A transformer uses electromagnetic principles to increase or reduce the voltage in a circuit. A typical transformer consists of a ring, or core, of iron with a coil of wire (called the primary winding) connected to a primary power source. A second coil of wire (the secondary winding) is wound through the "hole" in core around the opposite side.
When the primary winding is connected to an AC power source, it generates a magnetic field that pulses and changes direction with each alternation in current. The iron core focuses this magnetic field around the loop and induces a corresponding current in the secondary winding. As the number of turns on the secondary winding increases, the current decreases and voltage increases.
We can calculate exactly how much the voltage will be increased (stepped up) or decreased (stepped down) based on the ratio of turns in the secondary winding compared to the number of turns in the primary winding. If the secondary winding has twice as many turns as the primary winding, the voltage will be doubled. If the secondary winding has half as many turns, the voltage will be cut in half.
Example:
A primary winding with 200 coils and an input of 12 Volts will induce 60 Volts in a secondary winding with 1,000 turns. If the secondary winding has only 100 turns, it will produce only 6 Volts.
