be the first with the right answer.

I have an answer to the throttle. I'm kicking myself. This controller has the old big white connector in another group that includes the 3-pin brake and old type two-pin brake. The wires are a bit weird in that group, as they're all looped to each other inside the sleeve. It never occurred to me that one could be the throttle because I haven't seen that large one used for a long time. I probably would have got there straight away if I hadn't looked at the wiring diagram in the actual listing, which shows the more common small black connector with red, blue and black, while as mine are red, green and black, which are also old colours that I haven't seen for a long time.

 

Phew! I thought I was going to have to solder all the motor wires again. I can relax now. Incidentally, the other controller is identical. I bought one from another supplier at the same time and got them mixrd up. The one from that supplier has the normal wiring, like shown in the Topbikekit listings, which is where I bought the other two from.

Edited September 10, 20241 yr by saneagle

I have an answer to the throttle. I'm kicking myself.

 

Welcome to the world of senior moments! Don't let it get you down though, at least with most of us the onset isn't until we reach about seventy.

 

For those deluded enough to think they'd make good politicians, it can be anything over twenty years old.

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