What is the purpose of a transformer?
Transformers are found everywhere Alternating Current (AC) electrical energy is used. A transformer is an electrical device that trades voltage for current in a circuit, while not affecting the total electrical power. This means it takes high-voltage electricity with a small current and changes it into low-voltage electricity with a large current, or vice versa. One thing to know about transformers is that they only work for Alternating Current (AC), such as you get from your wall plugs, not Direct Current (DC).
Transformers can be used either to increase the voltage also known as stepping up the voltage, or they can decrease the voltage also known as stepping down the voltage. Transformers use two coils of wire, each with hundreds or thousands of turns, wrapped around a metal core. One coil is for the incoming electricity and one is for the outgoing electricity. Alternating Current in the incoming coil sets up an alternating magnetic field in the core, which then generates Alternating Current in the outgoing coil.
Energy is lost in the process of transmitting electricity long distances, such as during the journey from a power plant to your home. Less energy is lost if the voltage is very high. Usually, electrical utilities use high voltage in long-distance transmission wires. However, this high voltage is too dangerous for home use. In the case of electrical utilities in homes, they use transformers to change the voltage of electricity as it travels from the power plant to your home.
First using a transformer, the voltage of electricity coming from a power plant is “stepped up” to the right level for long-distance transmission. Because high-voltage current can arc, step up transformers called ignition coils are used to power spark plugs. Dynamos at power plants generate large currents but not a lot of voltage. This electricity is stepped up to high voltage for transmission over wires, as electricity travels more efficiently at high voltage.
Later, the voltage is stepped down before it enters your home – once again using transformers. A “step-down” transformer changes the 440-volt electricity in power lines to the 120-volt electricity you use in your house. Then, the current is either used at that level for devices like light bulbs, or it is converted to DC using an AC/DC adapter for devices like laptop computers.
Since the emergence of the first constant-potential transformers in 1885, transformers have become essential for the transmission, distribution, and utilization of Alternating Current electrical energy in all applications of power. At Power Temp Systems, we specialize in making innovative equipment that efficiently and safely distributes and utilizes power for any project.