|Building the Grid (1886-1900): Exploration|
|Unplug the thick cable to the headquarters office before changing the wires.|
|Disconnect any existing power lines from your power plant.|
|Place the power plant and headquarters office at one end of your table and set the homes, shops, factory, etc. around the edges of the table.|
Each grid line should have a factory, 3 houses, and one or two other one- or three-phase customers.
|Generally, the taller the pole or the higher the wire is off the ground, the higher the voltage that the line carries. Transformers are used to change the voltage of a line. Notice that the springs on the power plant are on black transformers. They "step up" the voltage so that it can go a long distance to the customers. A substation has several transformers.|
A typical power plant produces about 20,000 VAC which is stepped up to 138,000 to 1 million volts for transmission. Power going from one substation to another is 69,000 volts. This is reduced to 7,200 volts for distribution.
|Set up several high voltage H poles in a line from the power plant to the middle of your table.|
|Measure, cut, and strip both ends of red, black, and blue wires and connect them from the springs on the power plant to the first high voltage pole.|
|Continue connecting red, black, and blue wires from one pole to the next until they connect to the factory.|
Each wire starts at a spring and ends
at the next spring. Do not use a single long wire for this step.
|Thread a white wire through the holes in the top of the H-poles to extend all the way from the factory to the power plant.|
This could be one long continuous wire.
|Cut this white wire to the right length and strip the ends. Connect them to the alligator clips on the factory and the power plant.|
Each wire starts at a spring and ends at the next spring. Do not use a single long wire for this step.
|Check your wires and turn on the power. Does the factory function?|
|Turn off the power after testing.|
|Connect red, black, and blue wires to other customers that need 3-phase electricity. Simply branch off the springs on the towers.|
|Remember that you must have a complete circuit. The electricity has to have a way to get back to the power plant. One method is to connect your white wire to an existing white wire. Cut the existing wire and strip both ends. Insert both ends and the end of your new wire into a wire nut. Twist them together with the nut.|
Connecting wires with a wire nut is a
new skill introduced here. Wire nuts
are used in nearly all electrical work. It is much more secure than simply twisting and taping wires together and much faster than soldering them.
|Check the wiring and turn on the power. Turn off the power when you are done testing.|
|Before distributing electricity to your neighborhood, the voltage has to be "stepped down." The wires you see on your street are usually about 7,200 volts. That is still very dangerous, but not nearly as dangerous as the 120,000 volts or more in transmission lines. The 7,200 volt line is stepped down again with a bucket transformer mounted on the pole just outside your house or by the transformer inside the green box in your backyard.|
|Connect a red, black, or blue wire from an H pole to one side of a transformer.|
The two terminals of the transformer are connected to each other. One wire comes into one side and that same color wire goes out the other side. NEVER attach a white "ground" wire to a transformer.
|Using that same color wire, connect from pole to pole to get to a house. The pole nearest the house should have a bucket transformer on it.|
Some of the distribution poles have bucket transformers. If you don't have a bucket transformer on your distribution pole, use another transformer to represent the green box found in many backyards.
|Hook up other wires and transformers to get power to every customer.|
|Run the white wire through the holes in the top of the poles all the way back to the power plant.|
Most power poles have a ground wire running along the top. This provides a constant "ground" as well as protection from lightening strikes.
|Connect the alligator clips of all of the houses and customers to the main white wire.|
This may require a splice be made into the white wire with a wire nut.
|When you are certain everything is hooked up correctly, turn on the power.|
|Do all customers have power? If not, what is wrong?
The usual culprit is a missing ground wire.