The Best Way to Label and Test Breaker Switches
Plug a radio into an outlet to see what breaker switch controls the outlet.
Listen to your favorite music while solving a key DIY problem
I like to have my switches and outlets labeled, so it’s easy to figure out which breaker to shut off when I need to change a switch or outlet. When I moved into a new home, so I had to label everything. I didn’t have a helper, so I used a radio instead. I’d just plug it into an outlet and blast some music. Then, I’d flip breakers until the radio shut off. I had everything labeled in an hour. – Collin Grace
Making Connections Outside Electrical BoxesMistake: No electrical box | Never connect wires outside of electrical boxes. Junction boxes (or a J box) protect the connections from accidental damage and contain sparks and heat from a loose connection or short circuit. Solution: Add a box | Where connections aren't contained in an electrical box, install a box and reconnect the wires inside it. The photo shows one way to do this for an exterior light mounted on wood siding.
Cutting Wires Too ShortMistake 2: Wires too short | Wires that are cut too short make wire connections difficult and—since you're more likely to make poor connections—dangerous. Leave the wires long enough to protrude at least 3 in. from the box. Solution: Extend wires | If you run into short wires, there's an easy fix. Simply add 6-in. extensions onto the existing wires. The photo shows a type of wire connector that's easier to install in tight spots. You'll find these in hardware stores and home centers.
Leaving Plastic-Sheathed Cable UnprotectedMistake: Unprotected cable | It's easy to damage plastic- sheathed cable that's left exposed between framing members. That's why the electrical code requires cable to be protected in these areas. Cable is especially vulnerable when it's run over or under wall or ceiling framing, as shown here. Solution: Install a 2 x 2 | Protect exposed plastic- sheathed cable by nailing or screwing a 1-1/2-in.-thick board alongside the cable. You don't have to staple the cable to the board. Running wire along a wall? Use metal conduit.
Poor Support for Outlets and SwitchesMistake: Loose outlet | Loose switches or outlets can look bad, but worse yet, they're dangerous. Loosely connected outlets can move around, causing the wires to loosen from the terminals. Loose wires can arc and overheat, creating a potential fire hazard. Solution: Add rigid electrical box spacers | Fix loose outlets by shimming under the screws to create a tight connection to the box. You can buy special spacers like we show here at home centers and hardware stores. Other options include small washers or a coil of wire wrapped around the screw. Add some insulation while you're back there, too.
Installing a Three-Slot receptacle without a Ground WireSolution: Install a two-slot outlet | If you have two-slot outlets, it's tempting to replace them with three-slot outlets so you can plug in three-prong plugs. But don't do this unless you're sure there's a ground available. Use a tester to see if your outlet is grounded. A series of lights indicates whether the outlet is wired correctly or what fault exists. These testers are readily available at home centers and hardware stores. If you discover a three-slot outlet in an ungrounded box, the easiest fix is to simply replace it with a two-slot outlet as shown.
Recessing Boxes Behind the Wall SurfaceMistake: Exposed combustible material | Electrical boxes must be flush to the wall surface if the wall surface is a combustible material. Boxes recessed behind combustible materials like wood present a fire hazard because the wood is left exposed to potential heat and sparks. Solution: Add a box extension | The fix is simply to install a metal or plastic box extension. If you use a metal box extension on a plastic box, connect the metal extension to the ground wire in the box using a grounding clip and a short piece of wire.
Installing Cable Without a ClampMistake: Missing clamp | Cable that's not secured can strain the connections. In metal boxes, the sharp edges can cut the insulation on the wires. Single plastic boxes do not require internal cable clamps, but the cable must be stapled within 8 in. of the box. Larger plastic boxes are required to have built-in cable clamps and the cable must be stapled within 12 in. of the box. Cables must be connected to metal boxes with an approved cable clamp. Solution: Install a clamp | Make sure the sheathing on the cable is trapped under the clamp, and that about 1/4 in. of sheathing is visible inside the box. Some metal boxes have built-in cable clamps. If the box you're using doesn't include clamps, buy clamps separately and install them when you add the cable to the box.
- 1 - for each hot wire and neutral wire entering the box
- 1 - for all the ground wires combined
- 1 - for all the cable clamps combined
- 2 - for each device (switch or outlet?but not light fixtures)