Accelerator Range

[AdvancedEVguy]

I am having an issue with the way my accelerator pedal works. I am thinking it is likely to have a short in the potentiometer. Wondering if anyone can give me any suggestions here. When I press the pedal to the floor and let the cart get up to max speed, then slowly back it off, it does not slow down at all until I reach the last 20-30% of the pedal's travel. This makes it very difficult to regulate speed. About all I can do now is treat it like a toggle switch to maintain a lower speed. Painful. I will soon have programming capability, so if anyone can point me in the right direction, that would be awesome. Once I am able to troubleshoot it and identify the cause, I am certain I can get the dealer to cough up a replacement part. Right now I am at their mercy.

[ATrain]

When you get the cable/software going, I think you may be able to monitor the pot voltage in the software so you can test your theory.

My cart also behaves similarly to how you describe for a data point.

There also may be different tiered setting where you can adjust the acceleration curve. It's like A, B, C, D, E where you set 0-25, 26-50, etc to make your acceleration curve.

[AdvancedEVguy]

It makes sense if you think about how a pot works. With 5 volts on one end and ground at the other (typical configuration for this type of control scheme, I am making an assumption based on experience), if you have a short, the 5 volts is applied closer to ground on the element. The 5 volt to ground change is only in a small section of the device, so your active travel is limited, the rest is dead space. I've seen this numerous times in my career. Hard to convince someone who doesn't understand how this stuff works. They press the pedal, it goes. Teh release the pedal it stops, so it works.

[AdvancedEVguy]

OK, so here is what I have found. I ran the software in monitor mode with the cart's switch in neutral and ran the accelerator pedal up and down. The voltage starts at .1V and begins to increase shortly after the movement begins toward the floor. The accelerator switch activates at about 25% of pedal travel and the voltage reads 2.7. Continuing to the floor, the voltage tops out at 4.7V, but this occurs at about 60% of pedal travel. I am wondering if there is a linkage adjustment that affects this relationship? Upon releasing the pedal, the accel switch turns off at 2.2VDC. I am not sure what all this means, but this is what I have bene able to learn. I do believe the most likely scenario is a short in the accel pot.

[ATrain]

Originally Posted by AdvancedEVguy

OK, so here is what I have found. I ran the software in monitor mode with the cart's switch in neutral and ran the accelerator pedal up and down. The voltage starts at .1V and begins to increase shortly after the movement begins toward the floor. The accelerator switch activates at about 25% of pedal travel and the voltage reads 2.7. Continuing to the floor, the voltage tops out at 4.7V, but this occurs at about 60% of pedal travel. I am wondering if there is a linkage adjustment that affects this relationship? Upon releasing the pedal, the accel switch turns off at 2.2VDC. I am not sure what all this means, but this is what I have bene able to learn. I do believe the most likely scenario is a short in the accel pot.

In the programming software, look at lines 6-9. You might tweak those.

Also, look at lines 138 + 139-143 and those might have an effect.

I don't have my garage or programming cable for a few months so I can't check/screenshot, but somewhere in the tuning section, I think there is a (+) symbol or something that lets you expand the graphs. In one of those graphs I think there's an acceleration curve that changes are you adjust certain parameters.

I think factory is something like this:

139: 1103-1881 RPM
140: 1881-3136 RPM
141: 3136-3763 RPM
142: 3763-4516 RPM
143: 4516 - 9999 RPM

If you mess with those, you might get some changes too.

[AdvancedEVguy]

Lines 139-143 have very strange values in my controller. I'll post that later. Not sure what they mean, but I am guessing they are doing nothing at this point.

As far as the accelerator pedal, if you look at the wiring diagram you posted, the accelerator circuit consists of a pot with one end to ground, the other end to +5VDC and the wiper to an input on the controller. The only way it can reach its full value (4.7VDC in this case) before the pedal reaches its full travel is if there is a short or a mechanical feature which drives the pot to its full travel before the pedal. The other issue (there is another unanswered thread for this) is that the accel switch does not activate until the pedal has been depressed a couple of inches, where the voltage has already reached 2.7, making low speed operation impossible. The accel range is already at 60% by the time the switch engages.

[AdvancedEVguy]

Here is a screen shot of my Torque Limits. Not sure why it is programmed this way, unless the dealer did it, not really understanding what they were doing. Since the values are in RPM, the E point is probably the only one that is active, since it is 35. It doesn't take long fore the motor to reach 35 RPM. I am guessing they thought it was in MPH. Even the max values don't make a lot of sense. I am going to try this with #138 set to zero, to disable the torque limits and see what that does to the performance. I attached the document as a pdf, since I can't seem to get it to embed in the message.

[AdvancedEVguy]

Does anyone understand the Auto Matching section? I just noticed that on my machine, Max Drive_Torque (#149) is set to 59, the same value as NT Limit Torque A (#144). I doubt this is a coincidence. I am guessing this value limits the torque, even if the torque limit flag is set to false (0). I am also guessing that any value above this in the torque limit table is ignored when the flag is set to true (1).

[ATrain]

Originally Posted by AdvancedEVguy

Lines 139-143 have very strange values in my controller. I'll post that later. Not sure what they mean, but I am guessing they are doing nothing at this point.

As far as the accelerator pedal, if you look at the wiring diagram you posted, the accelerator circuit consists of a pot with one end to ground, the other end to +5VDC and the wiper to an input on the controller. The only way it can reach its full value (4.7VDC in this case) before the pedal reaches its full travel is if there is a short or a mechanical feature which drives the pot to its full travel before the pedal. The other issue (there is another unanswered thread for this) is that the accel switch does not activate until the pedal has been depressed a couple of inches, where the voltage has already reached 2.7, making low speed operation impossible. The accel range is already at 60% by the time the switch engages.

Here are my settings, but look at the unit (RPM). Yours don't make a ton of sense. Mine are a bit odd too.


Look where I highlight to click on the left side of the image and click it. That's what those points are for, to make the acceleration curve I think.

I think those might tell the controller how much power to send to the motor based on the pot readings? So if you mess with those, you may get different responses?

Your max values of 100 are unusual. You should find the ConfigurationInformationFile.xml file in your ICON install directory and open it in a text editor and search for "Speed Point A" and see what the units and things are.

There are multiple releases of the software where they changed these files. In one of the installs I just looked at it has different unit than my screenshot.


This is a murky area...

[Carryone]

Hi
think you have changed some other setting
Unit says rpm but your shows Km/h
Limit Speed Point E 35 km/h

what do you have on Motor Speed Unit ? 0 or 1