VESC FAQ | How Many Capacitors & What uF

And that point will Nordle keep away from Enertionboards in the future. It’s too easy to find a more reliable seller. My eye didn’t catch this. Thanks, but somehow pity.

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please link to that page so i can check it out, thanks

Here you go http://www.enertionboards.com/electric-skateboard-parts/pulleys-belts.html

Can you tell me the capacitance and farad from this belt? :joy: I’m joking…

ok, got it, yeah it should say 256-55t

Probably i could get a VESC with a cap only supporting 50v? Well, i did not buy such a product and will have a big problem because i just ride on 12S.

Do you have an idea on how to handle my problem if i should get a 50V version of my 3 ordered and shipped ones?

Hi, if someone is not confortable with the capacitors delivered with the VESCs and have access to an electronic components store, just buy new ones and substitute them. I don’t think is that expensive if someone feels better and thinks is the right thing to have.

Well, normally i wont complain it that much… but this time i am a bit mad…

One delay hunts the next delay … ok, the VESC is fairly new and so on but @onloop could have told the costumer that they change something in the product! He did not.

Now i have payed for a product which i dont get as described. That is what i dont like. Now you tell me that i should take responsibility for others faults?

To put it in a netsheel: I am not totally freaking out. i am just a bit mad about the behavior!

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I feel with you! All the waiting, no problem. But this made me freak out! :imp:

buy some 63v or 100v Caps from some nearby online electronics store & send me the bill.

I really don’t know people are getting upset here, @onloop is following his manufacturer’s recommendations. I’m pretty dam sure the guy who proposed this recommendation is an electrical engineer. This modification should be trivial for you guys.

Got my VESCs yesterday and they’ve got 63v caps! First thing I checked out of curiosity after reading this, Jason apparently worked it out with the manufacturer very quickly! Or they have run out of 50v caps and now only have 63, so I think everyone should be alright.

So would it be possible to get confirmation, hopefully from @onloop. If I have 63v capacitors on Enertion VESCs (which I do), am I safe to run 12S?

Would be a nice bonus if true, as the specs on the Enertion site state 10S max, so I was aiming for 8S, but the motors can handle it, so if I can stick another 4S LiPo on there that would be great.

incorrect… the impedance of a cap or inductor refers to resistance but also reactance “X” - the time-varying phase shift of the current or voltage it’s resisting… that doesn’t get “spent” in the form of heat.

The ESR or Resistance is the actual resistive component of the inductance (think total Z = 1/jwC + ESR) or X + ESR

The ESR being high means, when you try to pull a lot of current, V=IR will be your voltage drop from the cap internals out the wire, to your VESC. So if there was 0.1 ohm ESR and you tried to pull 10A out of a 40V cap, you would only “see” about 40V - 0.1(10) = 39V. Imagine an instantaneous inrush of 100A and you lose 10V!

If you start combining a bunch of caps into one package or picking cheaper, larger values you typically have an increase in ESR which not only heats up your cap (shortening the life) but is less “real” - the capacitance isn’t really at the voltage you want after it is burnt across the ESR. The cap heating effect is why your capacitor has a “ripple current” rating meaning how much watts it can passively dissipate as it is constantly burning back and forth as current moves across it. I doubt builders like Jason are measuring these values in their design. Note that for every 10 deg C you increase the temp of aluminum electrolytic caps the lifetime is cut in HALF!

Definitely study up on reactance vs impedance vs resistance as you finish your EE degree as people love to ask this sort of shit in technical interviews :wink:

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Does that mean that multiple capacitor might be less preferred than a single, big capacitor because its will combine the ESR, increase the resistance between positive and negative and means an increase in voltage drop?

Sorry if its a stupid quesion.

Multiple capacitor do “combine the ESR” as you say, but they combine in parallel meaning overall resistance goes down.

Imagine 1 guy with a pile of 100 snowballs VS 10 guys with a pile of 10 snowballs each. Which would you rather get in a snowball fight with :wink:

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My bad, I’m not sure why I typed “increased” :slight_smile: what I have in mind is reduced

So does that mean that bigger capacitor is better since its just a single capacitor or the ESR is relative to farad?

Sorry I have no idea about this. I only know the basics of resistors. Parallel is subtraction and series is addition :slight_smile:

Series may be addition but parallel is hell no subtraction (If I start with 1 ohm and put two more 1 ohm in parallel do I get negative resistance? :wink: )

Bigger cap is better from an energy standpoint - And you can always pay more money to get lower ESR for any given size cap - but if you could choose 1x660uF or 2x330uF , the 2x will probably deliver it more effectively (inductance is also a factor with long package leads and high di/dt). The only reason to go single big package is cost.

Ok, my bad again. Heh. But 2x1ohm in parallel is 0.5ohm. Is that right?

I should start reading more :slight_smile:

But I appreciate your insight :thumbsup:

Hello guys,

I’ve read many posts about caps as my vescs are the ones with a big cap instead of 3 smaller ones.

At the moment I would like to change my caps but I am wondering what is the typical Vue for a low esr for the vesc.

0.1ohm is what we should aim for? Lower? I’m trying to figure out what values I should be looking for.