Duty value?... what is it and should i change it?

Hi guys, This monitor values are from riding up hill… and didnt had enogh power to make it. even with this values (focbox) Battery max 20 Motor max 45 What is this Duty 40% only… i should change it somehow?.. its safe to change it?.. it will give more power?.. need your opinions… Thanks…

I think in simple words: your throttle. So you cannot Change it like a normal vesc Setting (e.g. max Motor amp).

You can only Change that value by giving or releasing throttle :wink:

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But i was at full throttle… and on my app in vesc show 100% throttle when i press all the way.

Someone correct me if I’m wrong but I believe duty is what percent of your max erpm your motor is currently spinning at. I believe the only thing about it you can adjust is your max duty, which should be 95% or so. Were you full throttle at that point in your image posted? It looks like motor current is being limited to 37 amps for some reason.

It’s not your throttle, although it is related.

You have a brushless DC motor, when you apply a constant maximum DC voltage, it’ll spin at it’s maximum speed. As you can see with metr.at your voltage always stays the same (after a while it drops due to battery voltage drop when it’s being depleted, but that’s only a few volts over a large amount of time).

So if we were to just apply the voltage to the DC motor with a switch, it would snap to it’s max speed (if it was able to draw an unlimited amount of current). Which is not what you want. So how do we control the speed of the motor? Via duty cycle. This means that for example for a duty cycle of 40%, 40% of the time, you apply voltage to the motor and 60% of the time, you don’t. This way, the mean voltage over the motor drops and it’ll spin slower.

The thing is, your motor cannot accelerate to max speed with you on the board in just an instant. It takes time as otherwise the current needs to be very high. You are however controlling the current by remote, that is your throttle. So the vesc will try to speed up the motor with the duty cycle, as long as the current that the motor needs in order to do so, is allowed to flow to it. Either limited by you or simply the vesc’s maximum current.

When you are riding up hill, the motor draws more current as it’s putting in more work to get over that steep hill, if the maximum throttle value is reached and your motor is drawing it’s maximum from the batteries (accoridng to your set limits) it won’t increase in speed.

Edit: So in short, if you want to accelerate on that hill. Your batteries must allow more current to the motor or your motor must allow more current to flow. This is limited by either your batteries, vesc or motor.

I believe currently your battery current is set to 15A. IF THEY CAN supply more current, you could raise this value and you will speed up when going on that hill.In general you wil also have a more powerful board.


But as you can see it didnt get to my max settings… My settings are Batt max 20A Motor max 45A Its didnt go up to this values… why?

I cannot figure that one out either :upside_down_face:

Its must be some vesc setting… cant find what it is…

Can we see your Vesc settings?

Here it is.

Duty cycle is speed dependent…

Duty cycle = motor voltage. Motor voltage and kv= rpm…

So no you cannot change it.

In general I think 20 A is very low. You might want to increase that to 40 A, which should be safe, according to the info in your other thread. But regardless, it’s definitely strange that your max values are not reached. Do you have motor temperature sensors? Something your telemetry doesn’t show is the motor temperature. I don’t know that motor, but is you run a small, single motor uphill, then it’s efficiency is extremely low, and this will heat it up very quickly.

Nop. The motor cold right after the test. I checked it. Again, just dont know why the system Not getting to max settings… it can get to y max settings. Its not high values… cant find why its not getting to 20A or higher motor Amps…

So i dont need to touch the duty cycle?..its not it?..

It is… Your motor amps in that picture are 36.9

No, you don’t need to change duty cycle, that values is good :slight_smile:

No… the max battery is set to 20A Motor max is 45A. Its not getting even 40 on my test.

If your not getting the full motor max. Then your ppm endpoints are setup wrong. Or your remote is in beginner mode with 80% throw

Make sure you calibrate your PPM Min(pull throttle full brake and set the value on the green bar, while real time data is enabled)

Do the same for ppm max,and then center point.

Yes. Done that. The line on the vesc software going all the way min/full :confused: also used the wizard auto settings for that. Same thing…

battery max is too low you need to up it.

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