Repairing an electrical plug can seem like an average home repair, but care must always be taken when working with electrical cords and electricity. Electrical cords or extension cords are very prone to wear and tear, as the prongs get bent or broken off. The key is to match the replacement plug with the existing one. If the plug has one prong or blade slightly larger then the other, it is polarized and must be replaced with a polarized plug. Additionally, check if you need a two- or three-prong plug. Following a few steps will help you know how to wire electrical plugs correctly.
Disconnect the cord from any outlets or power sources.
Locate the end of the cord with the bad plug. Using the wire cutters, cut the plug off the cord.
Cut down the center of the two wires on a two-wire plug and split them apart. Use a utility knife. Using your fingers, pull the wires apart about 2 inches. For a three-wire cable, use the utility knife to cut about 2 inches of the outer sheathing off. Be careful to not cut to deep and cut the interior three wires. Cut the sheathing away to reveal three wires inside: black (hot), white (neutral), green (ground). Using the wire strippers, strip about 1 inch of insulation from each wire.
Remove the screws on the end of the new plug and open up the case on the plug to reveal the screws to the prongs inside.
Connect one wire to each of the two prongs and tighten to a snug fit with a screwdriver. For a three-wire plug, use the screwdriver to connect the black wire to the brass screw, the white wire to the silver screw, and the green wire to the remaining screw. Tighten each screw to a snug fit.
Replace the cover over the plug and tighten the screws to secure the cover on the end of the plug with the screwdriver.