Power Distribution Box
by Mark Coker - KC7JOG

One of the oft overlooked items when setting up a remote station in the field, is where to get power and how to distribute it. This project is a suggestion and is how I did it. While the metal box used looks nice, working it was quite a chore. Other materials can be use, including wood.

A brief description of this unit will tell you that it is designed to clip onto the battery terminals of a near-by vehicle. A heavy battery cable with a length of 35 feet (suggested) feeds into the box. The box contains various fused output connections to connect your equipment to, and it also contains optional meters so that you can monitor the battery voltage (a good idea if you want the vehicle to start later), and an Amp meter to allow you to monitor power draw.

There is no wiring diagram mainly because this is nothing more than a simple DC extension cord that allows numerous parallel taps off the primary feed cable. Wiring should not be a problem.

The question was asked; "why build this box? Why not just use a "RigRunner" power strip and be done with it. The answer is you can build this box for under $50 and the RigRunner strips and Power Pole connectors are quite expensive in comparison. (click here to see what I mean.)

Left meter is 0-50 amps.
Right meter is 0-15 volts.
Green light on when power is present to box.
The lower left switch powers the 30 amp bananna recepticle on rear.
Orange light above it, lites when its in the on position.
I intend this outlet for a 120 volt ac, 200 watt power inverter.
The front switch is rated at 45 amps

Parts requirement for this configuration:

Heavy Battery Cable about 35 feet in length.
(3) cigarette lighter recepticles, all fused at 5 amps
(2) bannana pin recepticles, 1 fused at 12 amps and unswitched.
the second recepticle is fused at 30 amps, and is switched via front panel.
1/4" bolt terminal assembly fused at 30 amps.

You will also need fuse holders to hold your fuses, and it is not a bad idea to include a few spare clips with spare fuses.

The first step is to buy the heavy wire for the battery cable. If you are able to get stranded wire the cable will be flexible. You might even just purchase a set of battery jumper cables (if you can find a pair long enough) and use them. You do need heavy wire, at least 6 or 7 gauge.

One good idea for the heavy cable, get easy to find 10 gauge wire and use two red wires and 2 black wires in parallel(red and black pairs are separate of course) and you can run them through a garden hose, which will hold the four #10 wires. This makes a very nice, flexible and easy to store cable. Two parallel #10 wires are equal to one #7 wire according to the book.

Inside the box

As stated earlier this project is presented as an idea and how I did it. You would be encouraged to take the ideas and come up with a power distribution box that best suits your needs. Trust me when I tell you that when you need to set your station up in the field, and all you have is vehicle battery power, a box similar to this one is a must.