Quote:
Originally Posted by 3rk5
I have a sub laying around and was thinking of installing it into my V50 which has the Premium sound system, but no subwoofer. I've read that there is still a 15A power line running to the back of the car for the factory sub even though I don't have that option. Is it safe to use that wire for my aftermarket amp and sub? It's a really weak amplifier actually, RMS is only 75W (max 250W).
|
I think P(W) = V*I(amps) So a 15Amp load at 14.4 volts, will be a power in watts of 216. So technically has a max power handling of 216 watts on a 15Amp circuit. This means 250watt PMPO amp could well blow a fuse or burn out the power wire.
250/14.4 = 17.3 Amps.
In reality, it probably wont pull a sustained current of above 15amps, but I'd not risk it for the hassle it could cause.
Edit. I did some checking, and online resources suggest using the total RMS wattage. So if its 75W total on one channel, use this figure. But you have to accommodate the amps efficiency. assume .50 (its probably more efficient than this. so (75/14.4)/0.50= 10.4 amps. So you might get away with it after all.