JesseT

Overkill in the size is quite common as it seems. However the type of the capacitor is much more important. It should be a high frequency or a low-impedance capacitor. Changing to a huge capacitor of the wrong type can be a step to worse from the stock capacitor.
On the other hand, no capacitor will make you win races.

Geetoo

iTrader: (1)

Got my caps in Hong Kong which costs around US$5 only. Its a rubicon brand.

JesseT

I got my dyno to completion and I made a few test with caps. Instead of the normal power supply I used a speedo and an old blue Panasonic 3000, because of it's high internal resistance. The motor used is a 13x3 Corally. I dyno tested the power got out of the motor with three power level settings that approximately match 1/3, 2/3 and full throttle. All measurements were done with and without a cap. The cap used was what I normally use, Rubicon ZL 4700 uF. The ZL series was the best I could find a year ago.
From the results it can be seen that the improvement is massive on partial throttle, especially close to the 50% pulse width. At full throttle no difference was noticed. I also set the motor to run with a constant low speed and swithced the cap on and off. The power incresed and decreased accordingly. I hope I have proved my point now.
Best regards, JesseT

dw

are the1/3 power lines labelled the right way round?
According to your graph 1/3 throtttle is better without the cap.
2/3 throttle shows an improvement with the cap.
If the graph is labelled right then 50% throttle would give little to no difference in performance.

JesseT

Yep, they are labeled wrong. I'll fix it...
Corrected...

RC Nitro

JesseT & dw:
Thanks for the info. Can you clarify some stuff for a newbie. I know little about electric cars, I am a ME not an EE

My experance stems from a HPI pro I had years ago. ran a midnight 2 motor that I had to solder 3 cap to. I have a Quantum competition in the car using a green machine 3. This has the caps already in the end bell. Do I need to solder the caps that came with the controller to the motor???

Thanks for any help.

David Galdo

iTrader: (15)

JesseT :: Could you demonstrate the affect a cap has with a stock motor? Just for comparison to a Mod motor.

JesseT

RCCadet:
Sorry, no. I don't have a single stock motor. A guess the effect is pretty much the same, for the exception that stock class racing is done pretty much using only full throttle, and this is where the capacitor of the ESC plays of no role.
RC Nitro:
Don't confuse the ESC capacitor we are talkin about in here to the capacitors that are on the motor. The motor capacitors are to eliminate radio interference created by the motor. These are very much needed for proper operation, but the type of them is not crucial. If your motor already has capacitors, you're fine. They don't need to be the ones that were supplied with your ESC.

David Galdo

iTrader: (15)

I suspect the cap is a marginal or useless attachment on an open large flowing track but for the tight and small tracks it may be of some benefit where full throttle is rare.

RC Nitro

JesseT:
I did, thanks very much for the clarification and the info!!

He-Man

Would soldering the schottky diode on my Cyclone to the soldering post be the same as soldering the the diode to the endbell? Would this hurt performance of the ESC or motor?

Geetoo

iTrader: (1)

I had a mistake in soldering my schottky diode to the motor with wrong polarity. I noticed everything went wrong but had a few laps with it. Will this damage the ecs and motor?

Doraemon

Garet. okay lang yan... kung tumakbo pa yung ESC mo ulit after mo makabit nang baliktad yung diode, edi okay pa yan! (kung bakit kasi baliktad magkabit eh..)

Yung motor mo, walang kaso yan! slave lang ng ESC yung motor eh... ayos lang yan! sige, ulitin mo, tingnan mo, hindi masisira ang ESC mo at Motor mo... dali ulitin mo!

marvi

iTrader: (82)

geetoo: in my case, i also soldered the diode backwards. after pulling the throttle, the motor ran slowly then the diode started to burn up and crack open. after removing the diode, everything worked fine. i dont think this will damage the motor and esc.

Geetoo

iTrader: (1)

Marvi/Doraemon: Kasi when I was soldering it, may dumaan na magandang chicks Yun ang palusot ko. Pero kung uulitin ko eh dapat dumaan ulit yun chick. Pero sige I will check it out. Thanks!