Text: The actions of a transformer is determined by the way they are wound. If the secondary winding has more turns than the primary it will increase the voltage and decrease the amperage. Just how much it does this depends in the difference in the number of turns in secondary winding. If you have less turns in the secondary winding then it will lower the voltage and increase the amperage. A transformer can be wound with one primary and then several secondary winding of different lengths and you will have different voltages coming off the secondary according to the number of turns in each winding. You can also tap into the secondary winding at different points and get different voltages. One example of this is what they call a center tapped that is used in some AC to DC power supplies. One I have used in building power supplies is a 28 volt primary input and is center tapped where you have two 14 volt outputs. The step up or step down transformer use an iron core to transfer the flux rings from the primary winding to the secondary. This is because the windings are different length but the one I am talking about trying could be air core because the windings would be the same length. That way the primary winding would be running right beside the secondary winding and injecting the flux rings directly into the secondary winding.

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