For this extension cord wiring repair, all you need is a new plug!
ComplexityBeginner
Introduction
I'm an early riser, and I like to work in the yard. Rather than annoy my new neighbors with gas-powered lawn equipment, I invested in an electric lawn mower, and promptly ran over the extension cord. Thank goodness for circuit breakers! Extension cords aren't cheap, especially heavy-duty ones like the one I had just bought, imagining years of outdoor and garage shop use.
Not to worry. I'm an electrician, and I've mended my share of extension cords. You can, too, and I'll walk you through the process. For cords that are damaged close to an end, we'll chop off that end and add a new plug. If the damage is in the middle, congrats! You now have two (shorter) cords for the price of one. Don't try to splice an extension cord in the middle.
A couple of safety notes before we start: First, make sure you replace the plug with one that's the same rating as the cord. Second, make sure the plug is the same configuration (male or female) as the one you're replacing. Never make a cord with two male ends. You could seriously injure or even electrocute yourself or someone else. Finally, make sure the non-damaged end of the cord is unplugged before you start. Let's go!
Tools Required
- Lineman's or diagonal pliers (optional)
- Standard screwdriver
- Utility knife (optional)
- Wire strippers
Materials Required
- Screw-terminal replacement plug(s)
Project step-by-step (4)
Step 1
Prep the cord
- Examine the cord to find the damage and determine the best course of action.
- Cut the damaged part away using a wire stripper or cutting pliers.
- For cords damaged near the middle, cut out the damaged section to make two shorter cords.
- For cords damaged near either end, cut off the plug and damaged section from that end only.
- Remove about two inches of the outer jacket by carefully scoring around the circumference of the cord, then wiggling it back and forth.
- If you accidentally nick the inner wires, start over.
Step 2
Prep the plug
- Open the replacement plug by unscrewing the housing or popping out an insert, depending on the model.
- Loosen strain relief screws at the base of the plug, if present.
- Slide the cord through the strain relief and plug housing.
- Leave the housing loose for now.
- Tie the white and black wires into an underwriter’s knot if your plug does not have strain relief.
- Determine if you need to cut any length off the conductors by visualizing the distance to the terminal screws.
- When complete, the outer jacket must be completely inside the plug, with no individual conductor insulation sticking out.
- Loosen terminal screws on the replacement plug.
Step 3
Prep and attach the conductors
- Strip a half-inch to three-quarters of an inch of insulation from each wire with your wire strippers.
- You may need to strip more or less, depending on your terminal screw setup.
- Replacement plugs often have a strip gauge printed on the plug to assist.
- Trim the exposed wires if needed, and twist the strands into a tight point.
- Wrap wires clockwise around the terminal screws, keeping stray strands tucked under the screw, and tighten with a screwdriver:
- Black wire to brass screw.
- White wire to silver screw.
- Green wire to green screw, or screw that corresponds to the rounded ground prong.
- Alternatively, insert wires into terminal clamps, if present, and tighten them with a screwdriver.
- Tug on wires to make sure they are secure.
Step 4
Finish up
- Slide the housing up over the plug and tighten with a screwdriver.
- Tighten the strain relief around the outer jacket only. Do not restrict individual conductors.
- Make sure you can’t see any interior wires. If you can, undo the plug, trim the wires and re-attach.
Originally Published: December 14, 2018
