Evo turbo capacitor?

[joshzz]

Does anyone know what kind of capacitor they use for the turbos and do you have to charge them or is it like an extra battery?

I think I saw somewhere people selling 4700 micro farad caps. I'm not sure what voltage the motor runs at, but I'd get like a 9V or better to be safe.

I could be wrong, but this is off the top of my head.

[Rez]

Should go without saying, but if you're messin with caps, be carefull guys. Don't just toss em in. Read a book or something or you just might get bitten by the electron.

This is true, once a capacitor has energy stored, it will release if something crosses the electrodes. Most of them don't store enough to really do any damage.

But in this case, these are small enough that they can't really doing anything that bad.

[Namuna]

Originally posted by Jazz32
I think I saw somewhere people selling 4700 micro farad caps. I'm not sure what voltage the motor runs at, but I'd get like a 9V or better to be safe.

I could be wrong, but this is off the top of my head.

Okay, I'm going to show my ignorance here but...Isn't it generally a bad idea to send any more than 8.4v through an XMods pcb? So if you're using a 9V cap, doesn't that mean you're sending 9v of juice through the circuits (for however long the cap is rated for) ??

A capacitor will charge at the voltage that is sent through it. If you charge a 12v capacitor at 3v, it will output 3 volts. Basically that voltage rating is just where the capacitor will fail.

(I could be wrong, but this is what I was lead to believe)

Speaking of 8.4V, I just got my 7cell, stacked FET, evo running. It still uses a stage 2 with the highest gearing. I have about a 15' driveway that is really smooth. My roomate got home otherwise I would have opened the garage and doubled my length. There definitely isn't enough room to run. That stock motor gets really hot, my double stack FET's did too.... I might try to stack another FET on there.

i brought a turbo capacitor for my stage2 6cell evo and it goes like [word removed] of a shovel.

i also found out that i already have 5 of these turbos so i might sell them.

[Namuna]

Good for you p4tch, but there's a reason why you can't spell out that curse word you used...Because there's a word filter on these forums that pulls those out.

You chose to circumevent that filter, and that's against the rules here.

I'll ask you not do that again.

[Azimov]

Yah, all the info here so far is correct. Jazz32, well done.
Caps at these voltage/current lvls are no problem and completely safe. I haven't done any mods using caps, but the use is pretty straight forward.
The voltage lvl should be higher than the voltage you are putting in from your batteries. How much higher doesn't matter. Put a 1000volt cap on there and put 5VDC through it and you get 5VDC. Current storage is what caps are all about so the current rating is what is useful. 4700uF is very small and I would think the boost you get would be very short and weak. I would think you could go up to nearly 1F and get a good strong boost out of the hole.
I would think all you need to do is get an electrolytic capacitor. Thats the can type that has polarity clearly marked. Hook it across your battery rails, that is, in parallel to your entire battery pack, and you should be good to go.
But, I think I would experiment with hooking it to the neg side of the circuit in series as well, just to see what it does.
The idea is that a cap discharges much faster than a battery. Batteries discharge at pretty much the same rate until they are almost dead. Caps "push" the current out all at once (kinda) in a dump of power until it reaches the current discharge lvl of the batteries.

yeah soz but thats UK MIDS

[Rez]

My intent was that kids would bother to educate themselves. I don't really like the idea of people messing with caps when they have to ask for instructions (with pictures) to add a battery. Yeah, these capactitors are safe at these levels. But I could see some kid thinking, "man, there's a huge capacitor in this junk here" or something stupid like that, not realizing the potential danger.

[Azimov]

I don't really like the idea of people messing with caps when they have to ask for instructions (with pictures) to add a battery

Agreed.

But I could see some kid thinking, "man, there's a huge capacitor in this junk here" or something stupid like that

I would hope that anyone, at any age, that wishes to perform these kinds of mods at least research basic electronic components. We all have access to the information via the internet and there really is no excuse for not understanding what you are dealing with before you tear into it. That said, I still assume the person asking will do that research because it's his responsibility, not mine. I'll answer best I can, but ultimately, the use or misuse of the info is up to the individual. There are capacitors out there in the sea of techno junk that will zap you pretty good. Disposable cameras have a cap in them that is almost always charged when you come accross it and it will pop you a good one. I know. Old TV's have current storage in places that can kill you even after sitting in a junkpile for years.
So, know what you are touching before you touch it!

I only said 4.7 micro farads because that is what I had previously seen. A farad is a huge amount, one that could really hurt someone. 4700 micro is still a pretty decent amount.... much bigger and the physical size really starts to creep up.

[Azimov]

A farad is a huge amount, one that could really hurt someone.

Well, not really that much and at low voltages fairly harmless.

4700 micro is still a pretty decent amount.... much bigger and the physical size really starts to creep up.

There are 1F aerogel caps that are half the size of that 4700uF cap. 1F might be a bit much, but I'd experiment with different sizes just to see what the effect is. If it were me.

[Azimov]

Let me explain about my fiddling with capacitors. My experience comes from using them as storage in solar applications. I've hooked motors to solar circuits using caps ranging from 1000uF all the way up to 10F, which is the largest storage I could find on the net. I usually use between 3-6VDC with these solar circuits.
I've had a couple of mishaps with screwdrivers or x-acto blades crossing the leads on a charged cap and have gotten some good sparks, but never the slightest poke of electricity. At these voltage lvls, you can touch the leads with your fingers with no ill effect or even discharge of the cap.
Things get a little scary when the voltage is very high even if the current is very low. Thats why the caps in disposable cameras will bite you good. They discharge if you touch them bare handed. They're rated around 10-30,000VDC At something like 1000uF. Same with electric fences and tazer guns. Stupid high voltage, low current. This will kill you.
What we are dealing with is the opposite. Low voltage so so high current. Fairly safe.
Now let me explain why I would go upwards to the 1F range for a turbo boost. I've hooked many a motor to those caps and solar cuircuits so the cap dumps through a trigger and spins the motor. Caps in the 4700uF range will maybe spin the motor shaft 3-4 times. Thats ungeared, straight from the shaft. No real boost at all. When you get up to 1F or so, the motor will spin like a dervish for 10-15 seconds depending on the efficiency of the motor. With these cars motors, I'd say you would be lucky to get a 3-5 second boost.
I know you weren't saying 4700uF was the way to go Jazz, I've seen those posts as well and wasn't implying that you were mistaken. It's just that I know I have to hook at least three of those 4700uF caps in parallel in order to get several revolutions out of highly efficient motors.
Sorry for the long post, but I felt the need to clarify why I have little concern for the use of high current caps in this application.