Auxiliary Fuse Block Wiring

[caseycamby]

I have my eyes on this bad boy (CLICK ME) and have a few questions that I haven't found definitive answers on yet.


1) What gauge wire should I run to the battery from the fuse block? Is that dependent on what I'm going to add or is there a general go to size. If I read it correctly, the max the block can handle is 100 amps. Should I account for that and use whatever size the chart says for the length of wire I need?

2) On the same wire from the fuse block to the battery, should I have an in-line fuse or circuit breaker? What are the pros and cons, if any? Should the size of the fuse/circuit breaker be dependent on what's currently hooked up to the fuse block or just 100 amps?


Also, if anybody wants to add any insight or advice on what I should or shouldn't do, it will be appreciated!

 

[Prime]

I ran 8GA to mine and have a 100A inline fuse right off the battery. That feeds all of my auxiliary lighting and my stereo amplifier.

In more direct response to your questions, fuses are never really a bad thing unless they're too small. Always place large fuses as close to the battery as possible (and reasonable). Like under the hood...not wherever you mount the fuse panel.

Technically, the size should be a sliding scale, but in all reality, 100A is going to cover you really for just about everything.

 

[caseycamby]

Right on. My plans are to mount this under the hood so that shouldn't be a problem there.

Do you think I'm good getting the one with out the negative terminals or am I missing out by not getting it?

 

[Prime]

Personal preference really. The entire truck is a ground. So you can drop those on any bolt you can find rather than running them all the way back to the box. IMO, it makes it easier that way than running a ground all the way back to the box.

 

[caseycamby]

Personal preference really. The entire truck is a ground. So you can drop those on any bolt you can find rather than running them all the way back to the box. IMO, it makes it easier that way than running a ground all the way back to the box.

My exact thoughts. Thanks!

 

[mudchet]

I am doing the same thing Casey. 8 gauge should be fine. The fuse block is rated to 100 amps max, so having a fuse for 100 amps makes sense. If you put a 200 amp fuse in there the fuse block will melt before the fuse blows. I use a breaker instead of a fuse. I really like the convenience of being able to shut off all my auxilliary stuff when i need to but they cost more than a fuse. I also use the fuse block with the negative terminals. For lights and stuff tou can go wither way. Winches, inverters and high amperage devices should have a cable going to the negative terminal of the battery vs using the truck as a ground.

 

[Prime]

That's a good point. There are some things that are better to run directly to the battery for ground.

 

[caseycamby]

Yeah, that is true. I guess in those special instances I can run it directly to the battery. I already have my winch that way now.

 

[thecoalition]

Jay - what did we run to mine? I feel like we used 6awg or maybe 4awg? And yes Casey we also dropped an inline fuse on it.

 

[Prime]

We ran 8ga

 

[caseycamby]

Just another quick question pertaining to this..

On the 86 post of the relay, you have to have power to go through the switch to trigger the relay, right? Where do you guys get the power from? You only need just a little of power, correct?

 

[Prime]

Yes. The power comes from the output of the switch. And a 5A circuit is enough to run all of your switches to the relays.

 

[caseycamby]

Okay so you're saying on one of my terminals from the blue sea, I need to run power to the cab to give power to the switches?

Is that where the distribution block comes into play?

I'm sorry.. I'm wiring dumb but I'm learning haha

 

[thecoalition]

Ok Jay and I looked at mine today - we ran 4awg from the batter to the blue sea.

Casey - you should have it wired like this Switch > Blue Sea >Battery - the blue sea is distributing power to everything hooked into it. Now I believe that you will need to tap another wire for lights on the switches if you have the independant/dependant type.

 

[Prime]

Okay so you're saying on one of my terminals from the blue sea, I need to run power to the cab to give power to the switches?

Is that where the distribution block comes into play?

I'm sorry.. I'm wiring dumb but I'm learning haha

Yes. One circuit on the blue sea with a 5A fuse will power all of your switches. You'll need to tap splice the pink wire in the day to run dash illumination if your switches support it.

It's complimicated.

 

[caseycamby]

Yes. One circuit on the blue sea with a 5A fuse will power all of your switches. You'll need to tap splice the pink wire in the day to run dash illumination if your switches support it.

It's complimicated.

Was that a yes to the distribution block as well? Is that the best way to splice the wire out?

 

[Prime]

12v from the blue sea on a 5A fuse. Loops through on all of your switches that go to relays.

Those switches send that 12v to the relay and trigger the heavier load.

 

[01XterraPhilly]

i have a question about these...do they have relays or just the small fuses?

 

[Prime]

The panel Casey linked to is simply fuses. They do make some that have relays as well.

 

[01XterraPhilly]

so this would be something that you need to wire a relay to the fuses?

 

[Prime]

This merely serves as a convenient place to pull power from for your accessories. If you need relays they would be separate from this particular panel.

 

[01XterraPhilly]

oh ok...never really understood how they worked. im currently in the process of rewing a fuse block from a cherokee. its nice bc it has fuses hooked up to relays in one box. plus it was $15 from a junk yard

 

[caseycamby]

Jay I totally forgot to call you today. It completely slipped my mind. Is there a good time to call you tomorrow?

 

[Prime]

No worries. Any time after 5 tomorrow

 

[caseycamby]

I'll try to remember this time! Sorry haha

 

[Txterror]

if you are wanting a one shot solution of sorts, there is the S-Pod that has built in power management and relay system into one unit. Just hook-up your switches or spend the insane amount for the touch screen. It is very user friendly, but extremely expensive.

 

[caseycamby]

So I think I get it now.. My only question to figure it all out.. How can I regulate the amps coming out of the blue sea to give power to the switches? Probably about 5 amps or so. How can I make sure it's not gonna throw 100 amps to the switches haha

 

[Muadeeb]

Current (amps) does not really work that way. The amount of current drawn is based on the load (resistance) of the circuit. The switches do not add any (meaningful) load unless they're bad.

So if you have a switch on a relay, then you only have a few milliamps running through that circuit. On the load side of the relay, you may have 30 or more amps being controlled. The relay is how you isolate the high current loads from the switch.

 

[caseycamby]

Right. That makes sense so it's only gonna draw as many amps as it needs.

 

[mudchet]

V= I x R

V = volts, so 12 for most automotive situations.
I = current, measured in Amps
R = resistance, measured in Ohms.

So I = V / R.

 

[Prime]

Right. That makes sense so it's only gonna draw as many amps as it needs.

Right. Another way to think of it...

Amperage is demand based. A device will draw what it needs.

Voltage is supply based. It'll give you what it can.

 

[caseycamby]

I totally got it. Pictures of new things shortly!

 

[caseycamby]

Wahoo!

 

[thecoalition]

Make sure you buy fuses to put into it.

 

[caseycamby]

Make sure you buy fuses to put into it.

Couldn't do it without you bud

 

[thecoalition]

Hey man - just gotta keep you in check

 

[caseycamby]

That you do.... that you do.

 

[caseycamby]

More goodies! BWD 100A circuit breaker. And with that.. A couple more questions.

What's your thoughts/opinions on running the ground wire off of the relay to a switch inside the cab and use the switch as an interrupter of the ground. And of course, wiring the relay accordingly.

Also, your thoughts/opinions on using dielectric grease on all the connections.

 

[mudchet]

Grease : I haven't found a need for it. I have wheeled my rig in mud and dust and not had issues that grease would have fixed.

Regarding your wiring design I would need to see a diagram in order to give you good feedback.

 

[Muadeeb]

The only time I used dielectric great I melted a socket and shorted out my interior lights