If you are using a power cord, the wires should be colored white, black, green. The blackwire is the hot or positive wire. White is neutral, and green is common. Before wireing in your fan, is it a 110Volt fan? if not, do not hook any of these wires to your fan or you will fry it on the spot as soon as power is turned on. Most pc fans are 12volts DC. If that is what you have, you will need a 12V power supply to run your fan. A computer power supply or a 12v wallwart will work.
The thermostat and lightbulb are easy. Hook the Blackwire to one side of the thermostat, to the other side, take a cutoff lenght of black wire and hook it to the opposite side of the thermostat and the other end to the light socket. On the opposite side of the light socket, hook a white wire between the socket and the white wire on the power cord. This will complete your circuit. Whenever the temperature drops below the thermostat setting, the light should come on. If you look closely at your thermostat, it may or maynot have a third screw for attaching wires. This screw is normally greenish in color. If your thermostat has the green color screw, this is where you hookup the green colored wire from your power cord. Also, your porcelin light socket may or maynot have this same green colored screw. If so, hook a green wire from the green screw on the thermostat to the green screw on the light socket. If your thermosat or light donot have the green colored screw, you can leave the green wire disconnected, BUT, the green wire is for a common ground and is a safety feature you need to use if you can.
Now for the computer fan. If you have determined it is indeed a 12v fan, you will need a 12v power supply. The power supply should have a black and white wire going to the supply and two other wires, can be different colors, but most likely one black and one black with white stripe, that go to the 12V device. You can hook these wires up to your fan in either direction, if the fan runs backwards, just reverse the wires. The black, white, and green wires will hook directly to your black, white, and green wires on your power cord. If the power supply doesnot have a green wire, dont worry about it, just hook black to black and white to white on the power cord.
If the fan is a 110V fan, it should have a black and white wire, could be red and white. In either case, the white is always neutral and the colored wire is hot. It could also have a green wire, which is again a common ground. In this case, the black wire from your power cord would hook to the black or red wire on the fan, the white wire to the white wire and green wire to green wire.
These wireing instructions do not take into account for any on/off switches in your circuit. If you intend to use switches, you will need two toggel switches to operate each circuit. To install these switches, you will hook the black wire from the powercoard to each toggle switch. From one switch, you will use a black wire to run to your thermostat, instead of the blackwire directly from the power cord, and on the other switch, you would run another black wire to the fan power supply, instead of a blackwire directly from the power cord. This will enable you to turn on and off each circuit without effecting the other circuit. This will keep you from having to unplug your incubator everytime you want to turn it off and on.
If you are still unsure as how to wire this up, dont tryit without asking more questions or getting someone to help that does know. 110v electricity may or may not kill you the first time you get shocked, but it will darn sure hurt.
I have a water heater lower thermostat(90*F-150*F), a porcelain light bulb socket, a large PC fan (NOTE: This is NOT a normal PC fan!!!!!!!! Scroll down a few posts for pictures!!!), two homemade egg turners, digital temperature meter with probe and water wiggler, my 100q Igloo ice chest, and non-digital humidity gauge.
