Okay so I was just randomly playing with my board, which is currently in a state of repair. Was just spinning the motors up, one of them would spin some times and wouldn’t other times. Then a loud pop with some smoke, and she’s fucked. Can anyone help me figure out what I did wrong? This is my first time playing with VESCs, so I had battery amps set to like 30A
I know I’ve blown the DRV, just wondered if anyone had any idea of why it happened so I know to not do it again
If you were running it on the bench you may have exceeded the 60k erpm limit…
Did you go full throttle without any load? What’s your battery and motor values?
It’s a clone and when you look at the placement of the FETs, it’s not made very well. The two FETs (lower right corner are nearly touching each other). It would not surprise me if this is not the only issue.
Settings, what did you do, vendor, brand?
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Does setting an ERPM limit in vesc-tool stop this? Or is it more of a soft limit?
Yeah I did, that’s probably what did it.
12s5p 30Q with SK8 6364 190kV on FOC
Motor Max 50A Motor Min -30A
Batt Max 30A Batt Min Regen -2A
I can now see how it seems pretty clear this is my fuck up. I just want to be able to learn as much as possible to help in the future
Never blast it on the bench… and 12s foc is a very risky business…
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Time for that upgrade to VESC6 I think, before my build is even completed hahaha
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And -2A on the battery min will not give you any brakes. This value defines the strength of the brakes at speed. The motor min becomes more dominant at slower speeds! It doesn’t help to use high motor regen values and low Batt Min Regen values. The braking energy needs to be stored somewhere. If you close that door, you will not have an brakes when you need them.
12S FOC is no issue if you use proper hardware. Clone HW 4.12 ESCs can’t handle FOC at 12S really well. Chances are high that you fry the system.
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Not riding the board yet so not having brakes isn’t an issue. What settings would you recommend for my hardware?
Twin or single?
Twin 10chars
Run it in BLDC if you use HW 4.12 Assuming you use a 12s5p pack from 15A rated original Samsung cells:
Motor max 55 to 60A Motor max Regen: - 30A Battery Max 35A (each ESC sucks 35 A, which results in 70A for the Battery). Battery max Regen. -25A to -30A (about same as motor regen will result in more linear brakes)
The battery will not the high currents for a long time when you brake. These are very short spikes only.
That is not an over erpm issue. That set up should not exceed the limit.
That is a faulty vesc. Get in touch with them. They are good people and will help you out.
Well would I contact Flipsky directly or the random eBay seller I got it off?
These guys
If you look at the data sheet for the 30Q, the max charge rate is 4A, so at a 5P pack, should be 20A.
I’d personally set this to -20A to not damage the cells by charging them too quick. I have -12A on one of my boards and feel like it’s enough brakes for most situations. -20A should be plenty especially of you are used to “push” longboarding with no brakes.
Adding onto my other comment. You should leave the motor max regen at -70A (or whatever your motor is rated too). The duty cycle will make motor amps high and battery amps low during slow speeds.
For a dual drive here’s my recommended values (each esc will have these same values)
Motor Max: 70 amps Motor Max Regen: -70 amps Battery Max: 37.5 amps Battery Max Regen: -10 amps