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Ag Power Web Enhanced Course Materials

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A conductor is a material (usually a metal such as copper) that allows electrical current to pass easily through. The current is made up of electrons. This is opposed to an insulator which prevents the flow of electricity through it.

Wire Anatomy

Anatomy of a Wire

The diameter of the wire is usually an indication of the amount of current it carries. The larger the wire, the more current it can carry. As an example of this, look at most of the wires, they are relatively small. Now look at the main wires coming from the battery. These wires are quite large as they must supply a lot of current when trying to start the engine.

The thickness of the insulation is an indication of the voltage in the wire. Again, most of the wires in a tractor, have very thin rubber insulation on them. However, if you look at a spark plug wire, you will see that the insulation is thick when compared to the size of the wire.

Also notice that most of the wire in a tractor is stranded. This means that a wire is composed of many smaller wires. Tractors and other Ag equipment use stranded wire because stranded wire bends and withstands flexing much better than the solid wire.