Nate Electrical Practice Exam 2026 - Free Electrical Practice Questions and Study Guide

The primary role of a transformer in electrical systems is to change voltage levels. Transformers are devices that transfer electrical energy between two or more circuits through electromagnetic induction. They can step up (increase) or step down (decrease) voltage while maintaining the overall power level, minus losses due to efficiency.

Transformers achieve this by using coils of wire wrapped around a magnetic core; when alternating current flows through one coil (the primary winding), it creates a magnetic field that induces a voltage in the second coil (the secondary winding). This functionality is essential in various applications, such as power distribution, where high voltages are used to minimize energy loss over long distances before being transformed to lower, usable voltages for consumers.

This role is critical for ensuring that electrical energy is transmitted efficiently from power plants to homes and businesses, where it can be used safely at suitable voltage levels.