Adding a “Switched on” auxiliary fuse box?

[silvermachine]

Hey all, trying to wire up an auxiliary fuse box for some low power accessories. Fans, radio, USB ports, etc.. Currently, I have the aux fuse box wired directly to the battery. Everything is on unless the battery cables aren’t hooked up.

Obviously, that’s no good and will drain my starter batteries quickly, so I want to wire this fuse box to the ignition to be switched on only when the key is turned.

Seemingly an easy job, but there’s honestly just so much information out there and I’m looking to simplify and make it work for me.

The auxiliary fuse box is 12 circuit and 100A, so I know I need an inline fuse between the battery and the relay. Just not quite sure how to hook it to the ignition.

I’ve attached a diagram which I believe is correct for my purposes.

Terminal 86 on the fuse relay would go to the ACC circuit slot on the car fuse box with an add-a-circuit fuse tap?

Alternatively, terminal 86 could just be its own switch OR one of the “switched on” ignition wires right?

Diagrams or links to products are always appreciated! Thanks for helping out.

[CHEESE_WAGON]

Here is a more detailed and specific schematic that I created for this type of relay... Not all of these will have an 87a terminal, as they are not required on all applications. The schematic you posted isn't loading completely for me (sides are cut off), so if you weren't already planning on it, I would say you want to connect 30 to the battery, and 86 to the ACC circuit, if there is one. If not, you can put it on a switch. 87 will be your output for your accessories.

[BlackJohn]

You have a 100 amp panel and are happy feeding it with 30amps?



This doesn't seem kosher.



How many amps is the ACC fused at now?


How many amps with 12 circuits will you be expecting to use?


You won't need any of those circuits while vehicle is running?


John

[JackE]

Your diagram is correct. The problem I see is your supply needs to be a larger gauge wire and run through a much larger relay. I would get a 100 amp continuous duty relay for that purpose. That way you will never overload the fuse panel. You could probably even cut it down to a 50 amp and be fine. Your relay trigger wire could easily come off any 'hot in run' circuit.