Get the reading from ebike Throttle to Motor Controller

[hardmouse]

I have purchased an ebike throttle and thought it work as potentiometer, however it's not. I couldn't get correct reading as same as normal potentiometer. The reason I am asking is I'm modifying a used scooter. The old one has only on and off control and I want to replace the throttle and more powerful motor and use another motor controller which originally has a 10K potentiometer on it. I remove the original potentiometer and connect the throttle from ebay which has same 3 wire. Unfortunately, it's not working as I thought.

Anyone has any idea or similar experience? Thanks for any suggestions.

 

[Jeremy Harris]

The throttle you have is a fairly standard Hall effect sensor one, as used on the majority of ebikes. It will have three throttle wires, plus maybe another one or two wires for the switch, depending on the type. The throttle will use typically a +5V supply, a 0V supply and a voltage output wire. The voltage output will vary from between about 0.8V to 1V for throttle closed to about 3.5 V to 4 V for throttle wide open. Your motor controller needs to be able to accept that voltage range on the throttle input and also supply the correct +5 V supply.

From the sound of it, you may be running something without a motor controller, just an on off switch. If so, then you need to add a controller to suit your motor, between the battery and the motor as you've already worked out.

If your new controller you've got is set up for a potentiometer, then ideally you need to look for a potentiometer type throttle. The only after market one I know of is the Magura twist grip, but they are expensive.

It may be that your controller can be converted to run on a voltage output throttle, but we'd need more detail about it to be sure.

 

[d8veh]

That new throttle that you have has 6 wires. The throttle wires are red +5v, black 0v and white signal volts The other three wires are for the switch and the LEDs

 

[hardmouse]

Thank you Jeremy and d8veh. Yes, I know I am going to use only three wire from throttle. The controller I got is this:

I took off the potentiometer(it says B10K on it) an measure the + - pin, it reads 9V, should I regulated down to 5+?
Am I suppose to connect red wire to regulated +5V and black wire to - Gnd? and white to signal?

 

[Drunkskunk]

That Maxx Tronic unit isn't the thing to use. It won't be directly compatable with that throttle at all. You would need to build a circuit that could translate the ~1-4V output of the Hall throttle into the equivilant output the MT controller is looking for. 0-9 volts.


You are better off using a dedicated motor controller like this : http://www.ebay.com/itm/36V-500W-Brushed-Speed-Controller-E-bike-Motor-Scooter-/230657993750

 

[Jeremy Harris]

I agree, that controller is not at all suitable.

What is the new motor that you have? Knowing that we can advise on the best controller to drive it, and that will work with your throttle. Brushed motor controllers that will work with a standard throttle are very cheap and readily available.

 

[hardmouse]

Ah! I see. Thanks for advice. If the problem is at MT controller then I won't bother to use it. I am using 24V 280W brushed motor to replace the original one from e-scooter. I know how to do now. Thank a lot guys~