[Electrical] Current consumption

[portista]

CTScott,
First of all let me thank you and congratulate you because you were the only person in many of the internet forums that I access that was capable of giving me a concrete answer to a problem!! Cheers mate!

So let me see if I got this straight. I suppose you used a multimeter between the positive side of the battery and the main cable that goes to there, correct?

The measures that you took state that at idling with everything shut down you have around 23A of current to spare and with the lights and so on you have about 7Amps of current to spare correct? So 7*14.4V (I suppose that the alternator provides this voltage) gives us a total of 100W... This doesn't make it even for a subwoofer , am I correct?

Also I am getting worried since your car is a p2 yaris, whose alternator has a capacity of providing 90A instead of the 70Amps from the p1, am I correct?

Greetings

[CTScott]

Originally Posted by portista

CTScott,
First of all let me thank you and congratulate you because you were the only person in many of the internet forums that I access that was capable of giving me a concrete answer to a problem!! Cheers mate!

So let me see if I got this straight. I suppose you used a multimeter between the positive side of the battery and the main cable that goes to there, correct?

The measures that you took state that at idling with everything shut down you have around 23A of current to spare and with the lights and so on you have about 7Amps of current to spare correct? So 7*14.4V (I suppose that the alternator provides this voltage) gives us a total of 100W... This doesn't make it even for a subwoofer , am I correct?

Also I am getting worried since your car is a p2 yaris, whose alternator has a capacity of providing 90A instead of the 70Amps from the p1, am I correct?

Greetings

Our P2 Yaris has a 70A alternator as well. You are correct on ~100 Watts when everything else is running, but that should not be the case most of the time, so the 23 A (331 W) or more would be your more your typical availability. Remember that I measured these at idle, so there would be more surplus with the car in motion. Also, your 1000 W amplifier is only drawing that much while your ears are bleeding, so the 100 - 300 W supply would probably be more than sufficient for normal use. During the occasional blasting of music you would be drawing from the battery, as the alternator would not be able to keep up.