Installing an accessory fuse box

This is currently not visible to the general public, so make as many notations as you'd like (Ryan will have to copy and PM). My comments or questions are in bold italics (you're welcome :) ).

We need sourcing ideas for the Bussman.

Why? My bike already has a fuse box

Yes, it does, but it's not really set up for the use of accessories, or farkles, as they're often called. A new fuse box will allow you to connect other electronic bits such as GPS, radio, or heated gear and have each unit fused individually.

Defining terms

You will see auxiliary power supply boxes labeled 'distribution blocks', 'auxiliary fuse boxes', and most likely several other things. The important thing is you want a box that will allow you to have a separate fuse for each accessory. That way, if one gets overloaded and the fuse blows, you won't lose everything else.

What kinds of boxes are there?

There are a few different types of fuse/distribution blocks. Some distribution blocks treat each attachment point as a separate entity, requiring that power be sent directly from the battery to each connection point on the block (individual circuits). The Centech AP1 is like this. In this case you can daisy chain (make very short connections) the power wires from one connection to the next, instead of running a wire from the battery for each. This article does not cover this type, as it's more difficult to do.

The Eastern Beaver FB-4 also works this way, but it comes in a kit with everything wired for you. This is the easiest reasonably-priced box to use if you haven't done this sort of thing before.

Other fuse blocks have only one connection to power; this connection powers all terminals after the main connection receives power (aka common bus). This is what is used in the photos for this article, the Bussman 15600 Series ATC Fuse Panel. This is still relatively easy to wire up, looks 'cleaner', and is cheaper. Having someone who knows something about electronics to hold your hand is a good idea if you do this, though.

There are some advanced boxes that let you wire some things hot all the time and have others that only get powered when the key is on. The Centech AP2 is one of these.

Finally, if you're scared about hooking everything up (you don't really need to be) the Fuzeblocks FZ-1 comes with an internal relay, constant or switched power choices, and only needs a few connections.

Things to buy

• A fuse box, naturally. See above.

• A 30 amp, four-pin relay. Numbers on the relay pins should be 30, 85, 86, and 87. Pay no attention to the #87a pin on the relay in the pictures. Bosch, Omron, and Hella are all good quality. See NAPA, Radio Shack, or a local electronics shop.

• An inline fuse holder and 10 amp fuse.Take the fuse out of the holder and don't connect anything to the battery until everything is in place.

• Several feet of flexible stranded copper wire. 14 gauge is generally recommended. Positive/hot/+ is usually red. Use a different color for ground (negative). Always use stranded wire in auto/moto applications. Pictures show stranded (left) and solid (right) wire.

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• Crimp connectors

• Heat shrink tubing (optional, but a good idea for covering splices)

Or the kind of connectors that already have heat shrink on them.

• Dielectric grease - again optional, but a very good idea.

Hooking it up

For the purposes of this article, we will be following the installation of the Bussman 15600. If you are using one of the Eastern Beaver units, hook the relay up the same, then follow their directions. Mounting will be virtually the same as with the Bussman.

Once you get all the wires in place, it's simply a matter of finding a place for the box & its relay and mounting them. As always, try to test everything before mounting, in the interest of saving time if something gets hooked up wrong.

This diagram needs a few more details; Ryan says "It could use the pins that you need to attach to and where the wires are going".

First, wire up the relay. Do this before you install it, so you don't have to take stuff apart if it doesn't work.

Why a relay? With a relay, you use the OEM wiring to power the relay, and then put in new wiring for the fuse box. The relay uses a small amount of power (the horn circuit) to turn on and off a bigger amount of power (the new heavier wire) to the new box. This is true for bigger headlights or any other higher-current-draw accessories you want to add to your motorcycle.

Relay terminals

• 30 positive from battery
• 87 new positive to fuse block
• 85 positive from horn circuit
• 86 ground But where? Is it safe to say: Run it back to the battery negative?

Details

• The main power comes from the battery, through the new in-line fuse holder, to the #30 pin on the relay. The fuse holder wire might not be long enough to reach the relay. If so, crimp in a longer wire. Always keep the unfused portion of a wire as short as possible, so try to hook the fuse holder directly to the battery, then run the longer wire to the relay (after the fuse).

• Terminals 85 and 86 are the 'trigger' circuit. This is what makes the relay fire. When a circuit is made through this pair, by turning the key on, a switch on the pair 30-87 is toggled from open to closed. When this switch is closed, 30-87 are connected; this connects the battery to the new fusebox and powers your accessories. For this install the positive side (85) was taken from the horn circuit at the stock fuse box. The ground (86) goes to ______________

• Terminal 87 gets hooked to the main positive connector on the Bussman box.

Installation of the Bussman box

We'll finish with the wiring instructions first, but in order to know how long to make the wires you really have to figure out where to mount everything, so read the whole article first, OK?

The Buss doesn't provide a 'ground' terminal on their unit. So, you can add a ground post (lower right corner) to compliment the power lead. Do this by blah, blah, blah....

>>rats4ever: *Edit* Did you run a wire from the ground post to the negative post on the battery or the frame anywhere?

>>Michael: Yes, a bolt & washers; it runs back to the battery ground.

Here's one problem I had from the beginning. It looked to me like the ground bolt was just sitting in a piece of plastic. I realize now that the Bussman must be metal there. It could use a few more directions. So, I assume you have to drill a hole through the Bussman case, run a bolt through, then use a bolt, washers, and those lock-washers-that-aren't-really-lock-washers to mount the ground post.

Connect the positive lead from the relay (pin 87) to the positive terminal on the Bussman (red wire).

You can mount the fuse box anywhere you want. Our man determined that the best place for him was on the left side, in between the coolant reservoir and the CDI.

How were these holes drilled, and what in? It looks to me like something plastic, and about 8" deep. Or were they already there? (I think that's an original question from before Michael deleted all his PMs and I gave up on this article.)

The Buss provides four mounting holes. Only two were used, and the box was mounted diagonally.

Sealing the heat shrink connectors with a small torch, instead of the usual butane lighter.

Find a convenient point and mount the relay

Any suggestions as to where?

Next comes the fun part: cutting into the wiring harness at the OEM fuse block. Consult the schematic to determine which connection to tap into. Don't use the unused 'accessories' fuse because those two connections are always hot. This also goes for the OEM accessory wires. The horn was the circuit tapped into, since it has minimal draw when not in use. The schematic showed the wire needed to tap was the lower harness brown/white wire. Double-check this by testing voltage outside the sheath, then pulling the fuse.

define sheath; yeah, I know what you mean, but I can't explain it.

We still need to discuss where to run the grounds for individual accessories.

The final product. Two accessories are already hooked up, with the 5 and 10 amp fuses. Two more are pre-wired for future farkles.

Make sure all the connections are connected, mounting points tightened, and you're done. Our home mechanic says, "My Bussman setup cost me about $15, including the relay, wiring and end connections. I've been very happy with it. I've had no averse weather issues with its 'open' design. The two factors that have helped make that occur are its location and the use of dielectric grease."