Fuse Plan - Can I do it this way?

[plectrudis]

I've been studying up on wiring, and I could use some help understanding how to decide which components to group together on a fuse.

Here's how it makes intuitive sense to me to do it:



All the stuff that's physically close together in the trailer (the passengers'-side porch light and reading light, for example, or the drivers'-side USB and 12v outlets) share a fuse. This way, they can share a wire, which would presumably provide the most efficient use of wire.

But all the wiring diagrams I'm finding don't do it that way. They group by type: all reading lights together, all porch lights together, all 12v outlets together, and so on. For example, here's an outtake from my current favorite wiring diagram (http://chucksteardropbuild.blogspot.com/2012/07/electrical-diagram.html), and it uses this other approach.



There has to be a reason--why is it better to do it this way? Or does it matter?

Thanks for the help!

[pchast]

I find it best to have lights on more than one circuit in the rare
occasion that a fuse blows.

[plectrudis]

Excellent point! So you don't see any red flags with this arrangement?

[tony.latham]

Excellent point! So you don't see any red flags with this arrangement?

I don't see any problems other than you are going to have to make a junction at some point for those circuits that feed more than one device.

If you went with a fuse box with plenty of fuses like this, each would have it's own fuse and you wouldn't have to solder up and protect your junctions.
https://www.amazon.com/Blue-Systems-Bla ... B01BXTXV1Q (12 circuit with negative strips and cover)

Tony

[plectrudis]

That actually brings me to my second question, Tony: I like the recommendations for the Progressive Dynamics 4045. If I get that, will it serve as the fuse box, or will I also need a separate fuse box?

https://www.amazon.com/Progressive-Dynamics-PD4045KV-Mighty-Distribution/dp/B002XRU6FM/ref=sr_1_1?s=automotive&ie=UTF8&qid=1468093767&sr=1-1&keywords=Progressive+Dynamics+Mighty+Mini+4045

[KCStudly]

I would keep the fan on its own circuit separate from lighting and charger/electronic device circuits. Motors have start up current demands and can cause funny feedback issues in certain circumstances. Probably won't be an issue but if I had a choice I would keep them separate.

[tony.latham]

That actually brings me to my second question, Tony: I like the recommendations for the Progressive Dynamics 4045. If I get that, will it serve as the fuse box, or will I also need a separate fuse box?

https://www.amazon.com/Progressive-Dynamics-PD4045KV-Mighty-Distribution/dp/B002XRU6FM/ref=sr_1_1?s=automotive&ie=UTF8&qid=1468093767&sr=1-1&keywords=Progressive+Dynamics+Mighty+Mini+4045

Now you're way over my pay grade!

I'm a 12V guy. (But I think those PD4045 have all your DC circuits protected. Don't know for sure.)

Tony

[m.colley]

That actually brings me to my second question, Tony: I like the recommendations for the Progressive Dynamics 4045. If I get that, will it serve as the fuse box, or will I also need a separate fuse box?

https://www.amazon.com/Progressive-Dynamics-PD4045KV-Mighty-Distribution/dp/B002XRU6FM/ref=sr_1_1?s=automotive&ie=UTF8&qid=1468093767&sr=1-1&keywords=Progressive+Dynamics+Mighty+Mini+4045

It will serve as a 12V fuse block as well as 120V breaker panel. It will also act as a 3 stage charger for your battery when plugged in to shore power.

Martin

[H.A.]

Good practise is to separate types of lighting to different fuses.
But these fuses may protect other non-lighting circuits.
Betterment of safety the point being. A single fuse blowing leaves alternate lighting circuits live. Especially so for interior lighting.
Examples, If primary interior lighting fails, One could switch on a reading lamp & avoid being totally in the dark.
Or depending on ones layout & use of luminaires, Splitting the interior to left & right side circuits. One circuit failure leaves the other side operational.
That example of Galley lighting shared with 12Vgalley sockets is poor practise.
An overload of a galley socket (which is very plausible), may unexpectedly put the galley dark.


Much like cars have lighting on different circuits to prevent a total blackout in the event one circuit fails.
Build a camper to similar regards.

[Shadow Catcher]

Plan on more than you think you need Our PD4045 has 14 12v fuses and I am using them all. charging cell phones, lap top, iPad... they all add up.

[plectrudis]

Great information--thanks, all!

KC, good point about the fan--I can definitely do that.

Martin, thanks for the clarification on the PD4045--that's good news. Does it also serve as a ground block, or will I need a separate one of those?

H.A., if I've understood you correctly, my plan to separate the cabin interior lights by drivers' side versus passengers' side is fine; I just need to adjust my plan for the galley. Your point about tripping the 12v outlet makes sense--I'll fix that.

ShadowCatcher, I suspect you're right. This was supposed to be a simple electrical system to accommodate my newness to working with electricity. But when I draw in the wiring paths on my trailer, it looks like rainbow-colored spaghetti. Keeping It Simple Stupid is harder than it sounds.

[m.colley]

Great information--thanks, all!
Martin, thanks for the clarification on the PD4045--that's good news. Does it also serve as a ground block, or will I need a separate one of those?

Yes you'll need a ground block. I ran a doubled 10 gauge ground (its what I had on hand) from the battery to ground block and tied my negatives back to the ground block.


Martin

[plectrudis]

Thanks, Martin