How to Replace a Worn-Out Electrical Outlet – pigtail wiring connections, install and test the outlet with a receptacle tester. The replacement electrical outlet was backwired in series in How to Replace a Worn-Out Electrical Outlet – Part 2
Electrical Outlet Pigtail Wiring Connections
I prefer wiring middle-of-run outlets in parallel with pigtail connections for improved reliability and fault isolation as illustrated in following the wiring diagram. Some local building codes require outlets to be wired in parallel for these reasons.
Rewiring an outlet from series to parallel is straightforward with two short lengths of wire and wire nuts for the hot and neutral pigtail connections. A pigtail connection is always used for middle-of-run ground connections whether wired in series or parallel.
Shut off the Electricity
Be certain to shut off the electricity at the circuit breaker panel as described in Part 1 if you haven’t already done so.
Wiring an Electrical Outlet in Parallel
To demonstrate wiring an outlet in parallel, I disconnected the new Leviton 5252 heavy duty replacement outlet which was backwired in series in Part 2. That’s the neat thing about backwiring – it’s easy to install and disconnect the wires just by loosening the terminal screws.
An electrical is wired in parallel with pigtails by:
- Cut a 6″ inch length of black (hot) and white (neutral) wire for the pigtail splices.
- Strip 3/4″ inch of insulation the wires in the wall box and one end of the pigtail splice.
- Matching wire colors, twist the ends of the two black wires coming from the outlet box together with the 6″ black wire splice with lineman’s pliers. Twist the wires in a clockwise direction (right twist) with lineman’s pliers as shown. Secure the wires with a wire nut.
- Repeat the pigtail splice connection for the white (neutral) wires.
Note the bare ground wire is already on a pigtail connection via a metal bonding clamp. If you happen to be running wire to install a new middle-of-run outlet, be certain to make a pigtail connection for the ground wires.
Pigtails wire connections are complete:
Use the strip gauge on the back of the electrical outlet to measure and strip the correct length of wire for the backwire connection.
The ground wire is looped around the green ground screw. Tighten the screw really well to secure the connection.
Backwire the outlet by:
- Loosening the side screw to expand the internal clamp.
- Insert the black (hot) wire in one of the backwire holes on the side with the brass color screws. Any of the four backwire holes will do. Take care the wire is inside the jaw of the metal clamp.
- With the wire fully inserted, tighten the side screw to clamp the wire in place.
- Insert the white (neutral) in a backwire hole on the side with the silver screws and secure it by tightening the screws as before.
- Check the wires are secure by giving the wires a pull. The wires should be held fast with no “give” or rotation.
Carefully fold the wires into the electrical box using gentle loops. 12 gauge wire is much stiffer than 14 gauge and getting all the wires folded in can take some attention to detail. Make sure the bare ground wire is not touching the side screw terminals.
When the wires are in the box, mount the outlet to the wall box with the two mounting screws.
The old outlet wallplate will be replaced with a Leviton Nylon Wallplate for a new and neat appearance.
A “GFCI Protected Outlet” sticker is affixed to the wallplate (you get these when you purchase a GFCI outlet – I had some left over from the basement bathroom project).
The receptacle shown in the above photo doesn’t have the GFCI test button. I later purchased GFCI receptacle tester: plug it in, press the small button and it’ll create a “safe ground fault” to trip the GFCI and shutoff power to the circuit. That way you know the GFCI outlet (not shown) or GFCI circuit breaker is working correctly. Of course, you’ll have to press the Reset button on the GFCI outlet or reset the GFCI circuit breaker after testing the outlet.
I turned on the circuit breaker at the main electrical panel and verified the outlet is correctly wired with the receptacle tester. Everything is correct.
Worn-Out Electrical Outlet Teardown
The old electrical outlet that was getting worn out with loose plugs is a Leviton Residential Grade Electrical Outlet, Model #: 5320-WCP. The outlet served well by bathroom vanity for about 10 years before wearing out. For 59 cents, it’s a testament to the success of mass production and maximum quality at a low price.
A new and old Leviton 5320-WCP receptacles are shown here for comparison. Some pitting around the receptacle face can be seen on the old outlet.
The old receptacle is held together by two metal rivets on the back. I cut off the rivet heads with a Dremel tool cutoff wheel.
The main problem with the old receptacle is it wasn’t holding a plug because the U-shaped contacts (yellow arrows) were getting worn out. These U-shaped contacts – also called “wipes” – fatigue and open up over time through repeated use when plugging in appliances.
As the contacts open up, the plug becomes loose resulting in a high resistance connection, causing overheating, arcing and corrosion. If the outlet isn’t replaced, the connection can become so bad that constant a constant sizzling or hissing noise is heard from the electrical arcing as happened with that outlet I described in Part 1.
Be safe,
Bob Jackson
