Red Seal Construction Electrician Practice Exam

What is the typical voltage supply provided in residential wiring?

1. 240 volts

2. 120/240 volts AC

3. 480 volts

4. 110 volts

The correct answer is: 120/240 volts AC

In residential wiring, the typical voltage supply is 120/240 volts AC. This means that most residential electrical systems are designed to provide both 120 volts and 240 volts, depending on the needs of the appliances and circuits. The standard 120 volts is commonly used for general-purpose outlets, lighting, and most household devices, while the 240 volts is typically available for larger appliances such as dryers, ovens, and air conditioning units that require a higher voltage to operate efficiently. This dual voltage supply allows for versatility in powering both standard and high-demand equipment within a typical home. In North America, the 120/240 volt system is split-phase, which allows for the use of a transformer to derive both voltages from the same supply line, providing convenience and adaptability for various electrical requirements.