BOOK_CONTENT
From Electrical Equipment Handbook: Troubleshooting and Maintenance

A transformer is a device that uses the action of a magnetic field to change ac electric energy at one voltage level to ac electric energy at another voltage level. It consists of a ferromagnetic core with two or more coils wrapped around it. The common magnetic flux within the core is the only connection between the coils. The source of ac electric power is connected to one of the transformer windings. The second winding supplies power to loads. The winding connected to the power source is called the primary winding or input winding. The winding connected to the loads is called the secondary winding or output winding.

IMPORTANCE OF TRANSFORMERS

When a transformer steps up the voltage level of a circuit, it decreases the current because the power remains constant. Therefore, ac power can be generated at one central station. The voltage is stepped up for transmission over long distances at very low losses. The voltage is stepped down again for final use. Since the transmission losses are proportional to the square of the current, raising the voltage by a factor of 10 will reduce the transmission losses by a factor of 100. Also, when the voltage is increased by a factor of 10, the current is decreased by a factor of 10. This allows the use of much thinner conductors to transmit power.

In modern power stations, power is generated at 12 to 25 kV. Transformers step up the voltage to 110 to 1000 kV...

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Products & Services
Transformer Winding Services
Transformer winding services design transformers and other magnetics products for application-specific and OEM usage in a variety of industrial, medical, military, aerospace, telecommunications, commercial and specialty applications. 
Board Mount Transformers
Board mount transformers are transformers designed to be embedded in or mounted on computer boards.
Power Transformers
Power transformers convert power-level voltages from one level or phase configuration to another.  They can include features for electrical isolation, power distribution, and control and instrumentation applications.
Electrical Coil Winding Machines
Electrical coil winding machines are used to wind coils for motors, transformers, inductors and chokes.
Flyback Transformers
Flyback transformers (FBT) or line output transformers (LOPT) are designed to produce a very high voltage by storing energy in their magnetic windings.

Topics of Interest

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