Just added an example, hope that makes it crystal clear
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Oooh
Cool, ok. I had it inversed in my head 
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Looks like I got into your head. 
I was referring to this specific post:
Please don’t take it as a broadly general thing. I don’t understand what’s happening, but in this specific instance,
- adding 4 cells (12s4p → 13s4p, 8% more cells) increased range 29%
- adding 17 cells (12s4p → 13s5p, 35% more cells) doubled the range
It’s hard to generalize this, and 12s is already a bit risky so it’s hard to recommend 13s.
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Yeah, changing wheel size doesn’t change the torque value in the calculator, so I guess it’s rotational torque that’s being shown. So yeah, you would first need to divide the torque (Nm) by wheel radius to get the force pushing you forward (N), and then you divide by your mass to get acceleration.
My stats:
Torque: 12Nm
Radius: 42.5cm
Acceleration force: 28.24N
My weight: 80kg
Acceleration: 0.353 m/s^2
Edit:
Actually acceleration force is 282.4N, and acceleration is 3.53 m/s^2
which means I’ve made a mistake somewhere, because that is super low.
Another thing I noticed is that the torque displayed in the calculator doesn’t change when you change your battery cell discharge rate, which is bad. Means the max motor wattage is used, even if your battery cannot drive them at that rate. However, I guess that’s OK, because I’m guessing just from max W and KV alone (+ motor efficiency) it calculates the motor torque per amps, and when starting from zero voltages are low, so you’ll be able to drive enough amps easily.
If what I’m saying is true, then I guess you’ll have good startup acceleration irregardless of what battery you have – what matters is motor wattage (well, torque, but usually correlated) and your drive train ratio. Would love for someone to either confirm this or correct me 
I think you got the wrong wheel radius, well unless you use 850mm wheels
Mine is about 2.75m/s/s with 97mm wheels, 16Nm torque and 60kg mass
Edit: I think the wheel radius also must be used in Metres so mine was 0.097m
Yup! That’s where I messed up. Thank you! Now I get 3.53 m/s^2, which seems correct to me.
Everything needs to be in base units, yes
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Why does it say a 12S8P will have less torque then my current 10S4P?
12S8P - 13.8nm after reduction
10S4P - 16.6nm after reduction
When I increase motor max wattage from 3250, the torque goes up as expected. But right now on 10S4P I’m not even pushing 2880+W at 10S-80A battery max(40A/40A)… Which, with voltage sag under full load and charge down to 36 volts, that’s expected- 36v*40A=1440W *2 = 2880W.
By increasing to 12S8P and pushing 120-160A battery max (60-80/60-80), that would be 43.2v(nominal or full charge under load w/sag)*60A = 2592W *2 = 5184W.
How is 5184W less torque than 2880W, from just going from 10S to 12S?
Would it make more sense to be able to input your intended vesc battery and motor max/min values to calculate this better?
What it seems like though, is that the calculator is taking the motor max wattage and not multiplying it by however many motors you have, instead setting a hard wattage limit regardless of number of motors entered.
Then again, if I enter 9999999999 on the motor power rating, the torque goes up to some craaaaaazy number… Shouldn’t the torque be based off your battery max, with the motor rating * # of motors being the absolute wattage limit, and calculating primarily based off your battery and efficiency, with the motor rating acting as a ceiling?
Yeah, the calculator just assumes the max current your motor can handle is watts divided by voltage of your battery. It is very misleading imo. @Kug3lis, please fix
P.S. Would be nice if motor kV didn’t have to be a multiple of 10. TB direct drive is 75kV, so it would be useful to enter such values.
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What formula do you suggest it should use instead?
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People should just have the option to input their motor’s / ESC’s max current that it can handle.
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Those torque values should matter least as they are best ever condition without anything affecting it. In reality I would be happy if you have at least half of it. So I don’t see a point of changing that. Plus your ESC current limit is nothing in reality as your motor can draw up anything it wants until ESC detect over current and limits it. that’s why I use power rating of the motor as manufacture measures how much it can draw.
In that case, perhaps it would be best if instead of dividing motor’s power by the volts of the battery, you should always divide by 50.4V (because that’s what most of our motors are rated to)? I just think something needs to be done so that people can somewhat accurately compare acceleration of different setups.
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Why always divide by that, when we already know the battery voltage? That seems even less useful than the way it is now.
When riding, I see up to 2880 watts on max settings. This doesn’t take into account motor amps, just battery amps and battery voltage.
My motor amps are double my battery amps (80A motor / 40A battery). If ESC / battery amps don’t matter much compared to motor amps, does that mean I’m realistically seeing (80A+80A)*36v = 5760W and not (40A+40A)*36v = 2880W according to my ESC?
In my time riding and changing settings, it feels to me like increasing battery max has the biggest impact on increasing torque. It seems odd that if I set my motors max watts to 4000 from 2880 that it has such a huge impact on the torque calculation. I might be off base here, but I feel like the limit should be what your battery can output, and if your motor max is the limiting factor, that should be the limit. Basically, not whatever is higher (motor or battery) but whatever is lower should be the limit to max wattage being taken into account for max torque calculation.
Again, if a motor is capable of 180A * 2 motors * battery voltage for max watts for each motor, should torque be super high if your battery can only output a max of 30A total? Just asking the question, not saying I’m right, just confused.
Also, does the calculator take into account voltage drop? It’d be neat to be able to enter expected or observed voltage drop under full load, and have that subtracted from the voltage used in various calculations.
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Say I have a generic esk8 motor and a 6s20p battery. The voltage of the battery is pretty low, but that doesn’t mean the ESC cannot drive the motor at an insane current when starting from stationary position. More current -> more torque -> more acceleration.
@skatardude10 Hopefully this answers your questions as well. If you have dual 80A motors, then the max you can have the ESC push them to is 160A in total. With only 40A coming from the battery, that means you can get that insane torque/acceleration only from standing still to about 1/4th of your max speed, which is the voltage at which the ESC would require more power (power = current * voltage), but that it cannot get because of the battery’s limit.
Basically, two identical boards, but one with a 40A max cont. battery, and one with a 20A max cont. battery, will have the same startup acceleration, but the stronger one will be able to maintain that acceleration for precisely twice as long, until it (acceleration) starts going down due to lack of power.
Currently the calculator shows torque while driving at full speed according to your specs (when motor voltage = battery voltage). I personally don’t care what my torque is like when I’m already traveling at high speed, so I think it’s a bit useless at the moment.
It does; it’s based on the nominal voltage. This was a change from version 1.
You can already edit that.
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What formula do you suggest it should use instead?
Since motor manufacturers usually say “up to 12s”, X many watts of total power, then I’m assuming that at 12s voltage and X watts of power the current through the motors is the hottest they can handle safely for extended use. Therefore, even at lower voltages (because heat is purely dependent on current in the motor, not voltage), I think that most of our motor’s max current could be estimated as
Current = X Watts / 50.4Volts
Of course, there are some exceptions, like TorqueBoards, that list their 6355 motor as handling 80A, despite its stated power being only 2500W. (Maybe through testing they just found that 80A is fine when accelerating for a short while, but not permanently, or something) That’s why ideally I’d like to plug in my ESC’s / motor’s max supported current, and if not, then at least calculate motor current by always dividing by 12s voltage. Current method isn’t very useful imho.
Anything involving magic numbers is an almost definite “no”. At least, I’m not going to code that.
So then you are indirectly suggesting to add a “Motor Max Voltage” box and then calculate based on that? Please elaborate
Formulas = good
Walls of text = bad