Electrical Components - Pearson

← Back to document page

564 Electrical Components UNIT 36 OBJECTIVES After completing this unit, you will be able to: 1. determine the resistance value of a color-banded fixed resistor. 2. provide examples of where and how transformers are used. 3. identify paper and film, electrolytic, ceramic, and mica capacitors . 4. identify the different types of thermostats. 5. explain cut-in, cut-out, and differential on pressure switches. 6. test transformers, capacitors , contactors, and relays. 7. list the different types of fuses and overloads. 8. explain the difference between relay logic and solid-state logic. 9. describe how a silicon rectifier operates. INTRODUCTION Most HVACR service work deals with Electrical problems. These problems can be caused by component failure, im-proper installation, or misuse. It is therefore important that HVACR technicians have a thorough and complete under-standing of Electrical Components and wiring diagrams.

Capacitors can be roughly checked by using an ohm-meter. The ohmmeter used in testing capacitors should be able to read a high resistance and have at least an R * 100 scale. To test the capacitor, disconnect it from the wiring and place the ohmmeter leads on the terminals, as shown in Figure 36-15 .

  Resistance, Capacitors