Yeah, I’ve heard that a safe regen is 1C of your pack. So if you had a 7500mAh pack than it’d be -7.5A
Where do you guys get this information from?
cell datasheets. I use -16A for my 4P Samsung 25R pack since their max rated charge is 4A per cell.
the pack is 17.5 ah so it isnt to far off i dont think?
the board took me about two months of saving and collecting parts and many hours to make. i got on it any it was almost unusable. but now it is just awsome. the sun is out today so im going to go out on it. it is just so much fun.
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wow i’m surprised your vescs survived with 70A motor/batt!
Thats because the shortly boosted him to max speed and then they don’t need much amps anymore. Most people think at max speed you use max amps. For example with a street setup you need around 1000 watts power to do 50 km/h. That is around 28 amps in total for a 10S battery. So only 14 amps on each VESC. If max speed is only 40 then you need only 650 watts which is around 18 amps in total and 9 amps on each VESC. Uphill is another story and the acceleration to that speed as well. But once you reached that speed you don’t need that much power anymore.
What formula do you use to calculate the amount of watts needed for a given speed and acceleration?
Just by testing 250 watts is good for around 25 km/h, If you wnat to know the watts for the speed of 40 km/h you have to calculate 40/25 = 1,6 1,6 * 1,6 = 2,56 (<-exponetial because for double the speed you have 4 times the wind and rolling resistance) 250 watts * 2,56 = 640 watts
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I would love to see the video. Let me know when you post.
thanks for the info but i believe, wind resistance is squared. so if you double your speed the wind resistance goes up by 4x but the amount of power required goes up by 8x, because the are covering twice the distance.
i will do, i have 8 videos in total i am working on, a complete build process in 6 parts, a shorter version more for inspiration and test riding. i will post them up when they are done.
I embarrassed myself again. You are right. i have to do some testruns again to figure out how many watts are needed. 250 watts is also good for nearly 30 km/h. So it would be 50/30 = 1,6666666 1,6666 ³ = 4,629 4,629 * 250 = 1157 watts
Need to make some videos again to get the right values from life recordings before i throw out more stupid stuff. And maybe the VESC’s current readings are not very reliable when it comes to max power output.
haha, nah its an easy mistake to make. 250w sounds about right to me but i do love seeing the number so id be interested in seeing your tests.
On your screenshots it looks like you didn’t set your min and max pulsewith!?
my build post is up and running as promised.
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