Archived: the OG noob question thread! 😀

There are several different ways, depending on exactly what kind of LEDs you’re using (bare LEDs that need a driver, or LEDs with their own current limiting such as the common LED strip), and how many LEDs you plan to use.

  • The vescs have their own internal power supply to run themselves, and they can supply up to 5V, 1A for external items such as receiver, hall sensors, and, yes, LEDs. I’d stay well under that 1A limit though, don’t want to risk stressing the vesc’s power supply.

  • Using a dedicated switchmode regulator like Brian mentioned is a good option if you’ve got 5v or 12v LED strip that requires no special current limits.

  • If you’re using bare high power LEDs (like for a headlight, or similar. “high power” means more than ~0.5w per individual LED) with no internal power circuitry, you can get dedicated constant-current LED driver modules that will run from the main battery just like the above. These are what I used for my headlight and tail/brake light.

  • If you don’t want to screw with any of that, you can always just get a small USB power bank and some USB powered LED strip, and recharge the power bank regularly.

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link please, like @wafflejock i suck in electrical stuff so i prefer to be directed to what works and try and understand from there :grin:

Well, that is not very redundent is it :stuck_out_tongue_winking_eye:

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https://www.digikey.com/product-detail/en/xp-power/LDU5660S500-WD/1470-2178-ND/4488557

Keep in mind, this is only for bare, high power LEDs with no current regulation of their own, like what you find in headlights, flashlights (bright ones) and similar (The headlights, flashlights and etc all have something like this in them to drive the LEDs). This will not work properly with regular 12v led strip or whatever. For that, just use the DC-DC converter Brian posted. These still need some electrical knowhow to use properly - I recommend reading and digesting the datasheet.

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From the vescs 5v 1A output you could theoretically run ~16 RGB leds at full white brightness. But if it’s a good idea is another story…

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Hi guys I have a couple of quick questions about programming my vesc.

A little back ground, I have a 12s 4p 30q battery built buy tinnesinker.
The vesc is a flipsky FSESC 4.12 50A https://flipsky.net/collections/electronic-products/products/torque-esc-vesc-ÂŽ-bldc-electronic-speed-controller
And a 3000w 150a max output 6374 200kv motor from ebay ebay.com.au/itm/352800722124?ul_noapp=true.

Am I safe to set the max amps for the motor to 150a? this seems really high.
Using the esk8 calculator it says my max amps for the battery pack should be 80a is that correct? is there any advantage to setting it lower like 75a to give the battery a little bit of a breather?
Finally the deadband is to 15%, do I need it so high or at all? what do you set it too?

Thank you all in advance I would have just bought a boosted board like everyone else if it wasnt for you guys! I love your work.

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Excellent question. This thread has heaps of great info, and heaps of missing info… but in a nutshell, battery amps and motor amps are not the same thing.

Basically, you can set your motor amps to whatever you like at the risk of melting your motor. Set it to 150 and see if it gets hot… it probably will on a single drive. But be aware that limiting your motor amps too low will drastically restrict your motor performance.

But your battery amps should definitely be set to within your battery’s capability.

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can someone do this nice math for me :sweat_smile:
with a 12s of 40t, will i max out the possible power of a 170kv 6374 3510W 65A max motor?
thx!

Depends how many parallels of the 40T you have, 1p you’ll be only giving the motor a constant ~35a, 2p @ ~70a etc.

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It just depends on the circumstances of riding.

The motor pulls the amps. The amps don’t just go to the motor because the battery is capable of outputting that much. How much you weigh/your throttle settings/how hard you’re throttling/grade of incline all go into it.

As @itsrow has said though, you’d need at least 2p groups to pull that.

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Thank you both.
The full question is this;
I am 60kg, my board is a mtb, will be used as such going up steep hills off road.
2wd
12s6p 40t
Unity.
Imagine i max settings to the most reasonable it can go.

should i choose a

  • 3510W 65A max 6374 170kv
    or
    -4100W 80A max 6380 170kv.

no point of having the extra weight of the 6380 is if i won’t even use the limits of the 6374.

the vesc does a voltage change depending on the speed of the motor (lowering the voltage but increasing the amps) between the battery and the motor… so you can safely set the motor max to 150a per motor, and the battery max to 80a per motor without exceeding the battery limit per motor.

unfortunately on a standard vesc 6, hidden in the firmware is a 120a motor current limit, so even if you enter a 150a motor current limit in the settings, this value will be lowered to 120a motor current limit without much indication this has happened.

straight from the vesc-project.com forum:

if you set the battery limit less than the motor limit, you’ll lose some throttle range at the higher speeds because sustaining 120a at those speeds requires more than 80a battery amps.

for that reason i recommend not exceeding 80a motor limit per motor and 80a battery limit per motor.

that said, 80a per motor will likely give a large amount of torque at full throttle, so you might want to try something lower like 50a bat and 50a motor at first, and if that’s not enough torque for you, try increasing the settings while keeping them equal.

and remember, the battery limit setting is per motor

& the motor current limit setting basically determines how much torque you have at full throttle assuming the battery current limit setting allows that much power

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It’s a MTB, you already have a 12S6P of fucking 40T. Weight doesn’t seem like the biggest concern… Get the 6380. Higher quality, longer lifespan. I believe higher efficiency as well.

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Hey I know some electrical things! I think I only fried one Arduino Mega and cooked an alligator clip off a wire getting this test lift rig put together:

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well then damn me

i @ ed the wrong person lol
@whaddys we are in the same boat :rofl:
Sorry @wafflejock!!!

I take the oputunity to ask another question though haha
i have 2 builds, 1 mtb, 1 street/at build both with gear drives
which vesc would you use for the mtb

  • Unity
  • OG Focbox 1.7

0 voters

cheers!

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While I agree with @glyphiks and @professor_shartsis in principle, they seem to have overlooked the fact that you have a 50A vesc4.12. That is your limiting factor, not the motor or battery. With that controller, I wouldn’t set the battery current any higher than 40-50, and wouldn’t set the motor current higher than 60-75 at most. That vesc just isn’t built for any more power - they were designed for cheapness, not thermal performance. No heatsink, and no practical way to add one.

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true— the hardware limits file in the firmware of a 4.12 vesc has lower battery and motor limits than a vesc 6— likely 50a or 60a bat per vesc and 120a motor per vesc, but it won’t be able to sustain these limits continuously as heat build up will likely lead to thermal throttling if those current limits are sustained

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Touche :ok_hand: what would we do without you :joy:

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How does that power switch on the COMM port of the VESC 6 MK III work? Which cables do I have to use and where do they connect to?

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@PixelatedPolyeurthan If you do have special current limits, you can use this one

instead which is CC/CV instead of just CV like the other one I linked above. But this one doesn’t have mounting holes :imp: Aside from no way to mount it besides wrapping it in foam and cramming it in there, this one is very very good.

CC/CV = Continuous Current, then Continuous Voltage as load lowers (just like a lithium charger)
CV = Continuous Voltage

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@trampa 28jasons

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