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Old 07-01-2008, 02:49 AM   #1
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Default Q about the CAP mod for COPS

So I toar apart a old amp, found a 22,000 uf capiactor. I know thats double the suggested, is that too much?
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Old 07-01-2008, 04:15 AM   #2
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Originally Posted by cardriverx View Post
So I tore apart a old amp, found a 22,000 uf capacitor. I know that's double the suggested, but is it too much?
Not trying to be a grammar ****, but fixed it for people that will look
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Old 07-01-2008, 10:09 AM   #3
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Nothing is ever too much, use it.
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Old 07-01-2008, 10:18 AM   #4
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You'll have the ability to store more energy...I don't see nuttin' wrong with that.... make certain the polarity is correct.
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Old 07-01-2008, 10:47 AM   #5
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the voltage rating needs to be high enough. probably at least 20VDC for a reasonable factor of safety. higher is fine.
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Old 07-01-2008, 12:45 PM   #6
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the voltage rating needs to be high enough. probably at least 20VDC for a reasonable factor of safety. higher is fine.
Its rated for 25V, its a monster haha. Alright cool, I get it so the cops an just take energy from the capiactior as needed, so there is no too big. cool.
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Old 07-01-2008, 12:48 PM   #7
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Yup. When using a capacitor as a voltage stabilizer for a heavy load at the end of a long cable run, bigger is always better, right up to the point where it blows a fuse at turn-on.

As Y8s pointed out however, electrolytic capacitors have two principle ratings, voltage and capacitance, which for a given physical dimension tend to vary inversely to one another. In other words, a cap rated for 10,000uf at 10 volts and a cap rated for 4,700uf at 20 volts will tend to be about the same size.

So, if your 22,000uf cap is rated at a sufficiently high voltage, then it will be "better" than a 10,000uf cap of the same voltage rating. The guys with the big subwoofers in their car routinely run caps of 1 farad (1,000,000uf) and bigger.
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Old 07-01-2008, 01:01 PM   #8
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Yeah I noticed about the size thing, I opened two powersupplys and each had 2 big capiactiors, but they were around 3000 uf and rated at 200 volts hah. Those capiacitors for subwoofers are huge.

Joe what do you do for a living? You know a good amount about electronics, thanks for all the help.


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Originally Posted by Joe Perez View Post
Yup. When using a capacitor as a voltage stabilizer for a heavy load at the end of a long cable run, bigger is always better, right up to the point where it blows a fuse at turn-on.

As Y8s pointed out however, electrolytic capacitors have two principle ratings, voltage and capacitance, which for a given physical dimension tend to vary inversely to one another. In other words, a cap rated for 10,000uf at 10 volts and a cap rated for 4,700uf at 20 volts will tend to be about the same size.

So, if your 22,000uf cap is rated at a sufficiently high voltage, then it will be "better" than a 10,000uf cap of the same voltage rating. The guys with the big subwoofers in their car routinely run caps of 1 farad (1,000,000uf) and bigger.
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