Help me understand these Vesc settings

Do you have a VX2 remote? Or any remote connection via uart? That seems to interfere with the app

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I do have the VX2 and it’s quite possible it was connected. I read somewhere that bluetooth devices interfere with the app but it’s entire possible I had the remote on when it wasn’t working and off when it did and didn’t realize the remote would interfere with that as I believe it’s 2.4Ghz connection. The app does transition from motor config to remote config so it’s reasonable to surmise that the remote could be on for that process. I’ll check tonight.

They must have made the batteries with the thinnest of nickel strips as they appear to tear easily. This is an easy fix.

“Battery regen, set that according to the brake performance you desire.”

No, please don’t do this! Apologies if this seems aggressive or I’m just replying to a typo but you should set the “Motor Current Max Brake” to whatever you want/need for braking performance, but do not set the battery regen current above the rated charge current for your battery.

The simplified version is motor currents set performance in accelerating and braking, as long as you don’t exceed the motor current ratings you’re fine. Battery currents set battery safety limits. Do not exceed battery safety limits unless you know what you’re doing.

Rule of thumb: high quality 18650/20700/21700 cells last best when charged at 1A, and can usually accept a fast charge rate of up to 3-4A per cell. Check your specific cells if possible. If it’s a 3P pack, then 3 cells are charging in parallel so it’s 12A max before you’re almost definitely exceeding the specs. This 12A also applied to regen, I guess if the manufacturer of the pack (boundmotor) is happy to stand over 20A charge current that’s ok but it is not what the cells (think samsung, LG) are made for and not a good idea

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Yeah that may explain the 12A regen settings I saw on many 3P setups when searching for answers. Boundmotor has been really good thus far at providing information so I’ll leave the 20A regen as it is for now.

If you’re saying a 3P charging at max 4A per cell means a packing charging max of 12A then a 4P would be 16A, if I’m understanding this correctly. So absent battery specs this is the type of rule of thumb thinking I need in order to derive settings with those 3 cell types.

Yeah exactly, 16A for 4P is a decent rule of thumb. If you’re curious about learning more my main sources are datasheets for

  1. LG 18650 HE2 (the cells I use because they have a high discharge rate and were available cheap because they’re slightly older tech and not super high capacity)
  2. Samsung 21700 30T (relatively common, relatively modern 21700 cells)

Datasheets for individual components can be dense as hell because they’re generally only meant to be read by engineers focused on a specific project, but the first page of text and first table are usually interesting. The standard charge and fast charge currents are what we’re interested in

https://www.google.com/url?sa=t&source=web&rct=j&url=https://www.imrbatteries.com/content/samsung_30T.pdf&ved=2ahUKEwjIo_uX_pnwAhW7WxUIHcIkAQYQFjAAegQIBBAC&usg=AOvVaw2rGH-ByMzYovjjXkQfjKBH

https://www.google.com/url?sa=t&source=web&rct=j&url=https://www.powerstream.com/p/LG-ICR18650HE2-REV0.pdf&ved=2ahUKEwiy1_L6_ZnwAhVdRRUIHWMsAxQQFjAAegQIBBAC&usg=AOvVaw0sC6qS2xUGHgRUNeLLQcb0

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Oh and one last thing: a big part of selecting components when designing a product is validating it for your specific use cases, because the manufacturer’s specs can never cover every case. If boundmotor have put effort into validating these cells for use in a 20A recharge pack then it’s all good, they might have evidence to agree with the person above who said that because braking is a short burst you can exceed the charge current. But honestly there’s a reason the main charge current in these datasheets is around ~1A and the 4A is close to a maximum. These cells already only last 500-1000ish cycles, and I don’t think there’s any eskate company who’s got an engineering team that can overrule Samsung

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