Esk8 calculator

@b264 this one I posted before is in an open format (.xlsx)… were you still planning on making it into an online racing calculator?

^the information given by the calculator is the max possible velocity up slope in miles per hour and the gear ratio necessary to achieve that up slope velocity on the right side.

input is the 13 values on the top left including slope %, vehicle mass, G, frontal area m^2, wind drag coefficient, fluid density of air, motor quantity, motor kv, motor resistance ohms, battery current limit amps per motor, battery voltage, tire diamter in mm & max controller duty cycle %

losses factored are wind, slope, copper loss and max duty cycle (which affects the max effective battery voltage to the motor). motor saturation, rolling resistance, iron, controller and battery losses are ignored.

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xlsx is fine, but the other one you posted was some vendorlocked apple crap

Yes, but the onus of fixing the apple problems is always on the apple users, not on me.

the other calculator is basically 36 instances of the same calculator with the results charted for 6 different battery amp limit settings (10a, 20a, 30a, 40a, 50a, 60a) and 6 different grades per battery amp limit setting (0%, 5%, 10%, 15%, 20%, 25%)

@3_2016 There is no standard, everyone is different. If you haven’t measured your own yet, then use the default 11.2Wh/km

Gotcha, thanks for the info and the calculator!

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Hey @b264 . Do you know of an old fashioned easy way to figure out my wh? I burnt my bluetooth in the fire so I dont think I have an electronic to tell me this easily.

If you mean Wh, what battery do you have? What cells and configuration?

12s6p 30q
7"innova
15/44
Dual 6354 190kv flipsky
If my memory is correct I have limits set at 80/80/40/10 (might be completely wrong but going to bed and dont wanna have to turn on the computer)

10.8Wh times 72 cells is 777.6Wh total but it’s rare that you’d completely discharge a pack and as time progresses (cycle count goes up) then the capacity goes down a bit.

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Where does the 10.8 come from?

Wh capacity of each cell 7+ Wh is typical
3.6V nominal x 3Ah (Samsung 30Q) = 10.8 Wh

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What about the wh/km?

i think you could calculate that with this

Just spotted a little bug in the battery summary:
image

The voltage shown is independent of the cell type voltage and it seems to always assumes 4.2V/cell.

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It assumes a fully charged battery.

I may be wrong. @b264

Try this, it’s what I use.

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I have a few questions about what data im logging in.

would this be the right thread to ask in?

Ask away

awseome

When it ask what AH the cell is would it be the mah? for instance a 40t is rated at 4000mah so would it be 4 AH?

Also how goes one know how many poles there motor is? Is there a standard?

And one more quick one, what efficiency % would you say to use when running 8" tires?

Thank you man, I’ve been guessing and playing around and my numbers seems about right but id like to get an experts advise.

AH is amp henries and we don’t use those.

Ah is amp hours and it’s one thousand mAh

mah is milli atto hours and we don’t use those

MAH is mega amp henries and we don’t use those

mAh is milli amp hours and is typically the units manufacturers use to rate cells. 1000mAh = 1Ah

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