Understanding AC Circuits

Unit 4

Transformers

Unit Introduction

Transformers are important electronic devices. They are used either to increase or to decrease alternating current (ac) voltage. Transformers are made with two separate sets of wire windings on a metal core. These are called the primary winding and the secondary winding. A transformer that increases voltage is called a step-up transformer; one that decreases voltage is called a step-down transformer.

Unit Objectives

Upon completion of this unit, you should be able to:

1. List several purposes of transformers.

2. Describe the construction of a transformer.

3. Explain transformer action.

4. Calculate turns ratio, voltage ratio, current ratio, power, and efficiency of transformers.

5. Explain the purpose of isolation ...