Quark fried, blown capacitor...

[zeropointbug]

AAngel: You bet, you can cut a little insulation from each lead and stick each cap lead into the wire strands and solder that. That's the only way I can think of at the moment? And yes, those on eBay that i linked, they will work very well, they are very low-esr caps. Kinda nice if one could find a better supplier, so you wouldn't have to buy 200 caps when you only really need two!

I totally agree with you that an esc like this cost, and performance should be better able to handle these vehicles. But the reason they can't put larger caps on it, is simple, space. They should make a little kit, or a "Quark" aftermarket cap they can sell if you are using a large RC car. I would only benefit them, IMO. The other reason this esc fails, is the heatspreader problem, if they fixed that, it would be 100% better.

The smt caps are useless for this, just try making a connection with those little tabs on them! :024: Most smt caps are solid polymer caps, which at the lower voltages (<16v) they have really good esr ratings, and they are very durable. Motherboard manufacturers are using them lots now, video cards have used them for about 5 years now. Nothing that will work for this app. though, the low-esr electrolytic outperforms them at these voltages, or at least what I have seen.

I don't have my Quark yet, so I've never seen one up close yet. Aren't the battery leads just soldered to a pair of holes in a PCB?

Anyway, are those the caps that are needed? The 300uf 35v ones linked to on ebay. It would seem that the price isn't bad for 200 of them.

[zeropointbug]

I have decided I am finally going to give Ultra-caps a whirl! :027:

I am going to get the 140 Farad (x10), I'm only using 8, but the quantity pricing is better for 10, only $14 more for 10. $150

I am figuring the voltage drop on a 100 amp load will be less than .4 volts.

HERE is a link to the Online Shop

17,500,000uF anyone?:018: :005:

[zeropointbug]

Originally Posted by AAngel

I don't have my Quark yet, so I've never seen one up close yet. Aren't the battery leads just soldered to a pair of holes in a PCB?

Anyway, are those the caps that are needed? The 300uf 35v ones linked to on ebay. It would seem that the price isn't bad for 200 of them.

You could also use these, if you are using 4s LiPo. They are 25v/820uF, your choice.

Yup, those are the caps you need, they are the 330uF/35v.

The wire leads go through a hole at the end of the case, which is plastic. The wire solders adjacent to the pcb board. HERE is a pic.

Thanks for the pic. The Quark looks like it'll be easy to work on. I suppose, the first thing I'll do is upgrade all of the leads to deans wet noodle and add the caps.

[zeropointbug]

Originally Posted by AAngel

Thanks for the pic. The Quark looks like it'll be easy to work on. I suppose, the first thing I'll do is upgrade all of the leads to deans wet noodle and add the caps.

The wire leads don't need to be changed, it's good wire.

Another thing, when soldering, I would make it so the cap is pressed right up against the case of the Quark, and the cap is perpendicular to the wire leads.

[Patrick]

Originally Posted by zeropointbug

I have decided I am finally going to give Ultra-caps a whirl! :027:

I am going to get the 140 Farad (x10), I'm only using 8, but the quantity pricing is better for 10, only $14 more for 10. $150

I am figuring the voltage drop on a 100 amp load will be less than .4 volts.

HERE is a link to the Online Shop

17,500,000uF anyone?:018: :005:

Does this mean your going to use 8 in series to get 20volts and use them as your batteries? (power the motor by themselves) :eek:
Sound interesting if you are. They don't have the enery density of good batteres though do they? Still pretty light if there 29grams each, but I have no idea how or if you can compare mah to farad.

[zeropointbug]

Originally Posted by Patrick

Does this mean your going to use 8 in series to get 20volts and use them as your batteries? (power the motor by themselves) :eek:
Sound interesting if you are. They don't have the enery density of good batteres though do they? Still pretty light if there 29grams each, but I have no idea how or if you can compare mah to farad.

Just using the capacitors alone, you would have one good high speed run; the charge (voltage) is linear to the amount of charge left, intrinsically, that's what a cap is.

I would use them as a hybrid pack, battery delivering the energy (as a low constant current), and the caps delivering all the peak power. Doing this, the system voltage will stay very high, near nominal voltage, with less than .4 volts of vdroop. It would be neat though, you would have off the charger voltage available for power after you charge, for a few moments.

You gain a little energy from the cap itself, and also from less strain on the battery, it will deliver it's true (or very close) mah rating, as well as little wasted energy due to vdroop. So, if you were to use an eagletree to measure the running performance of the battery without ultra-caps, it will look like THIS

Then if you add the ultra-caps, it would look something more like THIS, more of a constant discharge at low rates, and higher voltage.

I just have to ask. If running all of these caps is so beneficial, why hasn't this been visited before?

It seems to me, that if there are so many benefits to running all of these caps, you could just solder small copper posts or bars on the rather large solder pads of the quark to accommodate four or so capacitors and then solder the battery leads to these bars.

As for the arcing, I run a junction box of sorts on my truggy and facilitates quick battery changes. The esc and battery connectors plug into the junction box to complete the circuit. If I run my fans from the junction box, the fans should drain the caps when I disconnect the batt and prevent the arcing when I re-connect the batt. Is that right?

[zeropointbug]

Well, these small high power ultra capacitors are relatively new. Don't ask me why no one has tried it, as you can see, not very many ppl are interested in them. We won't know how well they perform in real-world unless someone tries it, I am.

As for your connector arcing, it WILL happen when there is no voltage in the caps, if they are charged, it won't happen. The Quark itself self discharges the caps, no need to do it. Your fans will only run for like a second.

[GriffinRU]

Originally Posted by zeropointbug

Well, these small high power ultra capacitors are relatively new. Don't ask me why no one has tried it, as you can see, not very many ppl are interested in them. We won't know how well they perform in real-world unless someone tries it, I am.

As for your connector arcing, it WILL happen when there is no voltage in the caps, if they are charged, it won't happen. The Quark itself self discharges the caps, no need to do it. Your fans will only run for like a second.

Why nobody? I used them they are great but they are not cheap. Old link

[zeropointbug]

hmm doesn't say that you are using ultra-caps. Which brand/series did you use, and what did you use them in?

[GriffinRU]

Originally Posted by zeropointbug

hmm doesn't say that you are using ultra-caps. Which brand/series did you use, and what did you use them in?

same caps
I was using BPAK0058 E015 58F 15V on E-Maxx.

[zeropointbug]

Oh, you were using one of their modules? IC How many caps total did it use? It shows 58F, but you would need alot of caps to get that, considering the series requirements for voltage. What setup did you have? Little more info?

[GriffinRU]

Originally Posted by zeropointbug

Oh, you were using one of their modules? IC How many caps total did it use? It shows 58F, but you would need alot of caps to get that, considering the series requirements for voltage. What setup did you have? Little more info?

Modules selector

My module pdf

6 350F Ultra Caps with balanced circutry and wiring for series connection.