I thought it was about time to start a thread on the amp draw of different setups. So include specs and how many amps you pull on average continuous and how many u peak.
average around 5 Amp draw on my 6S single SK3
12S single R-SPEC 6355/190 -> 30A peak
6S setup, enertion RSpec 6372
From the measurement I did when I had the wattmeter plugged in between the battery and the FVT ESC:
10-20 Ah when accelerating slowly and cruising (~250/500Wh) and 40Ah (900Wh) at peak (accelerating full throttle uphill)
On the VESC, initially I had configured motor max as 40A and then 50A but I had not enough power to accelerate strongly uphill (I weigh 95kg), after I changed it to 60A I never experienced cut-offs so I guess the max drain will be around 55A.
My question is, if I had a 12S setup then I could set motor max to 30-40A and not experience cut offs in theory isnt it?
Sanyo NCR 18650GA
yes in theory that would be correct it also depends on terrain and gearing too
@willpark16 you’re on a tear today … Go take a nap or something … Even better … Go Skate
haha just took my nap
So with amperages sounding so low, why does everyone use really high amperage ESCs? couldnt you use a 45-60A car ESC if you barely hit 40A?
To keep the mosfets (a.k.a. FETs) of the ESC cool.
They handle most of the current in the ESC, they switch and modulate the current from battery to motor (electrical side of the things, the main chip instead, the DRV in case of VESCs, sends low voltage pulses to them to control their output current)
im assuming everyone is using the vesc. This allows them to run there motor at its optimum
couldn’t you just mod one and add a massive heatsink ?
or maybe go crazy and do water cooling or submerged oil cooling
yes, people put small heatsinks that have adhesive tape on them (like these) or thermal glue to keep them cool, or even a piece of metal so the dissipation surface is increased, also if you add more code to the VESC that does extra calculations is recommended to cool the main chip down as well.
Im talking about a car esc, not the vesc
Yes, these things apply to any ESC, every ESC has a chip that is the “brain” of the ESC, and does the calculation for draining and outputting the right current based on the receiver’s input, battery and motor status, and that chip, like the FETs, has to be kept cool as well.
ah, i see what your saying now.
Chinese Spec Inflation
Average 600 watts and max out at 3500 watts when accelerating on a dual drive.
I’ve been planning forever to pot my vescs since then they wouldn’t be suffering the physical abuse that they get otherwise and according to Chaka and Vedder the vesc’s fets are the only heat source that I’d need to worry about and shouldn’t be potted.
The brain doesn’t get that hot?
I have so much potting resin but am still afraid to do it. Wouldn’t need an enclose just glue it to the board with the potting resin.
How fragile are the fets? I planned to have them exposed and just covered with stick-on heatsinks.
Main reason is lower amp car esc’s are less than 6s.
Hello everyone! A topic about what is the real amp draw / current needs for a system surfaced on another topic.
So, gladly @DeathCookies made a simple template for everyone to enter their data into
Although, it is still in beta stage and needs to be improved!
Any feedback / improvements would be great!
Poll for entering Amp draw data:
We don’t have a seperate topic for feedback / improvements yet, so you could contact @DeathCookies by messaging him.
I can invite everyone to our conversation, if someone is up to contribute more in creating this tool.