First, a very important safety warning. If you don’t feel comfortable working with electricity, don’t attempt this project. That goes for any kind of project, but especially projects that can seriously hurt or kill you or others. Below, I’m going to show the steps I took to repair an extension cord. (I’m not a licensed electrician. I’m just someone who has studied electricity and has been shown the basics by a couple of electricians.) Instead of attempting to do a repair like this one, you may be better off buying a new extension cord or getting a professional to do the repair for you.
About 10 years ago, I picked up this electrical cord at a yard sale for $2. At that time, there was a big gash near one end. Instead of splicing it, I just shortened it from 100 feet to 92 feet and added the connector end you see below. This kind of repair connector costs around $8 to $10. Recently another tear developed, so I decided to to repeat the process and take a couple of feet off it. (A 90 foot, or 30m extension cord is still very long.)
Taking apart the “well used” repair connector, you can see that it is in three parts. Two outer shell pieces and a central core that holds the wires.
After using my lockout, I started off by using an knife to cut the cords outer insulation. I was careful not to cut the inside three wires. I left about 1.5″ (or 38mm).
I used the same knife to cut away the white filament. (It isn’t needed, it just gets in the way.)
A wire stripper removed about 3/8″ (10mm) from the black, white and green wires wires.
On the central core piece of the connector, there are three colour coded screws. The white wire goes under the “chrome” coloured screw, the black wire goes under the “brass” coloured screw and the green wire goes under the green colour screw. I used a square drive (#1 or “green Robertson”) screwdriver to tighten them.
The final assembly step was to snap the outer shell pieces together and use the same screwdriver to tighten the two outside screws.
Finally, I tested the extension cord; everything seemed fine.