300 Amp Fuse?

If you want me to be honest and give you more information then you need to know, it depends on the manufacturer. Not all fuses rated for the same amperage will perform the same.

I wouldn't be so concerned with how much current the fuse will handle. Worry more about what size is needed to protect your wiring/equipment.

 
It all depends on many factors. There is no way to answer such a vague question.

But, to ballpark it, you can assume a few things and give you a round-about answer.

A 300A fuse will not blow until about 600A is passed through it for a second or so. So in theory, you could pass almost 600A for a split second. Let's assume that you have a strong 12V system. Your voltage does not drop from 15.0V even under load. (Not likely, but for argument sakes, let's just assume)

600A x 15V = 9000W x 90% (best case amp efficiency) = 8100W max power

Now how likely are you looking to get a less than one second burp? How likely is it that your voltage will not drop? How likely is it that your amp efficiency is not going to drop under heavy loads? What is the possibility of the perfect storm?

None.

 
How many watts can this fuse be able to take before going out?



Thanks,
Roughly 4200 Watts. Power = Voltage x Current

Assume Voltage is 14V or close, so 14V x 300A = 4200W RMS

This assumes a constant draw. In a quick pulse, it could do more before it blew

 
I got my fuses from Knuconceptz. I will be using a Sundown 3000D at 1/2 Ohm with a MLA module so the voltage will be roughly 15.3 Volts.
Correction, your voltage will be 15.3V BEFORE your amp is pushing power //content.invisioncic.com/y282845/emoticons/fyi.gif.9f1f679348da7204ce960cfc74bca8e0.gif

Depending on the max output of your alt, it will surely dip well below that 15.3V //content.invisioncic.com/y282845/emoticons/crap.gif.7f4dd41e3e9b23fbd170a1ee6f65cecc.gif

 
Correction, your voltage will be 15.3V BEFORE your amp is pushing power //content.invisioncic.com/y282845/emoticons/fyi.gif.9f1f679348da7204ce960cfc74bca8e0.gif
Depending on the max output of your alt, it will surely dip well below that 15.3V //content.invisioncic.com/y282845/emoticons/crap.gif.7f4dd41e3e9b23fbd170a1ee6f65cecc.gif

I know that but I just wanna know if the fuse will blow if I ran 4500+ Watts?

 
you'll be fine.

and if it does blow, so what. get a bigger one.

fuses are relatively cheap in the car audio world.

as long as your not using a super long run of 1/0 (under ~25 feet) you could PROBABLY use a 400 amp fuse in there and still be safe although i have never personally used that large of a fuse with 1/0 before.

 
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