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Discussion Starter #1 (Edited)
I thought I posted this yesterday but I don't see it anywhere. I also realize this seems to be mostly a EV car/bike forum but the tech is pretty much the same (or is it?)

Attempting to upgrade to 72V Kelly KPM motor controllers but using my current throttles from a 48V system.

The throttles are/were custom from a company no longer available hence no wiring diagram. These do not appear to be normal pots as they have a circuit board in the housing rather than the standard wiper.

I took voltage measurements of the throttle 6 wires with a multimeter while they were hooked up to the 48v system. I've attached an image with my findings for one of the throttle controls. It looks like I have a throttle signal wire / forward and reverse but not sure about the wires with 12v,9v and 2.5v

I spoke to Kelly Controls regarding a bi-directional setting called "joystick" and they have been pretty helpful until I got this answer which I have no idea what she means regarding the throttle starting at 2.5V?

"if you use joystick setting,you must set the throttle signal at 2.5V before power is on.
Otherwise it will report 2-4 code.Did you start the throttle from 2.5V position when you use joystick?"


I'm a hobbyist and not an electronics engineer so any help would be appreciated in helping me understand what I am looking at.


Thank you!
 

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I spoke to Kelly Controls regarding a bi-directional setting called "joystick" and they have been pretty helpful until I got this answer which I have no idea what she means regarding the throttle starting at 2.5V?

"if you use joystick setting,you must set the throttle signal at 2.5V before power is on.
Otherwise it will report 2-4 code.Did you start the throttle from 2.5V position when you use joystick?"
I think that they're saying that this is a zero to 5V input, so if you use it for forward at one end of the lever travel and reverse at the other, then neutral is in the middle at 2.5 V... and you need to set the control at neutral before the controller is powered on to avoid an error when in joystick mode.
 

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I think that they're saying that this is a zero to 5V input, so if you use it for forward at one end of the lever travel and reverse at the other, then neutral is in the middle at 2.5 V... and you need to set the control at neutral before the controller is powered on to avoid an error when in joystick mode.
That's how I understood it as well but this is where I'm a bit lost, when you say set the control at neutral are you meaning the throttles?

These throttles have a neutral that has a subtle 'click' pretty much when they are vertical. Then there is a dead zone until you 'click' into forward and same for reverse.
If neutral is currently 0v and full forward / reverse are both +/- 5V then should I be starting the controller while throttle is half way (2.5v) in either direction?
 

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That's how I understood it as well but this is where I'm a bit lost, when you say set the control at neutral are you meaning the throttles?
Yes. It makes sense that the controller would be programmed to avoid starting up at anything other than zero power, just as a modern car with an automatic transmission is designed so that you can't shift it into Drive or Reverse unless you have your foot on the brake pedal, so it won't jump when you shift it.

These throttles have a neutral that has a subtle 'click' pretty much when they are vertical. Then there is a dead zone until you 'click' into forward and same for reverse.
If neutral is currently 0v and full forward / reverse are both +/- 5V then should I be starting the controller while throttle is half way (2.5v) in either direction?
Ah... now it makes more sense. :)
I don't think Kelly is expecting throttle controls like yours. I think they expect the same input as a typical accelerator pedal sensor, running from zero to 5 V in one direction only. Their joystick mode would allow halfway along the lever travel of this type of throttle lever to be defined as neutral.

Looking at your table again, it seems that your throttles are designed to put out a 0-5V signal for forward on one wire, and another 0-5V signal for reverse on a separate wire. But doesn't the Kelly controller have only one throttle input for 0-5V, plus a separate switch input to select forward and reverse? If that's how the Kelly is set up, rather than using their joystick mode I assume that you would need to feed both throttle outputs to the same input of the controller, using a relay to switch between them... and you would need some way to detect whether the throttle is in forward or reverse both to control the relay and to signal the direction to the controller.

It seems like you have a nice throttle setup that just isn't suitable for the Kelly controller inputs, but I could have missed something.
 
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