What type of transformer is identified when the number of turns is greater on the primary side compared to the secondary side?

The transformer identified when the number of turns is greater on the primary side compared to the secondary side is a step down transformer. This type of transformer is designed to reduce voltage levels. As the primary coil has more turns than the secondary coil, it steps down the voltage from the primary side to the secondary side while also increasing the current, conforming to the principle of conservation of energy.

Typically, in a step down transformer, the voltage reduction is inversely proportional to the turns ratio. Therefore, if the primary has more turns, the output voltage from the secondary will be lower than the input voltage on the primary. This principle is essential for applications where it is necessary to lower voltage for safe usage in household appliances or for specific electronic devices.

The other transformer types mentioned serve different functions: a step up transformer increases voltage; an isolation transformer keeps the input and output electrically separated while maintaining the same voltage level; and an auto transformer has a single winding that acts as both the primary and secondary, often being used for more specialized applications.