Question Regarding Accessory Fuse Block (1 Viewer)

[SammyB]

I'm really sorry to have to ask this basic question, but I'm not well taught in the electric field. I searched this forum and online and still can't find my answer. It's probably right in front of my face but I'm still confused. Criticism to my stupidity- Allowed.

I bought a Blue Seas fuse block (with bus bar) and a Bussman 100amp circuit breaker. I want this fuse block to be hot only when the ignition is on. I understand you get power from the battery and then tap into the ignition wire itself normally to attain this. Where I'm confused is this: If I'm tapping into the ignition wire by the steering, isn't that only a 14 gauge wire? How is that going to withstand all the accessories this fuse block is going to power?

My next question is do I run my 10 gauge wire from the + side of the battery, to my circuit breaker, to my fuse? Or is the ignition wire the positive, and I would run my 10 gauge from the - side of the battery to the circuit breaker to the fuse block.

I'm embarrassed to have to ask this.

 

[ChaseTruck]

Use that little 14 ga wire to trigger a relay/solenoid/contactor that'll provide the actual power to the fuse block.

 

[sunrk]

You can't run circuits with up to 100 amp load *directly* from any circuit that is being switched through the ignition switch assembly. I'd hazard a guess that the ignition switch wiring wouldn't be good for anything more than 10 to 15 amps.

I don't recall whether the factory DC distribution block (in my 80 it's behind the right side battery tray bolted to the inside of the inner RHS fender panel) has a supply of 'on with ignition' power or not, but if it does you can get a low-current 'signal' to use for switching a high-current relay from there.

Maybe a cheap dual-battery solenoid could be used to switch a high-current (and fused - don't forget that) feed direct from battery positive to the Blue Sea fuse block. Be sure to not exceed the load capacity of the fuse block itself.

I have a blue-sea fuse block btw in my 80's dash but I don't use it for high current stuff. It connects to the auxilliary battery and I have it 'always on' but every circuit it feeds is seperately fused.

 

[REKCUT]

Why even power it that way. Run the system on its own with a power switch so yo can chose to have it on or not. Lighted switch in full view to remind you to shut it off if your worried.

 

[bigredmachine]

you could just add a battery switch for the accessory block

e-Series On-Off Battery Switch - Blue Sea Systems

350 Amps continuous rating for inboard gasoline or diesel engines.

www.bluesea.com

what are you running the accessory block for, are they things that will be used occasionally or was it added to make install easier? if its for tiems that will be rarely used such as camping gear then maybe the swith would be the way to go, turn it on when you need it turn it off when you don't. if its for items that you plan on using regularly then you would want to run power through a relay with a signal from something that would be hot key on

 

[chap79]

I’m running the blue sea split bus fuse block. I have 4awg wire going from the battery to a 100amp breaker then on to the A+ of the fuse block. This side of the block is always hot. I then have a 40amp relay that gets its + from A+ and supplies the power to the B+ side of the fuse block via 10awg. The relay is triggered by accessory power. I only have led lights, dash cam, gps, USB port, and switched dash lights power being run off the switches side. Fuse block grounds back to the battery

 

[george_tlc]

You can't run circuits with up to 100 amp load *directly* from any circuit that is being switched through the ignition switch assembly. I'd hazard a guess that the ignition switch wiring wouldn't be good for anything more than 10 to 15 amps.

I don't recall whether the factory DC distribution block (in my 80 it's behind the right side battery tray bolted to the inside of the inner RHS fender panel) has a supply of 'on with ignition' power or not, but if it does you can get a low-current 'signal' to use for switching a high-current relay from there.

Maybe a cheap dual-battery solenoid could be used to switch a high-current (and fused - don't forget that) feed direct from battery positive to the Blue Sea fuse block. Be sure to not exceed the load capacity of the fuse block itself.

I have a blue-sea fuse block btw in my 80's dash but I don't use it for high current stuff. It connects to the auxilliary battery and I have it 'always on' but every circuit it feeds is seperately fused.

The 'factory DC distribution block' does NOT exist on USA 80's - not needed for soccer mum duty...

cheers,
george.