Voltage Transformers

Voltage transformers are electrical devices designed to change the voltage value in a current without using any moving parts, only magnetic coils. A voltage transformer has a central core that is magnetic. This core is couple with tightly wound wire that is designed to either step up the voltage of step it down. This is accomplished by passing electric energy from one circuit to another through the magnetized core of the voltage transformer. The windings inside the voltage transformer are known as Primary and Secondary windings. When current passes through one winding, it creates an electromagnetic field that expands and collapses, thereby changing the induced current, which in turn creates an output charge in the secondary coil.

The term step up and step down actually refer to the input voltage of a voltage transformer. This means that if you are in America then you are using 120 Vac power (as is typically on the American continent) but when you travel to Europe you discover that all power outlets run at 220 Vac. In this case you need a step down transformer to lower the current voltage from 220 Volts to 120 Volts. Similarly, if you buy something in Europe or Asia and bring it back to America, you will need a step up voltage transformer to convert the local 120 Vac into 220 Vac to run your electronic equipment without frying it.

Voltage transformers are also used in high-tension power cables that carry electricity for miles, across cities, towns, and right into villages. Step up voltage transformers are used to boost the electric power as it leaves the power station. When the same electricity reaches it destination, a step down voltage transformer is used to convert the electricity back down to usable levels. This stepping up of power between sending and receiving power stations is done because when electricity travels for so many miles there is bound to be some leakage. It is best to send the power at a higher level and then step it down before sending it to the consumers rather than risk a system-wide crisis.

What is remarkable is that the voltage transformer is one of the simplest of electronic devices. The basic principles of it working have not changed in over a century even though the materials used in its construction have undergone much iteration. Both the consumer and the power suppliers benefit from the use of voltage transformers. A parallel exists in the world of telecommunications because taking a hint from the voltage transformer some individuals had used audio frequency transformers that eventually led to the modern telephone. You can find these audio frequency transformers in some electronic devices even today.

While power stations use huge voltage transformers the size of a small building, for most common equipment the voltage transformer can be as small a thumb-sized device or the size of a shoebox. It does not matter what the size of a voltage transformer is. They all work the same way except for working with different voltage levels.