How to Wire a 3 Prong 220v Plug or Outlet

Maybe you bought a 3 prong dryer but your home electrical system is 120V, or you have a 3 prong electrical tool that you want to use.

You can still use the heavy appliances in your home by installing a 220V plug with 3 wires. 

A 3 prong 220-volt outlet wired to a 30 amp breaker can carry any of the power-hungry appliances, such as a dryer and large welder. 

However, it must be on a dedicated circuit and on a 10 gauge wire. Read on to learn how to wire a 220V plug with 3 wires.

Importance of wiring a 220-volt plug correctly

There are so many benefits of wiring a 220 volt outlet correctly, they include:

Personal safety: If the electrical wiring is correct, the chances of electrical hazards are reduced. Incorrect wiring in a 220v outlet can lead to electrical shock, burn and fire.

Electrical safety: Correct wiring ensures current flows safely along the circuit and appliances without leakage. It also reduces the risk of ground faults, power surges and damage to electrical devices

Compliance with NEC code: In many countries, wiring regulations are in place to ensure electrical safety and comply with national and international standards. Wiring a 220V plug correctly is a legal requirement and failure to comply may lead to fines or other legal penalties.

Energy efficiency: Proper wiring can also reduce energy waste and thus lower your electricity bills. 

Tools and materials required for the installation.

The following tools and materials will be necessary to wire the plug.

  • Wire cutter or stripper: This tool will help you cut off the big plug so you can install a new one. You can also use a wire stripper to remove the insulators covering the wire strands.
  • Screwdriver: The screwdriver will help you loosen the plug screws so you can do the wire connection.
  • Three-prong 220 plug: get a normal sized plug that will fit into the socket. A two-prong plug or three will be ok depending on the structure of your socket.
  • Utility knife: This is the knife you will use to cut and open the wire insulation or coat.

How to wire a 220V plug with 3 wires

If you already have a 220 outlet in your home, all you will do is to change it to a 3-prong plug. Else, consider running a dedicated 220-volt circuit connected to a 30 amp breaker. 

Here is a guide on how to install the 30 amp breaker.

Once you are through with that, you can move on with the next steps.

Step one: Turn off the power source

Before embarking on any installation, it is wise to turn off the breaker. This is to make sure that the circuit is dead and could not lead to electrocution when you touch it.

The circuit breaker is usually installed inside the main breaker panel, and you can switch it off by flipping the breaker to the off position.

Step two: Test the outlet with a multimeter.

After turning off the breaker, confirm that the outlet is off with your multimeter.

You can do that by inserting the two probes of your multimeter in the ports of the outlet. The reading should be zero to proceed to the next step.

Step three: Remove the old outlet

Using your screwdriver, loosen the screws and remove the old outlet. But if you don’t have a 220 v power system before, you will first install a metal box before mounting the 220-volt plug.

Step four: Identify the wires

The modern 220v outlet usually comes with 4 wires, two hot wires (black and red), one neutral (white wire) and a ground wire (green).

But since we are wiring a 3 prong outlet, we will make use of three wires, the green, red and black wire.

The neutral wire should be disconnected from the breaker board.

Step five: Connect the stripped wires to the new outlet

  • Attach the green wire (ground) to the ground terminal, which is usually the green screw on the plug
  • Connect the black (hot wire) to any of the brass terminal screws
  • Attach the red wire to the other terminal

Step six: Secure the wires

  • Tighten the terminal screws, ensuring that the wires are tight
  • Make sure there are no loose or exposed wire ends that could cause a short circuit

Step seven: Mount the outlet

Once you are through with the connection, mount the outlet in the metal box and tighten it. Cover the faceplate and tighten the screws. 

Test the plug

Once you have finished wiring the plug, switch on the power supply and test the outlet. Use a multimeter to make sure that the plug is working fine.

Related article: How to Wire a 220v Plug with 4 Wires


Wiring a 220V plug with three wires is easy for electricians but can be hard DIY and homeowners. Always follow safety precautions such as wearing your glove and turning off the power supply before working with electricity.

If you are not confident in your ability to wire the plug correctly, call an electrician.

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About mariaelectricals

Hi, I am Emmanuel Nwankwo, a commercial electrician and the founder of I established this blog to share my decades of work experience in electrical installations and repairs.