External fuse block

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FullyLitLED

FullyLitLED

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Hey guys, as I plan out my upgrades for my 100 series, I came across several rigs with external fuse blocks. I am pretty sure that I can add my external fuse block with some help, do you guys have writeups on adding external fuse blocks? Or maybe a link to a VERY detailed writeup, since this is the first wiring job I will do on my 100 series landcruiser. I have seen several systems with a circuit breaker located in the hood but I want to know if it is possible to put the circuit breaker in the actual truck near my oem switches so it can be shut off without having to open the hood. Im hoping my setup will allow for all the added accessories that are connected to the external fuse block will shut off when the vehicle is turned off. Thanks in advance guys!
 
Here is a small one with the relay built in, that I used in my 40. It's made for motorcycles but works well in Cruisers too. The limiting factor is that there is only room for six connections. If you're going to run more than six accessories off of it, then you'll need to use a Blue Sea or similar larger fuse block. The cool thing about the Farkleshop fuse block (besides the built-in relay) is that you can choose on each and every connection whether you want it on with ignition only or always on, and you can change back and forth instantly just by moving the fuse.

Farkleshop aux. fuse block

Installed in the Con-Ferr box behind my front seats:

fuseblock001.jpg
 
That is awesome! Did you hook that up to your original fuse box or is it completely separate?
 
More questions:

1. I know there are only 6 spots on the fuse block in the link provided, if I run out of spots on the first fuse block, can I add another fuse block or is a vehicle strictly limited to one?

2. (it says each circuit is capable of 30amps each so a total of 180amps for the entire fuse block, right?) Is the individual 30amp rating good enough for a winch, fog lamps, cb radio, fridge/compressor?
 
Check Blue Sea for a variety of different fuse blocks in many different configurations. I would add a thermal breaker in series as close to the battery as is practical.

You can run as many sub-fuse blocks as you have the power to support.

Fuse blocks will have a total amperage rating and a max rating for each circuit, the combined current (amps) for all circuits should not exceed the max rating for the block. You will want to size the fuse on each circuit according to the load EX you wouldn't use a 30A fuse on a device that typically draws 5A. The idea of a fuse is to protect the wiring and devices on the circuit for bursting into flames. You will also need to size the wire used in each circuit for the amount of current needed.

High current loads, fog lights compressors etc., are usually controlled with a relay. (BTW you would never run a winch through a fuse block, they use a LOT of current and are usually wired directly to the battery.)

A couple of questions;
Do you want the fuse block hot at all times? Or only hot when the ignition is on?
If you want it ignition hot only you will need a relay.​

Do you plan to run a second battery to power accessories?
A second battery is common when you have something like a fridge that will run 24/7, it gives you a way to power accessories at all times with out compromising your main (starting) battery.​

Hope this helps more than it confuses you.
 
LJ_24 said:
That is awesome! Did you hook that up to your original fuse box or is it completely separate?
Click to expand...

No, it goes straight to the battery so it is completely separate.


LJ_24 said:
More questions:

1. I know there are only 6 spots on the fuse block in the link provided, if I run out of spots on the first fuse block, can I add another fuse block or is a vehicle strictly limited to one?
Click to expand...

You can add as many as you want, but it would be much more practical to determine ahead of time how many accessories you're likely to add and just do one auxiliary fuse block with sufficient connections.


LJ_24 said:
2. (it says each circuit is capable of 30amps each so a total of 180amps for the entire fuse block, right?) Is the individual 30amp rating good enough for a winch, fog lamps, cb radio, fridge/compressor?
Click to expand...

No, that one is 30 amps total for the whole fuse block. Although each circuit is good for the whole 30 amps by itself as a safety measure, all the accessories that you run at the same time should not exceed 30 amps when all added together. It's perfect for radios, gps, and could be used for a fridge but your winch and fog lamps draw too much current and need to be powered straight from the battery using a relay to switch the power on and off. Same with on-board air compressor.
 
1911 said:
....



You can add as many as you want, but it would be much more practical to determine ahead of time how many accessories you're likely to add and just do one auxiliary fuse block with sufficient connections.


...
Click to expand...

I'd add a couple of circuits more than you think you will need, it's easier than adding them later.
 
So fog lights cannot be wired to an aux fuse block?

If I get a winch, is the secondary battery ABSOLUTELY necessary? Or can a winch be run with one battery? Are winch relays sold or made to specs? Sorry for being nit picky, I am new to this. If the winch and fog lamps will not work with an AUX fuse block, I might not even need 12 circuits
 
Winch is battery direct...and TOP post only for connections...do NOT run it thru a fuse block...

I run a Bluesea off my 2nd battery, use 6ga wire (I think) with a large fuse just off the battery, then the run back to the external fuse block. Mine runs all circuits as 'constant hot', wiring for a mixed 'switched and constant' will be different.

Amazon.com: 5028 ST Blade Fuse Block w/ Cover: Sports & Outdoors@@AMEPARAM@@http://ecx.images-amazon.com/images/I/41jOEOyNczL.@@AMEPARAM@@41jOEOyNczL - 6-fuses, lots of others out there too...

I run my CB and multiple 12v cig plug connections off the block. Fridge connection, constant-hots for phone chargers, etc...and yes, you can run the lights thru there too...no reason not to...

2nd battery is NOT absolutely necessary...but is certainly piece of mind. Be REALLY sure to connect the battery off the main top posts, NOT the side posts...using good military-type top terminal connections makes this easy :)

Wrangler NW - Power Products has lots of good stuff to shop thru...and it's priced accordingly :)

good thread here too: http://www.expeditionportal.com/forum/showthread.php?t=22091
 
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woody said:
I run my CB and multiple 12v cig plug connections off the block. Fridge connection, constant-hots for phone chargers, etc...and yes, you can run the lights thru there too...no reason not to...
Click to expand...

so I can wire IPF fog lights(KC's/procomps/other fog lamps) through the fuse block?

How do you wire the block so that it only comes on when the ignition is turned on?
 
LJ_24 said:
so I can wire IPF fog lights(KC's/procomps/other fog lamps) through the fuse block?

How do you wire the block so that it only comes on when the ignition is turned on?
Click to expand...
The advantage of using a relay for the lights is you don't need to run heavy gauge wire to the switch. You can also use a low current switch to turn them on and off.


The winch relays will come with the winch.
 
LJ_24 said:
Thanks for all the help guys. I found a store locally that sells the blue sea products. Decided to go with this:
ST Blade Fuse Block With Cover - 12 Circuit without Negative Bus - PN 5029 - Blue Sea Systems

and a 100 amp circuit breaker. I may need future help with wiring, but that will come when I am in the middle of the actual project lol What guage wire should I use?
Click to expand...

I used that exact fuse block in my FJC. If you want it to turn off with ignition, you'll have to wire in a relay.

What gauge wire you should use depends on the total amperage draw of everything powered through the fuse block that could ever run all at one time. If you're going to run your fog lights through it, you'll want some pretty heavy gauge. If I remember correctly I used 10 or 12 AWG from the battery back to mine, but I'm only running radios and a GPS off of mine. Here is a table that shows you what the maximum safe amperage is for all the gauges of AWG wire: American Wire Gauge table and AWG Electrical Current Load Limits with skin depth frequencies
 
Looks like I will be using a relay, are there any ready made relays for this project?
 
LJ_24 said:
Looks like I will be using a relay, are there any ready made relays for this project?
Click to expand...

40-amp Bosch automotive relays can be had at any auto parts place.
 
Thanks once again guys! All this stuff is being ordered and is hurting my bank account haha
 
confused and planning ahead...so I wire the relay into the fuse block so it shuts down with the truck? Is there a writeup out there on how to wire this fuse block with the relay so that it shuts off with the truck? Sorry guys, all I have done is HIDs, I dont think I have the tech know how to do anything more than that...my parts are coming monday and I really need some more help

also, when I switch the key to the "acc", will anything connected to the fuse block still be off?
 
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LJ_24 said:
confused and planning ahead...so I wire the relay into the fuse block so it shuts down with the truck? Is there a writeup out there on how to wire this fuse block with the relay so that it shuts off with the truck?
Click to expand...

Look in this FJC-specific thread on a different forum; scroll down and there is a wiring diagram that is universally-applicable. It actually shows two relays wired in because he made half of fuse block switched with ignition, and half always-on, but you only need one relay if the whole fuse block is going to be switched with ignition:

12-CIRCUIT SWITCHED FUSE BLOCK: Inst. w/ pics - Toyota FJ Cruiser Forum



LJ_24 said:
also, when I switch the key to the "acc", will anything connected to the fuse block still be off?
Click to expand...

It depends on where/what you wire the trigger for the relay to. If you want the fuse block to be on with ACC and not ignition, then you'll have to find a fuse position in the stock fuse block that is on with ACC, or tap into the stereo power wire (for example) that you know is on with ACC.
 
That is the perfect writeup! When doing the add-a-circuit, I understand that you have to find a fuse that is, in my case, on when ignition is on but off in "acc", does it matter which one? or any single fuse will work? How do I test which one I need to use?

"Once all of the under-the-hood connections have been made, you can start routing power cables from your various accessories and make the necessary connections to the fuse block. (Also, make ground connections for each individual accessory.) And, tidy everything up with cable ties as necessary."

How do you make grounds for each accesory? Is it as simple as grounding it to the fender or must they all be separate grounding points that I am unaware of?
 
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