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any ESC expert..

Started by gunnu, February 27, 2015, 10:20:41 PM

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gunnu

hello.
i have 30A Simonk esc (from quadkopters) and it has 25v 470μf capacitor attached to it... and Unfortunately i lost it..
so can i use 50V 1000μf capacitor instead of that...?? if u use than does it affect/harm ESC and motor in in any way??
:help: :help:

regards

Himadri Roy

Such capacitors are used to supplement power to the MCU in case of a power glitch so to prevent reset of the MCU(can cause reset of ESC stopping the motor thus crashing the quads)...so it can be used!
For once you have tasted flight you will walk the earth with eyes skywards for there you have been and there you will long to return
- Leonardo Da Vinci

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gunnu

if i use this capacitor than it will not harm motor and esc to ( in any way ) .correct na??

Himadri Roy

It shouldn't harm the esc or motor as the capacitor acts as a power bank kind of thing by using the 1000 uF cap you are increasing the the capacity of the cap to hold more charge and as you are using 50v rated cap so the voltage is higher than the input voltage so the capacitior wont burst! :hatsoff:
For once you have tasted flight you will walk the earth with eyes skywards for there you have been and there you will long to return
- Leonardo Da Vinci

https://www.youtube.com/himadrifpv

gunnu


Himadri Roy

Anytime ;D :hatsoff: but as a precautionary measure wait till tomorrow so that few more people can voice there opinion....
For once you have tasted flight you will walk the earth with eyes skywards for there you have been and there you will long to return
- Leonardo Da Vinci

https://www.youtube.com/himadrifpv

gunnu


Himadri Roy

Did you burn your capacitor or it tore off?
For once you have tasted flight you will walk the earth with eyes skywards for there you have been and there you will long to return
- Leonardo Da Vinci

https://www.youtube.com/himadrifpv

gunnu

actually soldering wires to esc.. (making it compact for my quad) and desolder capacitor. and forget where i put capacitor... :banghead:
thats why thinking to put large capacitor ( coz didn't find 25v 470mfd capacitor locally)

regards

Himadri Roy

But try to get a 470 uF(recommmended) if under crisis use the 1000 uF...i came across this reply froma vid in youtube about caps
"Depending on the application of the capacitor, changing the capacitance (the value of the capacitor) may change the quantity of energy available in your circuit, the types of signals in the circuit, the recharge time, etc. It may even blow your capacitor if the rating of the capacitance is too low.

In electronics there's something called a "gain", which says how much voltage you lose or gain depending on the values of the component. There is also something called "frequency response", which is how circuits reacts to signals (voltages and currents) of different frequencies (oscillations). These factors are heavily depended on the values of the components.

Yes, capacitors that are in microferrets may SEEM small, but many circuits are built in such a way that at the end you're dealing with much bigger numbers (1000~0.001). So the values of the capacitors become much more significant when they are much bigger. The value that I'm talking about is called the time constant.

The time constant of an RC circuit is the value of the resistor times the value of the capacitance ( RC ). The time constant of a circuit is related to many things such as the frequency response (how a circuit reacts to voltages/currents of different frequencies/oscillations), the gain (how much bigger or small the voltage/cirrent becomes), the recharge time (how fast the capacitor fills up.

The reason I said "no" is because you're dealing with a change in the factor of about 200. This may not seem significant because microferrets are small, but when you find the time constant of the circuit you will see that this value turns out to be much smaller than the original value. This will affect the frequency response and the gain of a circuit. So if it were a radio, you might suddenly start picking up a signal from another station because the frequency response was changed, and you might not be able to hear it so well because the gain was dropped.

In short, just because the value of the capacitance is small doesn't mean that it doesn't matter. There is a change in a factor of about 200, and you better believe that will affect your circuit. "
For once you have tasted flight you will walk the earth with eyes skywards for there you have been and there you will long to return
- Leonardo Da Vinci

https://www.youtube.com/himadrifpv

gunnu

ok tomorrow ill try to find 25v 470uf capacitor in my local market again..

Himadri Roy

any voltage rating will do not just 25v but make sure its >= 25v
For once you have tasted flight you will walk the earth with eyes skywards for there you have been and there you will long to return
- Leonardo Da Vinci

https://www.youtube.com/himadrifpv

gunnu

i think i have 50V 470uf capacitor..

shreeyak

The voltage rating won't affect it. More means it can handle more voltage, is all.
As for the value, see the circuit if it's connected to the plus and minus of the voltage supply or the voltage regulator. If so, it's as posted I the first reply. To filter out noise in power supply.

AshwinRwt

IMO its just a decoupling capacitor, you can use anything you want, it'll just get charged when you power it on and give out power if there is a power glitch. There is no rc time constant involved in here, its just like a backup. There shouldn't be any problem. In rc car esc's people swap out caps on the esc with higher capacity, so they can get extra current when needed.

And if you're confused where the leads go, its simple, the cap is wired in parallel, which means -ve to -ve, and +ve to +ve. So the longer lead to the red wire (where the battery connects) and the shorter to the black. Polarity is important in electrolytic caps (the one in context) otherwise you'll be celebrating diwali a bit earlier.