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purpose in hand, so the categories of insulator and conductor do have practical utility. Thermal and electrical conductivity often go together (for instance, most metals are both electrical and thermal conductors). However, some materials are practical electrical conductors without being a good thermal conductor. Conductor size In many countries, conductors are measured by their cross section in square millimeters. However, in the United States, conductors are measured by American wire gauge for smaller ones, and circular mils for larger ones.

Conductor materials Please note: Anodized Aluminum is a Non-Conductor of an electric current. Of the metals commonly used for conductors, copper has a high conductivity. Silver is more conductive, but due to cost it is not practical in most cases. However, it is used in specialized equipment, such as satellites, and as a thin plating to mitigate skin effect losses at high frequencies. Because of its ease of connection by soldering or clamping, copper is still the most common choice for most light-gauge wires. Aluminum has been used as a conductor in housing applications for cost reasons. It is actually more conductive than copper when compared by unit weight, but it has technical problems related to heat and its coefficient of thermal expansion, which tends to loosen connections over time. Conductor voltage The voltage on a conductor is determined by the connected circuitry and has nothing to do with the conductor itself. Conductors are usually surrounded by and/or supported by insulators and the insulation

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