Show off your aux fuse panels.

Fuse for the wire - it's ok to be under based on actual need but never use a higher rated fuse than the wire will support.

More than likely, you're using bundled wire so be sure to use that as a reference.




So, to answer your question... depends on what size wire you use for your accessories

Reference this link to determine that... https://www.bluesea.com/resources/1437


What gauge wire do you need to use for accessories? Divide the watts of a given item by the total number of volts available to calculate amperage draw.

Example: You have two 20W LED pods you want to use for ditch lights.
20w*2/12v= 3.333 (amps)

Now that you have your amp draw, use the following calculator to determine what gauge wire to use for your run based on length of run, total amp draw.

https://www.wirebarn.com/Wire-Calculator-_ep_41.html
http://circuitwizard.bluesea.com/

again, once your wire gauge has been chosen, you can then determine your fuse requirements.

at least that is how I understand it.

 

You don't need both a 100A breaker and a 100A fuse for the panel, either one will do but the breaker is more convenient. Match each fuse to the lowest rated item in that circuit. You can have more than 100A worth of fuses in the panel but no more than 30A on any individual circuit and don't use more than 100A worth of devices at a time. That's a boatload by the way being what used to be the common service for an entire house.

 

How do you like that box? I like that it's waterproof compared to the typical Blue Seas fuse blocks. How do you deal with negative wires? Do you still need a negative bus bar? I don't see a where you install positive wires. Can you show any more pictures of how you installed it?

 

Hi,
There is not a neutral bar on this box, it is a compact relay/fuse box for all the hot leads. I bundled the negatives with a large crimped clamp that I shrink wrapped and splice taped. If you need an imbedded bar there is not enough space inside this neat box.

 

Thanks that's what I thought. I think I'm going to attach

$20 Bud Industries CU-3285 Plastic Style A Utility Box 8.25" L x 5.15" W x 3.12" H, Black

this box to my powertray and then mount my relays and Blue Sea 12 fuse block inside of that to keep everything watertight.

 

Good approach. I had a similar for close to three years before I felt confident I wasn’t adding too many more under hood circuits.
Before:

During:

After:

 

I've got a 100A breaker and blue sea fuse block. When I wire it all up and the ground is going from the block to the body of the truck (where everyone else put it under the hood) will that eliminate me from having to find a ground for accessories going forward? On the block there's a + and - for each fuse so I'm assuming this is the case.

 

You need to account for all the current that any ground return to battery will be. If all your returns from the new block are “also” passing through the factory body to battery negative lead, you may want to increase the size of that cable. I actually run straight from the battery to my aux fuse panels.

 

Worked up an Aux Fuse box for the bed of the truck to support rack lighting on the cap, cap LED strips and any other options I may move to in the future.

Have a

$48 Bussmann (BP/CB185-100) 100 Amp Circuit Breaker

100A breaker coming off the battery (Northstar AGM 24F) and from there Positive and Negative 4 AWG welding cable runs along the frame rail to the bed.
Used a

Gratury Junction Box, Hinged Cover IP65 Waterproof Plastic Enclosure for Electrical Project Includes Internal Mounting Panel 290×190×140mm (11.4"×7.5"×5.5")

DIY Enclosure to mount the

$30 Blue Sea Systems 5025 ST Blade Fuse Block 6 Circuit with Ground and Cover

Blue Sea block along with the relays and switch panel.

*NOTE* The DIY Enclosure is 'ok' but the hinge on it sucks. Picked up a

$32 QILIPSU Waterproof Outdoor Junction Box, IP67 ABS Plastic Electrical Enclosure with Mounting Plate, Wall Brackets, Weatherproof Hinged Grey Cover for Projects (11.2"x7.7"x5.1")

different version but just have not found the time to swap it in.


Also added USB 3.0 Quick Charge ports, a 12v Power Port and a

$40 Blue Sea Systems 1733 Mini OLED DC Voltmeter, Yellow

Blue Sea Voltmeter. Those 3 are tied to a single switch on the panel.

All switches ordered from @OTRATTW OTRATTW.
RTMR Panel by @paranoid56 here.

The trigger wires for the rack lighting run from the cab switches to the switches in the Aux Fuse box. So if a rack lighting circuit is powered, both switches will illuminate. Not that I'd forget they were on but kind of a 'where's your brain?' fail-safe

Many thanks to @bagleboy for his guidance in working through the logistics of setting this up along with the bussmann RTMR in the engine bay. Really appreciate all the help

 

So what does everybody use to feed wires thru the hole to the cab? I’ve already used the hole for rubber grommet and I can’t fit anything in there after only ditch lights installed to switch. Also I can’t seem to get my wires to go thru the bigger hole there from factory where several of the wires go thru.

 

You can always try this tool:

OTC 4462-5 Wire Loom Grommet Tool

https://www.amazon.com/dp/B00KIKYVU2/ref=psdc_15707531_t2_B073WZCL8Q

 

Was going to suggest the same type of tool. I wasn't expecting much when I ordered it but sure works better than a coat hangar! I went with this cheap generic one -

$12 Performance Tool W2935 Stainless Steel Wire Insertion Tool - Piercing for 1/4" Wiring Hole

https://smile.amazon.com/Performance-Tool-W2935-Insertion-Piercing/dp/B073WZCL8Q

 

Got my aux box running and covered with my kc ditch lights and rigid led bar mounted and hooked up

 

I wish I had this for my bumper light and ditch light installs. Going to get one for future projects

 

Also these!

$9 Wire Loom Cable Insertion Tool for 3/8" to 1/2" - Model CM08

https://smile.amazon.com/gp/product/B005DTKNZU

$8 Yellow Loom Tool Kit - Cable Insertion for Bundles from 1/4" to 1" (1 Small Tool + 1 Large Tool)

https://smile.amazon.com/gp/product/B06ZZGX5VL

I used the yellow ones the most but the orange is much better quality. Talk about a time saver (and finger saver)!

 

Sold!

 

Nice set up, say a question, how long is your wiring run from the aft sub panel to the fridge outlet? I am planning to get a Dometic CFX 65w fridge and am thinking about running at least 10awg about a max of 10’-piling up the parts while I’m down here in America-save freight to the colony. I’m waiting for a response form Dometic as well just looking for your input. Thanks

 

Still adding to mine. Fabricated a small platform for my circuit breaker and relays now

 

Simple, but clean.

 

Let the games begin......

But not today. I'm hoping I can get to it tomorrow. I will post up the results.