How to Repair an Extension or Power Cord

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How to repair an extension cord plug or power cord on an appliance.

There are many times when we go to reach for an extension cord and find that it is twisted, has a split jacket, or the prongs are bent or missing. The goes for appliances such as vacuum cleaners where the cord is stretched around corners, closed in doors, or pulled out of receptacles during use. Using damaged extension or power cords can lead to serious injury, fires, or damaged equipment. Follow these simple steps to replace a socket or plug on an extension cord or power cord for appliances. Your cord will be safer and you’ll save money and headaches in the long run.

As the price of copper has increased, so has the cost of extension cords. You can repair a damaged cord for about $5. You can also shorten longer cords that have been twisted and crimped. Twisting the wires can lead to hot spots that can melt the cord or lead to shorts that can shock the user or trip a breaker.

Tools and Materials

Flat and Philips screwdriver

Utility knife

Wire stripper/cutter

New plug or socket

Replacing an extension cord plug

Wire a pair of wire cutters or lineman pliers, cut off the damaged end of the cord.

1. Remove the cord jacket

Make a shallow cut down the length of the cord through the outer jacket; then carefully score around the cord until you can break the PVC jacket off.

2. Strip the wires

Cut and strip the wires to the length indicated in the strip gauge or the plug, leaving as much of the outer jacket as possible. Note: Remember to use the same style of plug; don’t make a cord with 2 female or 2 male ends.

3. Completing the Connections

Extension and power cords use stranded copper wire so it is important that you twist the wire so that all of the strands are beneath the terminal screws. The black wire is inserted in the terminal with the brass screw; the white wire goes to the silver screw; the green ground wire to green screw. Note: The wider prong of the plug is always the white (neutral wire).

Separate the wires and screw them into place. It can be difficult to work with heavy 12-gauge wire, but the more of the jacket you can leave inside the plug, the less likely it is to pull out of the plug clamp and expose the internal wires.

Close the plug and screw it together tightly so the cord is locked in. Some repair plugs have a gasket with a curved side for heavy cords while other types use screws to hold the cord in place.


Make sure you use the proper size plug or socket for your cord. Standard 15-Amp cords use NEMA 5-15R or 5-15P (R is for receptacle, or socket for cords, and P is for plug)

Do not connect extension cords in series.

Extension cords or plugs should bear the Underwriters' Laboratory (UL) mark.

Extension cords should not be tacked, stapled or affixed in some temporary or permanent manner.

Major appliances should not be permanently connected to a receptacle with an extension cord.

If you are using an extension cord in a wet location, plug it into a GFCI receptacle or use a GFCI extension cord or plug adapter.

Do not cover extension cords with carpeting, plywood, or some other combustible material.



Posted on Jan 10, 2011
Jerry Walch
Posted on Jan 5, 2011