CarAudioAddict 10+ year member
What did I do now?
To find out the amperage draw on an amplifier takes its output power (RMS for average draw and total for max draw) and devide by 12. This will give a reading assuming the amp was 100% efficient. Now you have to consider that class AB amps are only about 60% efficient and class Dare about 80%. Divide the number of amps you got from the last equation by the efficiency of the amp and you should end up with a fairly accurate number.
so, amperage draw equation:
( output power / 12 ) / effeciency = amperage draw
example using a 1000 wattt class AB amplifier @ 60% efficiency
( 1000 / 12 ) / 60% = ( 83.333 ) / 60% = 138.9 Amps
so, amperage draw equation:
( output power / 12 ) / effeciency = amperage draw
example using a 1000 wattt class AB amplifier @ 60% efficiency
( 1000 / 12 ) / 60% = ( 83.333 ) / 60% = 138.9 Amps