Vesc battery limits

I saw on the forum that the vesc 4.12 can only handle 27 amps? I want to set motor max and battery max higher (right now they are at 60 and 25) because I think they can handle it, but I guess the vesc can’t. Could someone confirm this is the case? I want these settings as high as i can put them safely. I’ll post the relevant information below. Thanks!

vesc 4.12 2 3s 5000mah 20c lipo in series 6374 192kv motor

From what I’ve read, the motor max could theoretically be 4032(motor rating)/12.6(pack voltage)= 320A but obviously the battery cannot output this (I plan to add one or two more 3s packs in the future btw).

By a similar argument, the battery should be able to handle 20C * 5Ah = 100A.

Is the only answer that I need a higher battery voltage so that fewer amps are drawn by the motor? Or are 60 and 25 really a starting point that you then dial for the best performance? Also, I have some heat sinks I could attach to the vesc, but is that overkill? It should just limit current if it starts getting hot and I don’t think I’m pushing its limits with 6s.

Wow. that was a lot of questions for one post. Sorry, I’ve gotta learn this stuff somehow. TLDR: Is it ok to run vesc 4.12 at higher settings than motor max = 60 and battery max = 25?

I got it from diy electric skateboard

Motor current refers to phase current which will always be higher than battery current. I run mine at 60/60 and it barely hits 20 amps battery. Battery current is approximately equal to motor current times duty cycle. So for example, at 10% duty cycle and 10A battery current, phase current is 100A! You have to remember that the motor is being switched on and off at a few kHz with a good chunk of it being off. Battery current is basically the time averaged motor current. Of course at 100% duty cycle motor current = battery current which is where that limit finally kicks in.

The 27 amp VESC rating is battery current.

It’s okay to run it with 60a motor max and 25a batt max. Mine is a maytech and I’m running 30a batt max without problems.

But are those the upper limits? It seems like you are saying they are but then you run yours at 30 so is it a soft limit or will I definitely fry my vesc if i go above 25?

No, you won’t fry your vesc if you go over 25a. The vesc is rated 27a continious before it goes nuclear. This means on a setup with a 10s battery you can have 972 watts of power. Most vescs nowadays can output far more power. I’ve seen people running 40/50a batt max. How much your battery can output also is a factor in power. If your battery sags alot under load you won’t get good performance. I hope this answers your question.

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