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Hey everyone. I thought we'd all throw in some electrical/computer/audio equations here and throw it into the FAQ.
Ohm's Law:
Ohms = Volts / Amps
Amps = Volts / Ohms
Volts = Ohms * Amps
Watts Law (?)
Watts = Volts * Amps
Volts = Watts / Amps
Amps = Watts / Volts
Can anyone throw the battery time thing up? liek fi your system draws 3 amps, it takes 5 hours to kill battery? thanks.
From here: http://www.1st-optima-batteries.com/amp_hours.asp
Two standard ratings are used to measure a battery's storage capacity.
Amp Hours
The Amp Hour rating tells you how much amperage is available when discharged evenly over a 20 hour period. The amp hour rating is cumulative, so in order to know how many constant amps the battery will output for 20 hours, you have to divide the amp hour rating by 20. Example: If a battery has an amp hour rating of 75, dividing by 20 = 3.75. Such a battery can carry a 3.75 amp load for 20 hours before dropping to 10.5 volts. (10.5 volts is the fully discharged level, at which point the battery needs to be recharged.) A battery with an amp hour rating of 55 will carry a 2.75 amp load for 20 hours before dropping to 10.5 volts.
Reserve Minutes
Reserve minutes is the number of minutes a battery will carry a 25 amp load before dropping to 10.5 volts. (10.5 volts is the fully discharged level, at which point the battery needs to be recharged.)