Back to the drawing board. Need some pro advice

Esk8 Electronics
#1

I’ve been sitting on some older hardware and need advice regarding BLDC vs. FOC mode and 10S vs. 12S.

Waiting forever in anticipation of the Carvon EVO and then getting royally shafted by Jerry really took the wind out of my DIY sails (yes I’ve been procrastinating that long), but now that I have a beautiful enclosure thanks to @BigBen, it’s time to get serious again.

I’m an experienced non-motorized rider, and want to focus on a “push assist” build.
Obviously hub motors would be better suited over belt drive for this mode, however I don’t want to go overboard on my budget.

I have a couple Enertion 4.12 VESCs, 50x 30Q cells, and a single SK3-6364-190kv currently at my disposal.

Before I consult a local battery builder and order a Daly BMS, I’m wondering if I should stick with my original 10S5P plans, or move to a 12S4P model :thinking:

My recollection is that VESCs are best suited for BLDC and 10S.
My motor is also spec’d for 10S, however if memory serves correctly, some folks claimed to run 12S on it without issue.

Considering my focus on push assist, should I upgrade to a newer ESC in order to run 12S and/or FOC mode? Thanks in advance!

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#2

There used to be a really great build tree calculator available at: http://esk8-dresden.de/poe.html
Is there anything comparable today?

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#3

This is true of the older V4 like you have.

Ideally, yes. But do realize that no one to my knowledge other than Mellow has succeeded with a push assist implementation.

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#4

10S Vs 12S isn’t much of a difference for the motor, as long as you don’t exceed its total power limit or spin it way faster than the bearings can handle it doesn’t much care. I have 10,000 RPM in my head as a rule of thumb upper threshold for the “normal” bearings we use, you may be around 9-10k at 12S

There are other considerations like the FOC/BLDC operation and older ESC compatibility as you mentioned, and even in the motor there are different efficiencies and characteristics of running different voltages and adjusting gear ration. But roughly speaking, the motor seems like it should be fine at least

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#5

I think some people around here set the ramp down time in VESC to a few seconds to sort of imitate that, but haven’t tried it myself

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#6

I set it to 30 seconds one time and it didn’t work as expected unfortunately.

I’m always chasing the push assist dragon. One of these days I’m going to be weak and buy a loaded unlimited setup

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#7

Given those things are now out of production and were expensive to begin with, you may end up paying silly money for 198Wh in a year or so :grimacing:

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#8

Did you try hooking up a Wii controller like Low Guido?
I bought a cheap clone controller for $2.95 off of eBay some time ago, so at least the barrier to entry for testing is pretty low.

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#9

Nah I have not. Just used a standard ppm remote.

#10

Better make it sooner rather than later before they are true unobtainium

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#11

all their motor are sold out already

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#12

It’s been like that for a while now. There are a few shops selling completes with the kits though.

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#13

So, if I wanted to go FOC and/or 12S, would a Flipsky 75100 be my least expensive and acceptable option?

Is FOC at 10S possible with the VESC 4.12, or am I asking for trouble?

#14

Flipsky is never an acceptable option if you value your cash and your skin.

The maker x dv6 is a great option for 12s tho.

#15

So, you want to buy the ESC twice? If that’s the case, then just go ahead and get an expensive one the first time. :crazy_face:

#16

A single VESC 4.12 will do just fine at 10S. The thing you will be lacking the MOST with a single 6364 will be brakes, and you say you’re

so I wouldn’t worry too much about that. I would focus most of your energy on the deck+enclosure and the battery. Get those two things right — and you can upgrade later if you want to in regards to the drivetrain and ESC.

For a single motor I recommend rear heelside placement.

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#17

Turn down motor current to 12A and you’re there already

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#18

Exactly. I already have a 2013 Landyachtz Evo deck and single stack fibreglass enclosure from @BigBen

I just need to decide between 10S5P or 12S4P since the pack can realistically only be assembled once :wink:

That’s good to know, thanks. I was more worried about initial push resistance and if running FOC would allow for a lower torque start.

#19

50 cells is more than 48 cells. 10S5P for the win.

Now, if you test all the cells and one or two are weak (common with new old stock 30Q cells) then a 12S4P is a slam-dunk. Leave the weak cells out of the pack.

#20

That VESC 4.12 will do 12S in BLDC only mode (and FOC or BLDC at 10S) and no matter the mode or voltage, keep battery current under 25A.

20A is even safer if you run 12S BLDC.