Originally Posted by murphy_smith
My run from batteries to amp is less than 4 feet with 1/0 cable.
On average the Arc Audio KS amps are 81% efficient at 4 ohms and 76% efficient at 2 ohms.
Based on a correct calculations firguring in efficiency, my 300.4 is pulling 40 amps, my 300.2 is pulling around 65 amps and my 500.1 is pulling 55 amps. Keep in my that these numbers are based on 13.3 volts and respective efficency numbers listed above. So in total I am pulling 160 amps, even if you drop to 12 volts it is no where near the 240 you refrenced earlier.
In years past I have run a 150 amps circuit breaker between the batteries and all three amps, never once tripped it. I think if I was pulling 240 amps, that it would trip at least once???
Anyways, I will go with a circuit breaker.
My bad, but the 240 was your number, not mine. If I had known this was a quiz, I would have studied before posting
Ok, lets clarify. It very common to fuse based on the amp's potential current draw, which is exactly what the amp manufacturer did. You gave us that potential draw by stating the 3 amps had 8 30A fuses between them for a total of 240A's. So it's perfectly acceptable to fuse up to that potential (max) current draw. Fusing based on efficiency and current draw at normal listen levels is on the conservative side of safe, and may lead to tripped breakers or blown fuses if the system is pushed hard. $.02
Sounds like you got it under control and already knew the answer, so by all means, proceed with the fuse that you feel comfortable with.