Fuse Size

[PILOT 04 10+ year member]

I have a question concerning fuse sizes. I will be running Alpine MRP-F240 and an Alpine MRP-T220 amp in my setup. How do I calculate the size fuse I will need for the battery lead fuse holder and the distro block in the back? I want to make sure that I fuse this right so I don’t fry my equipment or car. Thanks in advance for our assistance……….

Click to read more...

 

[dkguitarist 5,000+ posts]

To approximate fuse size you want to use the voltage of the power supply (12-14) not the voltage out of the amp's speaker output.

power/voltage=amperage

also the fuse by the battery is the combined total of both fuses for the amps

 

[RandyJ 10+ year member]

if it max you're pulling 200A, then put a 200A at the battery, then at the dblock, fuse each seperate line for how much that amp will be pulling. make sur eto take into consideration wire size though, you don't want to split into 8awg at the block and fuse for 150A, ya know?

 

[nVRuckus 5,000+ posts]

To approximate fuse size you want to use the voltage of the power supply (12-14) not the voltage out of the amp's speaker output.power/voltage=amperage

also the fuse by the battery is the combined total of both fuses for the amps

I thought it was divide the watts by 12 and you'll have the amperage

 

[dkguitarist 5,000+ posts]

I thought it was divide the watts by 12 and you'll have the amperage

that's what i said. just in different words. //content.invisioncic.com/y282845/emoticons/rolleyes.gif.c1fef805e9d1464d377451cd5bc18bfb.gif

*edit* i did say power but i meant watts. i kno what i was saying but someone else's interpretation may be different than mine. sorry for the confusion.

 

[knukonceptz 10+ year member]

Watts = Volts x Amps but the easiest way is just add up each fuse in the system, that is the max you can draw and would be the main fuse size at the battery ( you can fuse the cable for its max handling as well, but is not required) For more info

http://www.knukonceptz.com/assets/pdf/PowerWireSpec.pdf

 

[PILOT 04 10+ year member]

Watts = Volts x Amps but the easiest way is just add up each fuse in the system, that is the max you can draw and would be the main fuse size at the battery ( you can fuse the cable for its max handling as well, but is not required) For more info
http://www.knukonceptz.com/assets/pdf/PowerWireSpec.pdf

Thanks Knu, I just ordered some equipment (distro block, fused distro block, terminal ends, etc) from your website last night. Forgot about fuses and that is why this post came up. I wish that ordered my RCA cables from you because the company I ordered mine through is taking forever to send them to me. I figure your an hour away so you will get my stuff to me quick //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[knukonceptz 10+ year member]

Shoot us an email with the order number and we can add the fuses with the order, it has not left here yet.

 

[johnecon2001 5,000+ posts]

Usually you fuse to the max amperage of the wire. If you have some 8awg and you're drawing 200a of power.. you obviously don't want to fuse to 200a on a piece of wire only rated at 80a.

You need to verify that the wire you are running can handle the amount of power you want to pull through it. After you do that, fuse to the max safe capacity of the wire.

Normal fusing is as follows.

1/0awg max is 350a

2awg max is 220a

4awg max is 150a

8awg max is 80a