Primary Coil: The primary coil is the coil of wire in a transformer that receives the input voltage and current. It is connected to the power source.
Secondary Coil: The secondary coil is the coil of wire in a transformer that delivers the output voltage and current. It is connected to the load or device being powered.
Step-up Transformer: A step-up transformer increases the voltage from the primary coil to the secondary coil, resulting in higher output voltage.