*Portable Power Supply*
By Motorman
(11-10-02)

While a generator or other off the grid power source is ideal, it is also expensive. A portable power supply is designed to be, of coarse, portable was well as fairly inexpensive. The first thing on should note is that this is a compromise. While it is cheap and portable, the drawback is limited power. You are limited to the power in the battery, once gone you will need to recharge it. Drawbacks aside, this can be a usefull tool.
To start out with you will need a battery(group 27, deep cycle), battery case(marine), inverter, 2 electrical boxes, 2 outlets, 2 outlet covers, 1.5-2 foot electrical cord, 3 romax connectors, male electric cord end, and 10"x14" board(size depends on your inverter). Choose the two most expensive items carefully. Make sure you buy the best battery you can afford. The next item is the inverter. The plans that I had called for a 300 watt inverter. The price difference between a 300 watt and a 750 watt was only $25. I went with the 750 watt.
To start the assembly, mount the inverter on one end of the board. The ends of the inverter should be right up to the edge of the mounting board. This will allow you to connect the power cables as well as the the electrical cord. Next punch out the plugs on both ends of one box, and the plug on one end of the other box. Insert the romax(cord relief) into the 3 holes.  Mount your elect. boxes to the board. Place them on the other end of the board, allowing the the inverter plenty of space to allow for cooling. Cut your elect. cord in half. Attach your plug to one piece,strip the wire ends and put the other end in the first box.Strip both ends of the other cord, this piece of  cord will run between your two boxes. Attach your outlets to the cords, tighten your outlets into their boxes. Tighten your cord reliefs(this will take any strain off of the cord ends and outlets).  Place your covers on the outlets, and plug the cord into the inverter.


Next, place your battery into your box. Connect your power cable to the inverter and then to the battery. A word of caution, make sure that the polarity is correct. Very bad things happen when connected backwards. The power cable can be permanently attached to the battery with ring terminals. However I kept the spring clamp ends on, in the even that I needed to remove the inverter to connect to my BOV. Once the ends are connected place the box cover on and set the board on the top. The strap from my box was long enough to go around the box and the board. If your is not long enough, you may use straps or cable ties to attach it.
Now for the big test. Turn on the inverter, and plug an item in. Just make sure that the items that you plug in will not over load the system. Your item should now be working properly.

The only items that sometimes have a problem are T.V. and radios. Seems that these items do not like the power(waveform, I believe) the inverter puts out. It creates a interference noise in the item. I tried a small TV as well as a couple of different radios, and have not had a problem. Just a word of warning, in case you experience this problem. If I remember right, there is a capacitor you can put in that will solve this problem.


Hopefully, you will now have a portable power supply that when used properly can solve a great may problems.

Motorman

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