Wiring Fuse Block for 12V Accessories

R

Road Journey

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Want to place 12 volt battery in trunk, place fuse block below under the dash & wire couple 12 volt accessories to fuse block. Where would positive & negative leads from the trunk battery normally be connected to this type fuse block. The two tall posts? The accessories to the fused screws on left?

This fuse block is Sierra FS 40540-1 at https://www.westmarine.com/buy/sierra--fuse-blocks--P010499432. Am open to suggestions on more suitable fuse block.
 

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the large post on the left just acts as a common feed. the large post on the right hand side would be the earth. the screws on the back of the fuses go to the accessory.
 
I use a fuse block like this. Boat supply places normally carry this type of electrical hardware.
 

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Is your vehicle still 6 v positive ground? Are you going to ground the 12v in the trunk to pos? I know little about electricity, but doesn't the ground (frame) carry the load as well? I used to tow a tandem axle trailer behind my stock 6 v pos 38 truck. The trailer brakes were wired to a tongue mounted 12 v battery and neg ground. Years later I wondered what happened to those electrons meeting each other at the trailer ball. Could this be a problem for your modification?
 
Be careful when using generic marine fuse panels. I have one on my test stand, and the metal "thingies" that hold the fuse itself aren't very "springy". Every time I change a fuse, I have to squeeze them together with a pliers to make sure I get good contact. Check it out before you plunk your good money down.
 
Do a Google search for " adding auto accessory fuse block ". With the battery in the trunk and the fuse block under the dash it would be prudent to have a fuse near the battery to protect the feed going to the dash. I would also recommend a fuse block that used standard automotive fuses like ATC or ATO types.
 
Road Journey: I don't know what you're working on or how original you want to keep your car but I'm with BillM above .... because of natural long-term corrosion of metals due to moisture in the air, I believe "blade" type ATC and ATO fuses provide a longer lasting and more positive connection than glass tube fuses (i.e. contact area). I also think its a little easier to see a burned element in them. i.e. witness how long car manufacturer's have been using them.

Regardless, I recommend reading up on the internet about wiring systems, connectors, fuses, etc. before you go very far. I upgraded (made safer) my '47 system and read what http://www.madelectrical.com/ had to say. The author's been around for a while and is/was an insurance inspector regarding vehicle fires. He has some sound ideas about how electrical systems can be made safer. I didn't adhere to all of them but used many such as reducing electrical resistance in the system, selecting wire, making wire connection, using relays, etc. He may be in the business a bit but good to read his ideas. And to be sure, there are others on the internet that offer good advice.
 
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tubman said:
Be careful when using generic marine fuse panels. I have one on my test stand, and the metal "thingies" that hold the fuse itself aren't very "springy". Every time I change a fuse, I have to squeeze them together with a pliers to make sure I get good contact. Check it out before you plunk your good money down.
Click to expand...

Believe the're brass construction, I don't change fuses every week!!! LOL :)
 
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