How to Wire a 120-Volt 20-Amp Outlet

Installing a new 120-volt 20-amp electrical outlet is a straightforward project that I can tackle in a few hours. With proper planning and by following important safety precautions, I can upgrade my home's electrical system to add more outlets where needed.

Safety First When Working with Household Electricity

Whenever I work with electrical wiring, safety is the top priority. Electrocution is a real risk, so I make sure to:

• Turn off the main circuit breaker before starting any electrical project. This cuts power to the wires I'll be working on.
• Test wires with a non-contact voltage tester to confirm power is off.
• Wear insulated gloves and safety goggles for added protection.
• Never work on live wires. De-energize wires by turning off the circuit breaker first.

I avoid distractions and give the project my full attention. Rushing can lead to mistakes and shock hazards.

Choosing the Right Location

I select the outlet location carefully to ensure I can safely route the new wiring. Key factors include:

• Studs - Outlets must be securely mounted to studs in the wall for safety and stability. I locate the studs and choose a spot between them.
• Existing wiring - Running the new wires from the breaker to the outlet is easiest when I can access the wall cavity. Basements, attics and garages often work well.
• Convenience - I consider where the outlet is most useful, like near countertops or above furniture. Extension cords shouldn't be necessary.

Avoiding joints or splices as I run the cable keeps the wiring simple.

What You Need

• Cable ripper or drywall saw to cut drywall opening
• Voltage tester to confirm power is off
• Insulated gloves for safety
• Safety goggles to protect eyes
• 120-volt 20-amp circuit breaker
• 12/2 NM cable (12 gauge wire with black, white and ground wires)
• Electrical box sized for NM cable being used
• Cable clamps and wire nuts
• Neutral bonding screw or strap
• Wall plate matched to the electrical box size

I make sure to get the proper cable size and circuit breaker amperage for a 20-amp outlet.

Step-by-Step Installation Guide

With planning and safety preparations complete, I can move on to installing the outlet:

1. Turn Off Power

I turn off the main breaker and test that power is off in the work area for safety. I verify the outlet is deactivated by plugging in a lamp and checking that it does not turn on.

2. Cut Hole for Outlet Box

Using a drywall saw, I cut a hole at my desired location to mount the electrical box. I align the hole between two studs so the box can be screwed firmly in place.

3. Route Cable from Breaker to Outlet

I route the NM cable from the 120-volt 20-amp breaker in the panel to the outlet box. No splices should be made as I pull the cable through the open wall cavity.

4. Secure Outlet Box in Wall

I position the electrical box in the opening and screw it securely to the studs using mounting tabs on the box. At least 1/2" of the box should protrude from the wall.

5. Connect Wires

With no slack or kinks, I insert the cable and connect the wires:

• Green or bare ground wire to green screw or ground bar
• White neutral wire to silver screws
• Black hot wire to brass screw

6. Attach Neutral Bonding Screw

I attach a pigtail wire from the neutral screw to the neutral bonding screw in the box. This bonds the neutral and box for safety.

7. Mount Device and Wall Plate

I screw the outlet to the box, then install the matching wall plate to complete the job. The new 20-amp, 120-volt outlet is ready for use.

8. Turn Power Back On

Finally, I turn the main breaker back on, switch any local breakers back to the "On" position, and test my work. The outlet should function properly.

Call an Electrician for Large or Complicated Projects

For whole home rewiring or service panel upgrades, I leave the work to professional electricians. They have the experience to handle large-scale electrical projects safely. I focus my DIY skills on simpler jobs like swapping out outlets and switches.

With good planning and basic electrical understanding, installing my own 120-volt 20-amp outlet can save money while improving my home. By following critical safety steps and local electrical codes, I can take on basic upgrades with confidence.