Electrical wiring/grounding, fuse block and ARB compressor

I've seen a couple different write-ups on electrical and have a question. I bought the 12 circuit Blue Fox fuse block last night. I checked out 4X4Runner's photo and numerous others on the web. I'm making an Excel spreadsheet of the accessories I'm getting with amps, volts, etc.

I'm confused on setting up switched circuits vs. full time circuits but for right now I'm only adding a light bar and pods so I'm pretty sure I'll realize to turn them off. I will try switched circuits later if the need or want arises.

My confusion is on grounding. I'm a civil engineer and took electrical classes in college but car audio was always a pain with buzzing speakers, grounding amps, crossed power and RCA's, etc.

So here's the question!! I understand that with light bars, etc. you can either ground at the fuse block (which I will do for now) because my wiring is up front OR if you have lights in the back, you run the power from the fuse block to the lights BUT you can ground the lights AT the back? I'm confused because if you have relays for the switches etc. in the engine compartment and switches on the panel, why not run the ground back to the front fuse block?

Also, I want the ARB compressor at sometime in the near future. I see it draws 56 amps at max air flow. Does it somehow get wired to 2-30 amp circuits to be covered for 60 amps or does it actually get wired to the battery.

I'm just trying to plan out my build to make sure I do everything correctly, neatly and safely.

Thanks for any input.

Shane

 

Gotcha, so instead of wiring the compressor to the new fuse block, it's the only "extra" thing you have wired to the battery. That makes sense. Everything else running through the fuse block for me will be low amps.