Maintenance Technician Practice Test 2026 - Free Maintenance Technician Practice Questions and Prep Guide

The typical voltage for residential electrical systems in the United States is 120 volts. This standard voltage is used for most household appliances and lighting fixtures, making it the norm for residential electrical wiring.

In homes, the electrical systems are usually set up to distribute 120 volts through standard outlets, which accommodate various devices such as televisions, computers, and kitchen appliances. Additionally, larger appliances, like dryers and ovens, typically require higher voltages, such as 240 volts, but those are specifically catered to with dedicated circuits.

The reference to 110 volts is commonly considered in the context of historical standards but is effectively rounded up to 120 volts in modern practice. While 220 and 240 volts are utilized in specific applications, they do not represent the standard voltage supplied throughout residential homes for general use. This distinction highlights why the selection of 120 volts is correct in identifying the prevalent voltage for residential systems in the U.S.