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caps: help or hinder?

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Old Nov 24, 2004 | 02:26 AM
  #11  
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Originally posted by Team Obsession:
</font><blockquote>quote:</font><hr />Originally posted by Newb:
</font><blockquote>quote:</font><hr />Originally posted by Coffeyman:
i kinda figured that much about caps...
but does anyone have any idea about how much capacitance (in farads) you would need to run a few thousand watts uninterrupted?
i'm just curious b/c in street a/b you're only allowed 1 cap and i wanted to know if they make one single cap big enough to accomodate a street competition system....
1 Farad of capacitance, not one cap. those 50-100 farad mega caps are no bueno. </font>[/QUOTE]cap=capacitor (is what we're saying) </font>[/QUOTE]Ok, he said "in street a/b you're only allowed 1 cap and i wanted to know if they make one single cap big enough to accomodate a street competition system.... ", which is wrong. There is no limit on the physical number of caps in street a/b, there is a limit on capacitance.

Makes me wonder how long it will take the manufacturers to come out with "cheater" caps [img]graemlins/freak.gif[/img]
Old Nov 24, 2004 | 10:02 AM
  #12  
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1 farad of capacitance can be gotten with 4 1 farad caps, wire 2 sets of 2 in series, and the 2 sets in parallel, that's 1 farad of total capacitance, but is 4 caps, you can do the same thing with 9, 16, 25, 36 caps, etc.
Old Nov 24, 2004 | 10:11 AM
  #13  
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Actually they do make "caps" with very high storage capacities already. Exstatic or BatCap makes capacitors that have up to 400 farads of energy stored in them. The magic word that everyone has been stumbling around is the word Farad. Farad is used to describe a measure of energy. In street A/B I believe that you are allowed to have 1 or 2 "farads" of capacitence, the number of "capacitors is irrelevant.
Now I am not to sure of the street rules but I believe that is the way it is. If I am wrong I am sorry. Oh and caps do hinder SPL, they discharge faster then the sensor can read and your electrical system is then continuosly playing catch up. This was tested not assumed.
Old Nov 24, 2004 | 10:22 AM
  #14  
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yes he's right, we actually did test that

if the cap could handle the voltage and current without hindering it, it would create a more stable, uninterrupted singal
actually a cap would do none of that. and if u have interrupted signal in your power cable i think u need to worry about MUCH bigger problems than just getting a cap.

[ November 24, 2004, 11:26 AM: Message edited by: Father Yuli ]
Old Nov 24, 2004 | 11:05 AM
  #15  
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Actually Farads is not a measure of energy. It is simply a ratio of the charge existing on the plates and the voltage at which the charge exists. (C=Q/V) It has units of coulombs per volt.
Energy in the capacitor is equal to (1/2)CV^2, so the voltage has more to do with the energy stored. By using transformers and capacitors in parallel, (Capacitance sums in parallel) you could actually do a lot with one farad, but the unit would have to be large to prevent the voltage ont he plates from arcing across rather than transferring through the electric field in the dielectric. I am sure someone in the future will try to do this, and they will have to change the rule so that only 12 volts is allowed across the plates.
Old Nov 24, 2004 | 11:13 AM
  #16  
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Originally posted by seege:
Actually Farads is not a measure of energy. It is simply a ratio of the charge existing on the plates and the voltage at which the charge exists. (C=Q/V) It has units of coulombs per volt.
Energy in the capacitor is equal to (1/2)CV^2, so the voltage has more to do with the energy stored. By using transformers and capacitors in parallel, (Capacitance sums in parallel) you could actually do a lot with one farad, but the unit would have to be large to prevent the voltage ont he plates from arcing across rather than transferring through the electric field in the dielectric. I am sure someone in the future will try to do this, and they will have to change the rule so that only 12 volts is allowed across the plates.
so josh... i thnk we have a project to do this coming spring? [img]graemlins/thumb.gif[/img]

livin Loud
Old Nov 24, 2004 | 12:02 PM
  #17  
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I have actually considering making a cap capable of storing large amounts of energy, but I guess it would be considered directly trying to find a loophole in the rules. Right now 1 farad stores about 72 joules of energy, so it can produced 72 watts for 1 second or 720 watts for .1 seconds. (.5*1 farad*12 volts^2)
Bump that up to 200 volts through the cap, which would actually fit in a vehicle, and you have 20000 joules. Granted, transformer loss would reduce that number, but that is enough to supply 10000 watts for two seconds off af one farad.
Old Nov 24, 2004 | 12:08 PM
  #18  
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hheeehehe

i guess now it has to be commercially available?


livin loud
Old Nov 24, 2004 | 12:21 PM
  #19  
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it already is, u can buy such units from me
Old Nov 24, 2004 | 12:27 PM
  #20  
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woooooohhhhooooooooooo!!!!!!!!

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