A 2:1 step-down transformer has twice as many primary windings as the secondary coil does. This means that if you apply 12V and 12A to the primary winding, approximately 6 V AC will be induced into the secondary winding, however, the output amperage will be doubled to 24 amps.

Do transformers change amperage?

So when a transformer increases voltage, it decreases current. Likewise, if it decreases voltage, it increases current. But the power remains the same. All transformers have two coils of wires called the primary and secondary.

How does a transformer affect amperage?

A transformer transfers power from the primary coil to the secondary coil. Since the power must stay the same, if the voltage increases, the current must decrease. Likewise, if the voltage decreases, the current must increase.