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Old 06-21-2005, 08:03 PM   #166
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Awesome thread, LOTS of good info here. I think I have to start over though -JB
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Old 06-21-2005, 08:35 PM   #167
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dont lectricity start up in outer space somewhere? i hear tell its all stored in a spaceship and sent down here ,,,,,,,,lol....I apologize ahead of time just like i do on the drivers stand before the race..
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Old 06-22-2005, 12:35 PM   #168
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Quote:
Originally Posted by rcnewb2004
anyone have any real esr numbers to compare just for the sake of argument?
Try this one here. Link to the ESR chart I posted on page 4 in this thread.
Quote:
Originally Posted by andsetinn
Well here is a link to a ESR chart. Link. This is the same link I posted on page 3 in this very thread. It lists worst case scenarious for new capacitors.
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Old 08-05-2005, 12:28 AM   #169
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will these caps decrease runtime????
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Old 08-05-2005, 03:05 AM   #170
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Nah, they'll make your car go faster, run longer and make you a better driver.
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Old 08-05-2005, 03:42 AM   #171
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hello.. now i am using NOVAK GTX...which capacitor should i use? show me the picture and tell what volt to use..thanks..
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Old 08-05-2005, 05:00 AM   #172
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Quote:
Originally Posted by andsetinn
Nah, they'll make your car go faster, run longer and make you a better driver.
Some people think the bigger the capacitor the faster or longer they go ? I don't think so. It makes your car messier and heavier.

Some ESC don't need extra capacitor like Keyence Rapida, Ko Propo VFS 1, LRP QC2, etc but they run as fast as GTX, GT7, or any ESC with big azz caps.

Honestly, I was capacitors believer too in the past. But now, I don't. My pit work is simpler and my car is as fast as before.
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Old 08-05-2005, 07:01 AM   #173
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Quote:
Originally Posted by asw7576
Some people think the bigger the capacitor the faster or longer they go ? I don't think so. It makes your car messier and heavier.

Some ESC don't need extra capacitor like Keyence Rapida, Ko Propo VFS 1, LRP QC2, etc but they run as fast as GTX, GT7, or any ESC with big azz caps.

Honestly, I was capacitors believer too in the past. But now, I don't. My pit work is simpler and my car is as fast as before.
I agree with you asw7576

The cap stores up energy from the motor when you back off the trigger or when we brake and the next time you accelerate this energy is released in the form of "acceleration punch". Too much punch can make your car harder to drive (power cap too big). I'm running a QC2 with the World's kit on it. When I went from the small cap to the big cap I had to adjust the acceleration profile as it became too punchy out of corners. I'm not convinced that it would add to longer runtimes, if the cap wasn't installed, then this energy would be pushed back to the battery.
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Old 08-06-2005, 02:35 PM   #174
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Zax. use the largest capacity (measured as uf) capacitor you can find with the smallest physical size.

asw7576. I was kidding.

2-Bad. I'm an electrician. I think you misunderstand how capacitor works.

Last edited by andsetinn; 08-06-2005 at 02:50 PM.
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Old 08-06-2005, 05:06 PM   #175
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Quote:
Originally Posted by andsetinn
2-Bad. I'm an electrician. I think you misunderstand how capacitor works.
You must know a lot then, Enlighten me .......
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Old 08-08-2005, 02:56 PM   #176
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Quote:
Originally Posted by 2-Bad
You must know a lot then, Enlighten me .......

Well. You should read this thread from the beginning. I'll just say this. Capacitor that is connected to the battery does not store energy from the motor when you back of the trigger. The reason the punch changes is because the capacitor helps the battery to maintain voltage when the throttle is punched. The battery charges the capacitor.
You had the effect right, (larger capacitor = more punch (up to a point (it's not black or white))) not the cause.

I personally think the ESC software is badly designed if it "needs" capacitor, but that's my opinion.
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Old 08-08-2005, 05:58 PM   #177
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Quote:
Originally Posted by andsetinn

Capacitor that is connected to the battery does not store energy from the motor when you back of the trigger. The reason the punch changes is because the capacitor helps the battery to maintain voltage when the throttle is punched. The battery charges the capacitor.
Oops , yes your right, I just assumed it was connected across the Batt/motor + & the motor-. Looking at it again and its across the batt +/-.

Sorry, I stuffed up.... It will discharge under high battery demand (acceleration) and act more like a filter and maintain batt voltages better, theoretically improve runtimes, but I'm guessing this effect wouldn't be much (nothing significant).
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Old 08-09-2005, 03:10 AM   #178
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"nothing significant" can be the difference between winning and losing.
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Old 08-22-2005, 07:30 PM   #179
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Hi

Can anyone help me select an appropriate cap for 12 t mod and silver can stock? My guess is 4700uf for stock and 10000uf for mod. is this right?

thanks
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Old 08-25-2005, 10:21 PM   #180
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A 12T motor draws a lot of current. You need at least 10000uF.
http://cgi.ebay.com/ws/eBayISAPI.dll...tem=3190750340
(From the top link.)

You will notice the difference with the 10000uf, but it may be worthwhile to go even bigger.
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