EV48-400-C Tuning

[evoster]

Originally Posted by PGJ

I didn't touch the torque factor settings. Would like to know more about this and what it does before messing with it.

Look at post #1 of this thread, I give an in-depth description of torque and why YOU DO want to adjust for various profiles.
https://www.buggiesgonewild.com/show...18&postcount=1

I give more words on torque here in this FJ post. The 400-C uses 7 Electromotion Torque Factor settings which have same purpose as the 7 FJ Torque Partitions
https://www.buggiesgonewild.com/show...00&postcount=2

[PGJ]

Originally Posted by evoster

Look at post #1 of this thread, I give an in-depth description of torque and why YOU DO want to adjust for various profiles.
https://www.buggiesgonewild.com/show...18&postcount=1

I give more words on torque here in this FJ post. The 400-C uses 7 Electromotion Torque Factor settings which have same purpose as the 7 FJ Torque Partitions
https://www.buggiesgonewild.com/show...00&postcount=2

Why are they set so low in stock configuration? Am leery about bumping them up to 95-100.

[evoster]

Originally Posted by PGJ

Why are they set so low in stock configuration? Am leery about bumping them up to 95-100.

Tuning is not a one size fits all. Use numbers that you are comfortable and safe with.

Don't make large changes all at once. Add/subtract small amounts towards your target, test, rinse/repeat.

[PGJ]

Things I learned today:
1. The speedo was off quite a bit. Did a 5-mile test run with a GPS and the cart said 5 miles, but the GPS only said 4.72. Noticed that it was about 1.5-2mph off the whole time as well (said I was going 28, but in reality only 26). Adjusted the tire diameter setting from 580 to 560mm and it's pretty much right on the button now.

2.Now, my cart tops out at 26mph (even though the RPMs have been adjusted to 6000). Went into the app under the "accelerator" tab and changed the "maximum voltage of accelerator" from 4.2V to 4.4. Figured more power more speed. That dropped my speed from 26 to 25. Weird. Went in and changed it to 3.9 and now it tops out around 28-29. Could probably drop it a little more and get more speed....but it's plenty fast now. Just thought it was weird that dropping it from 4.2 to 3.9 would make it go faster.

[evoster]

Originally Posted by PGJ

changed the "maximum voltage of accelerator" from 4.2V to 4.4. Figured more power more speed. That dropped my speed from 26 to 25. Weird. Went in and changed it to 3.9 and now it tops out around 28-29. Could probably drop it a little more and get more speed....but it's plenty fast now. Just thought it was weird that dropping it from 4.2 to 3.9 would make it go faster.

Changing that didn't change the voltage coming out of the accelerator potentiometer, it changed the scale used by the controller to determine pedal position and therefore target RPM.

Instead of a max pedal depression at 4.2v, the controller was looking for a max reading of 4.4v.

Changing the setting to 3.9v will NOT give you more speed, it will instead max your rpm before full pedal travel.

To read what your actual pedal ranges are so you can set correctly, measure at the connector. Check out attached picture for pinout.

TLDR:

The accelerator potentiometer is a variable resistor that outputs a voltage signal between a low and high reference. In your system:

Potentiometer Low Reference (Pin 6) = ~0.5 V (default)
Potentiometer High Reference (Pin 5) = ~4.2 V (default)

This means:
0.5 V corresponds to no throttle (0% input)
4.2 V corresponds to full throttle (100% input)

Your controller's RPM range is from 0 to 6000 RPM. The accelerator pot acts as an analog input that proportionally commands motor speed. Based on default settings:

Pot Voltage -- Throttle % ---Target RPM
0.5 V ----------- 0%------------ 0 RPM
2.35 V --------- 50% ---------- 3000 RPM
4.2 V ---------- 100% --------- 6000 RPM

If your potentiometer only outputs a maximum of 4.2 V, but you set the software high detection threshold to 4.5 V:

You Lose Full Throttle Range
The software expects 4.5 V to mean 100% throttle (6000 RPM), but your pot can only go up to 4.2 V. So:

At 4.2 V (your real full pedal press), the software sees:
(4.2 V - 0.5 V) / (4.5 V - 0.5 V) = 3.7 / 4.0 = 92.5% throttle

So, you will only reach 92.5% of the full RPM, i.e.,
6000 × 0.925 = 5550 RPM max

Your pedal feels underpowered near the top.
You never reach full motor performance, even at full pedal travel.

If your pot outputs up to 4.2 V, but you set the software high threshold to 3.9 V:

Full Throttle Is Reached Early (Before Full Pedal)
The software thinks 3.9 V is full throttle.

But your pot continues increasing up to 4.2 V.

So 100% throttle is already hit at 3.9 V, and anything above is ignored or clipped.

Throttle feels more sensitive — full RPM is reached with less pedal travel.
Pedal has less resolution, especially near the end of the stroke.
Makes fine control harder, especially at low speeds or maneuvering.

Best practice is to match the software to the actual pot output range for accurate control.

[PGJ]

Originally Posted by evoster

Changing that didn't change the voltage coming out of the accelerator potentiometer, it changed the scale used by the controller to determine pedal position and therefore target RPM.

Instead of a max pedal depression at 4.2v, the controller was looking for a max reading of 4.4v.

Changing the setting to 3.9v will NOT give you more speed, it will instead max your rpm before full pedal travel.

To read what your actual pedal ranges are so you can set correctly, measure at the connector. Check out attached picture for pinout.

TLDR:

The accelerator potentiometer is a variable resistor that outputs a voltage signal between a low and high reference. In your system:

Potentiometer Low Reference (Pin 6) = ~0.5 V (default)
Potentiometer High Reference (Pin 5) = ~4.2 V (default)

This means:
0.5 V corresponds to no throttle (0% input)
4.2 V corresponds to full throttle (100% input)

Your controller's RPM range is from 0 to 6000 RPM. The accelerator pot acts as an analog input that proportionally commands motor speed. Based on default settings:

Pot Voltage -- Throttle % ---Target RPM
0.5 V ----------- 0%------------ 0 RPM
2.35 V --------- 50% ---------- 3000 RPM
4.2 V ---------- 100% --------- 6000 RPM

If your potentiometer only outputs a maximum of 4.2 V, but you set the software high detection threshold to 4.5 V:

You Lose Full Throttle Range
The software expects 4.5 V to mean 100% throttle (6000 RPM), but your pot can only go up to 4.2 V. So:

At 4.2 V (your real full pedal press), the software sees:
(4.2 V - 0.5 V) / (4.5 V - 0.5 V) = 3.7 / 4.0 = 92.5% throttle

So, you will only reach 92.5% of the full RPM, i.e.,
6000 × 0.925 = 5550 RPM max

Your pedal feels underpowered near the top.
You never reach full motor performance, even at full pedal travel.

If your pot outputs up to 4.2 V, but you set the software high threshold to 3.9 V:

Full Throttle Is Reached Early (Before Full Pedal)
The software thinks 3.9 V is full throttle.

But your pot continues increasing up to 4.2 V.

So 100% throttle is already hit at 3.9 V, and anything above is ignored or clipped.

Throttle feels more sensitive — full RPM is reached with less pedal travel.
Pedal has less resolution, especially near the end of the stroke.
Makes fine control harder, especially at low speeds or maneuvering.

Best practice is to match the software to the actual pot output range for accurate control.

This is all over my head, but the GPS says it's going 29mpg at 3.9V and would only hit 26 at 4.2, and 25 at 4.4V. I don't know why, but that's what it does.