Add-a-Fuse Setup for Multiple Signal Wires

Hey everyone,

I'm looking to add more to my add-a-fuse setup, specifically everything I want to turn on once my key is turned. My question is: can I add multiple devices to a single add-a-fuse, or will that be too much for one circuit?



The add-a-fuse won’t be directly powering most of these devices. For example, it will only power the Raptor lights. The other devices, like my switch panel and headlights, are using the add-a-fuse as a signal wire — basically letting them know to power up when the key is on.


I have two scenarios in mind if this might be too much for one add-a-fuse:

1. Using a Relay: Could I add a relay with a fuse, using power directly from the battery? The add-a-fuse would just trip the relay and send power to the devices. My concern is if that would send too much power to the signal wires. Is this setup the same as wiring the relay trigger directly to the battery? (
   $12 Gebildet 12V Fuse Relay Switch Harness Set - 30A ATO/ATC Blade Fuse, 4-Pin SPST Automotive Electrical Relays with Heavy Duty 12 AWG Wires (Pack of 3)
   Amazon.com: Gebildet 12V Fuse Relay Switch Harness Set - 30A ATO/ATC Blade Fuse, 4-Pin SPST Automotive Electrical Relays with Heavy Duty 12 AWG Wires (Pack of 3) : Automotive)
   
   
   
   
   
   
2. Splitting the Load: Finding other fuses that are also ignition-switched and using them to distribute the load. I want to avoid this, though, to minimize the number of wires going through the firewall.

Would appreciate any advice or recommendations on whether the add-a-fuse alone is sufficient or if a relay setup is necessary here. Thanks!

 

I’ve put multiple outputs from one add-a-fuse for signal/turn on wires and just fuse it pretty low at like 1-2 amps. Not really an issue.

But I’d keep the raptor lights on a separate add-a-fuse circuit.

And if you start wanting to add additional items with power on with ignition only, then you can have a relay setup to an auxiliary fuse panel and have a trigger trip the relay for your panel when key is in the ignition. Keeps things cleaner and overall safer than like 3-4 added fuse circuits coming off the interior fuse panel.

 

I thought about doing this as well, but it contradicts my recent switch panel install to clean up under the hood lol. So this would look something like this?



Using these:

$14 True Mods 6 Way Blade Fuse Box with Ground Negative Bus bar for Automotive [ATC/ATO Blade Fuses] [100 Amp] [LED] [Protection Cover] [12V - 30V DC] Auto Marine Ground Fuse Block

Amazon.com: True Mods 6 Way Blade Fuse Box for Automotive [ATC/ATO Blade Fuses] [100 Amp][LED Indicator] [Protection Cover] [10-30V DC; 12V] Auto Marine Fuse Block : Automotive

$12 Gebildet 12V Fuse Relay Switch Harness Set - 30A ATO/ATC Blade Fuse, 4-Pin SPST Automotive Electrical Relays with Heavy Duty 12 AWG Wires (Pack of 3)

Amazon.com: Gebildet 12V Fuse Relay Switch Harness Set - 30A ATO/ATC Blade Fuse, 4-Pin SPST Automotive Electrical Relays with Heavy Duty 12 AWG Wires (Pack of 3) : Automotive

 

Yes your diagram is correct. I just meant more along the lines of if you find yourself utilizing a lot of in-cab add a circuits for items you don’t need a switch for but want to turn on when the truck is on, it’s nice to have a small auxiliary interior fuse panel for these low amperage items.

For a couple items to the OEM interior fuse panel it’s not a big deal.