120 Volt Outlet Wiring Diagram

Are you planning to install or replace an electrical outlet in your home, but don’t know where to start? Understanding the wiring diagram is the first step in the process. In this article, we’ll explain the basics of wiring a 120-volt outlet and provide a step-by-step guide to help you complete the project.

The Basics of Electrical Outlets

Electrical outlets are used to provide power to various devices and appliances in a home. There are different types of outlets, including 120-volt outlets, which are the most common type.

A 120-volt outlet is typically rated for a maximum of 15 amps and is designed to supply power to smaller household items such as lamps, chargers, and small appliances. It is important to ensure that the outlet is wired correctly to avoid electrical hazards such as short circuits, fires, and electrocution.

Components of a 120-Volt Outlet

Before diving into the wiring process, it is important to understand the different components of a 120-volt outlet.

Component Description
Outlet Box The metal or plastic box that holds the outlet and protects the wiring from damage.
Outlet The receptacle that the device plugs into.
Wiring The electrical wires that supply power to the outlet.

Step-by-Step Guide to Wiring a 120-Volt Outlet

Step 1: Turn off the Power

Before starting any electrical work, ensure that the power is turned off at the circuit breaker. This will prevent electrocution and damage to the electrical components.

Step 2: Choose the Correct Wiring

There are different types of wiring, including copper and aluminum. Copper wiring is the most common and is recommended for 120-volt outlets.

Step 3: Strip the Wires

Using a wire stripper, remove the outer insulation of the wires to expose the copper wire. The amount of wire to be stripped will depend on the length of the wire and the size of the outlet box.

Step 4: Connect the Wires to the Outlet

Connect the black (hot) wire to the brass-colored screw on the outlet and the white (neutral) wire to the silver-colored screw. The green (ground) wire should be connected to the green screw or the back of the outlet box if there is no green screw.

Step 5: Install the Outlet Box

Attach the outlet box to the wall, ensuring that it is level and flush with the surface. Use screws to secure the box in place.

Step 6: Attach the Outlet

Insert the outlet into the box and secure it with screws. Ensure that the outlet is level and flush with the surface.

Step 7: Test the Outlet

Once the outlet is installed, turn on the power at the circuit breaker and test the outlet using a voltage tester. Ensure that there is power to the outlet before using it.


Q: Can I use aluminum wiring for a 120-volt outlet?

A: While aluminum wiring is still used in some electrical systems, it is not recommended for 120-volt outlets. Copper wiring is the preferred choice due to its conductivity and durability.

Q: Can I wire a 120-volt outlet without an outlet box?

A: No, it is not safe or recommended to wire an outlet without an outlet box. The outlet box protects the wiring from damage and provides a safe enclosure for the electrical components.

Q: How do I know if I wired the outlet correctly?

A: To ensure that the outlet is wired correctly, use a voltage tester to test the outlet before using it. If the tester indicates that there is power to the outlet, then it has been wired correctly.

Q: Can I install a 120-volt outlet in a bathroom?

A: Yes, but it must be a GFCI (ground-fault circuit interrupter) outlet, which is designed to protect against electrical shocks. It is also recommended to have a licensed electrician install the outlet in a bathroom due to the risk of electrical hazards in wet areas.

Q: Can I wire multiple 120-volt outlets together?

A: Yes, but it is important to ensure that the wiring is designed to handle the load of multiple outlets. It is recommended to consult a licensed electrician for guidance on wiring multiple outlets in a circuit.

Overall, wiring a 120-volt outlet can be a straightforward process with the right tools and knowledge. By following the steps outlined in this article, you can safely and confidently install or replace a 120-volt outlet in your home.