One item that should be high on your list of home upgrades is the electrical wiring of all ungrounded outlets. Ungrounded outlets are two-pronged outlets left over from post World War II home construction. Modern homes are now electrically wired for a three-pronged world. Three-prong adapters are a handy work-around, but they are unsightly and prone to sag under the weight of the power cord.
It's much easier to just replace every ungrounded old two-prong outlet with a new three-prong outlet. But first, two brief reminders about electrical safety.
1. Always treat electricity with respect. A 110-volt jolt can be nasty and even fatal under wet or damp conditions.
2. Always be sure to turn off the electricity at the circuit breaker or fuse box and then double check the outlet for the presence of stray voltage.
Replacing ungrounded outlets
Upgrading a two-pronged outlet isn't a difficult task and can be accomplished by anyone with a basic understanding of household wiring. Naturally, you will need a few tools to complete the job. A respectable electrician's tool box will include a straight slot screw driver, needle-nosed pliers, a wire stripper, and an electrical circuit tester.
Electrical circuit testers are very important to have on hand as they are used to test for the presence of electricity. A typical circuit tester is a two-prong plug in device that lights up when a probe is inserted into an outlet or connected to a wire. Some electricians use multi-meters or electronic induction testers to perform this task. An electronic induction tester doesn't require inserting a probe into the outlet, as it sounds a distinctive chirping sound whenever the plastic tip is positioned near anything that is "hot", or carrying household voltage.
If these devices are not available to you, you can plug in a lamp or a radio to perform the same test, although they will not provide an indication if any stray voltage is present at the outlet. This sometimes happens if the two-prong outlet is incorrectly wired or there is a wiring problem elsewhere in the home. Troubleshooting the reason for the presence of stray voltages can be a difficult task and should be left to a professional if at all possible.
Steps for upgrading an ungrounded outlet.
Once you are satisfied that the electricity is properly turned off, the ungrounded outlet is safe to remove and replace. Here's how to proceed:
Step 1. Remove the ungrounded outlet's cover plate.
Step 2. Remove the outlet by backing out the top and bottom screws that hold the outlet in place.
Step 3. Note the position of the black and white wires. The black wire should be held in place with a brass colored screw. The white wire should be held in place with a lighter, colored screw. This is the "Black to Brass" and "White to White" wiring rule for connecting electrical wires correctly.
Step 4. Behind the outlet you will find a bare copper wire twisted around the outside, or sheath of the wiring cable. It is likely to be held in place with a larger screw and clamp attached to the inside of the outlet box. You have now identified all three wires. The black wire is the "hot" wire, the white wire is the return, or cold wire, and the bare copper wire is the "ground".
Step 5. Loosen the screws holding the wires to the socket. Remove the wires. the ungrounded outlet should now be detached. Discard it.
Step 6. Loosen the screw that holds the wiring cable and the copper ground wire in place. Pull out the cable and unwind the copper wire. Once the copper wire is free, tighten the holding screw and clamp again, securing the wiring cable firmly in place.
Note: If you are installing a plastic outlet extender, now would be the time to insert it. Outlet extenders are useful if the outlet's wall is covered with paneling, brick or Masonite.
Step 7. Attach the new three-prong outlet. First, trim the copper wire to approximately the same length as the black and white wire. Attach it to the grounding lug at the bottom of the outlet. This is usually a black hex-head screw that is located on the outlet's metal mounting bracket.
Step 8. Connect the black and white wires to the brass and "white" attaching screws. You may find this easier when using a pair of needle nosed pliers to hole and work with the wires. If the wires have a loop formed at their ends, needle nosed pliers will help you opening and closing the loop so you can make a good connection. Be sure to make a "nice and neat "connection without any wire left sticking out in any direction. Tighten the holding screws firmly, checking the wires for security as you go.
Note: If you are installing a three-pronged outlet using the pressure-clips that hold the wires in place instead of using the screws, be sure that your wires are straight and cut to the proper length. Most three-prong outlets have a wire-length guide molded into the body of the outlet. Be sure to follow the manufacturer's instructions.
Step 9. Push the three-prong outlet and the wires back into the outlet box. Then secure the outlet using the mounting screws that came with it. Install the cover plate.
Everything up to this point is going according to plan. The old two-prong outlet has been removed and a new, three-prong outlet is securely in place. It's time to turn the power back on and test the circuit using your circuit tester, or by plugging in any two- or three-prong device. If everything works and the circuit breaker doesn't trip or the fuse blow: congratulations are in order. Well Done!
Before signing off, however, there is one more check usually made by the informed home repair person. There is a small three-prong circuit tester that checks for proper wiring. This device is inexpensive and a great confidence booster when it comes to verifying that your household wiring is connected properly. This is a useful device that should be added to your home electrician's tool box.