Take the Worries and Confusion Out of your Home Wiring. All your Electrical Related Questions can be Answered here


Changing A 220 Volt Receptacle From 3-wire To 4-wire

July 5, 2006

Q: I have a three prong, 220 volt outlet with only three wires that I want to convert to a four prong outlet. You mentioned that I need to run a new 3 conductor cable with ground to install the four prong outlet. How exactly do I do this?

A: It is difficult to tell you how to install the new cable without seeing your place. Basically you need to run this cable from your electrical panel to the receptacle (outlet) location. You can either run your wire up and through an attic space or go down through an unfinished basement or crawl space. Home Depot has a good book about this.

You need a connector on each end of the wire where it enters the panel and receptacle box. You need to staple your wire within 12 inches of the connector and every three feet thereafter for support.

Your wire size depends upon the load being served. 12/3 copper with ground is rated for 20 amps, 10/3 copper with ground is rated for 30 amps, 8/3 copper with ground is rated for 40 amps.

Remember safety first when working with electricity. Be sure to turn off the power and verify that the power is off using a volt meter before beginning any work.

Technorati tags: | | | | |

DIY Electrical Wiring Help from a Master Electrician Do you need assistance with your electrical wiring project? Please visit my DIY Electrical Wiring Help from a Master Electrician page. Where I provide electrical wiring tips, expert electrical advice, answers to your electrical questions and electrical consulting & design services over the phone, via instant messenger or via email.

If you enjoyed this post, make sure you subscribe to my RSS feed or receive updates via email. You can also follow me on Twitter and "LIKE" me on Facebook.

Similar Posts:
Site Sponsor


2 Responses to “Changing A 220 Volt Receptacle From 3-wire To 4-wire”

  1. Paul Rosmann on December 18th, 2008 5:07 pm

    I am replacing an old electric stove (3-wire 220) with a new duel fuel stove with an electric oven (4-wire 220). Does this mean that I have to go all the way back to the panel with another wire, or can the ground and neutral be the same wire? In other words, can the three wire ground serve as both ground and neutral to install a 4-wire receptacle?

  2. jeremy on February 8th, 2012 7:44 pm

    I recently bought an HE washer and dryer. The wire from my panel has three wires and an exposed copper wire. I clipped it down and taped it off. the oulet that was connected to this wire was 4 prong but was exposed, no case on it. I replaced with a 4 prong with a case, we have never had a problem with this set up before, should i be concerned.