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Transformers are often used in electrical circuits to change the voltage of electricity flowing through a circuit.
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Image courtesy of Wikipedia (modified by Windows to the Universe staff).

The Role of Voltage Transformers in Our Electric Power Systems

Transformers are pieces of equipment used in electrical circuits. Transformers change the voltage of electricity flowing in the circuit. Transformers can be used either to increase the voltage (called "stepping up") or decrease the voltage ("step down").

When electrical energy travels long distances in wires, some of the energy is lost. This happens to electricity during the journey from a power plant to your home. Less energy is lost if the voltage is very high, so electrical utilities use high voltage in long-distance transmission wires. However, this high voltage is too dangerous for home use. Electrical utilities use transformers to change the voltage of electricity as it travels from the power plant to you. First, the voltage of electricity coming from the power plant is "stepped up" using transformers to the right level for long-distance transmission. Later, the voltage is stepped down before it enters your home - once again using transformers.

Last modified February 25, 2009 by Randy Russell.

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