Fusing: Selective Tripping vs Wire Rating

[neo_styles 10+ year member]

Hi guys, just want to confirm I'm not going overkill on diagramming my install this month. Project will be utilizing the trunk-mounted battery on stock electrical (Big 3 done later when I can order enough Knu), a Rockford P8004 and PG Octane-R 5.0:4. Both 4-channels will be running bridged 2-channel at 4 ohms (comes out to a spec'd 400x2 on the P8004 and 150x2 on the PG).

Point of this thread: the Navy taught me about "selective tripping," which is basically a fancy way of saying you have different trip points between each load and its source that go up the closer you get to the source. As I see it in the ca world, I could fuse each side of a distro to 10% over the fusing on each amp and the inline fuse for 10% over the combined fusing of the distro.

Am I overthinking this? Should I just fuse inline to the spec rating of the wire itself?

I'm all eyes/ears...

Click to read more...

 

[neo_styles 10+ year member]

I realized I probably made this more confusing than necessary, so let me use my example.

Total fusing on PG: 2x25A=50A

Total fusing on RF: 3x40A=120A

Fuse rating of wire: 300A

Option 1:

Fused distro with 60A fuse and 120A fuse

Inline fused with 200A

OR

Option 2:

Same on distro

Inline fused with 300A

 

[gckless 5,000+ posts]

Probably just keep things simple man. But it's your system, it's your call.

 

[neo_styles 10+ year member]

So I read what you said and then I saw benbens comment in your sig...give me five min to bring my iq back up to normal again so I can reprocess...

Jk thanks for the info. Thought I was overdoing it

 

[gckless 5,000+ posts]

So I read what you said and then I saw benbens comment in your sig...give me five min to bring my iq back up to normal again so I can reprocess...
Jk thanks for the info. Thought I was overdoing it

Yeah, it's pretty unintelligible. I'm also upset the latest thread got deleted.

 

[keep_hope_alive Premium Member]

selective coordination is not something we worry about in car audio. we just focus on the two main purposes of fuses: overcurrent protection which protects the wire and short circuit protection which protects the battery.

size the battery fuse for the wire and it serves both purposes. from there, you don't need any other fuses than what is in the amp. the distro can be non-fused if you'd like since the amp fuses provide over current protection for the wire feeding it.

 

[neo_styles 10+ year member]

Thanks for that, man. Looks like I can save myself a decent chunk of change on what I have left to order, then.