[Espeefan]

A couple more things I wanted to point out - Your negitive wires become your 'common'. What I mean when I say that is this. All the negitive wires are of the same polarity, potential, and tied together. If you like, you can tap any negitive wire, from any circuit, into another, and your circuit will be complete. Multiple, seperate circuits can share the negitive wires without a problem. As long as one negitive wire makes a connection back to the battery pack or terminal block, you can solder any other negitive wire to it. The wires share the common link to the negitive terminal. One thing to consider if you decide to tie multiple negitive wires to just one negitive wire, is to be keep in mind the size of the wire. Don't tie all negitive wires from multiple circuits to one common wire alone. You could be asking to much of the single wire, to handle all the current flow of the other circuits. Best to use a heavier wire for the one common, or to simply tie the negitives together where it is convenient, for the sake of simplicity or neatness of the wiring, but for other circuits, run the negitive back to the main terminal.

Also, your switching control should be done with the 'hot' wires. The positive wires. This way the power is off, when the switch is off. If you control the switching with the negitive wires, the circuit works the same way, however the potential voltage is there and waiting in the circuit, where your loads are. In industery or residential wiring this is a bad thing. A circuit has the potential to be 'live', even if the switch is off. The voltages are not going to hurt you here, but it's good habbit to let your switch kill the power to anything down stream of it.

The last thing I would like to add is this. It's a good idea to have some short circuit or over current protection in your wiring, in the form of a fuse, or re-settable circuit breaker. Should anything short out, your wiring will be safe and nothing will melt. Size your fuses just slightly over the max current draw of your circuit. To do that you will need to calculate the max current draw. It is not absolutely necessary to have some circuit protection, but it is something to consider.

I hope this information will be helpful to those of you who are trying to figure things out. I may draw up some other circuits a bit later, but the principals of these applies to any you may design on your own.