Electrical Fundamentals for Appliance Technicians
Residential voltage systems, electrical measurements, Ohm's law, capacitors, and safe testing procedures for Canadian appliance service technicians.
- Identify the typical operating voltage for residential appliances in Canada
- Explain the function of GFCI protection and where it is required
- Describe how to measure voltage, current, and resistance using proper instruments
- Explain the purpose of start and run capacitors in appliance motors
- Apply Ohm's law to diagnose appliance electrical circuits
Lesson 1
Canadian Residential Voltage Systems
Understanding Residential Power
Every appliance technician in Canada must understand how electrical power is delivered to residential homes. Canadian homes receive power from the utility company through a service entrance that provides a 120V/240V split-phase supply. This is the typical operating voltage for residential appliances in Canada and a fundamental fact you must know for the Red Seal exam.
How Split-Phase Power Works
The utility transformer delivers two hot legs (L1 and L2) and one neutral. Each hot leg provides 120V to neutral. Between L1 and L2 you get 240V. Small appliances like refrigerators, microwaves, and dishwashers operate on 120V. Large appliances like electric ranges, dryers, and some cooktops require 240V.
Voltage Ranges by Appliance Type
| Appliance | Voltage | Typical Circuit |
|---|---|---|
| Refrigerator | 120V | 15A or 20A |
| Dishwasher | 120V | 20A dedicated |
| Microwave | 120V | 20A dedicated |
| Electric Range | 240V | 40A or 50A |
| Electric Dryer | 240V | 30A |
| Washing Machine | 120V | 20A |
| Garbage Disposal | 120V | 15A or 20A |
Exam Tip
The exam may use terms like "110V" or "220V" as distractors. The correct answer for Canadian residential power is always 120V/240V split-phase. Three-phase power (220V or 480V) is used in commercial and industrial settings, not residential.
The typical operating voltage for residential appliances in Canada is 120V/240V split-phase. Small appliances use 120V, large appliances use 240V, and three-phase power is not used in residential settings.