Old receptacles can pose a problem. Loose connections and the lack of grounding are among the problems that appear. Let’s discuss the disadvantages of two-slot receptacles in the home.
Receptacles, often referred to as outlets, come in many different styles. Two-slot receptacles have only two slots, a hot and a neutral. The smaller slot is connected to brass-colored terminal and is the hot wire connection. The longer slot is connected to the silver-colored terminal and is the neutral connection. This means they have no ground slot, making them much more unsafe than the newer, updated versions that include a ground slot. You see, if correctly wired, meaning the hot wire is connected to the smaller tab connection terminal and the neutral wire is connected to the larger tab connection terminal, most codes will allow their continued use. If you are adding new, additional outlets to the circuit, those should be the grounding type and it would be a great time to update the existing outlets as well.
So what do I do if the wiring is only a two-wire system that doesn’t implement a ground wire? Well, you have three choices as I see it. First, leave it in place if the wiring and devices are in good working order. By that I mean that there are no loose connections when you plug cords into outlets, switches are not making arcing sounds or flashing the lights when turned on and off, and there are no visible signs of burns around devices. Second, to make the existing wiring function more safely, simply replace the polarized outlets with ground fault circuit interrupters (GFCI) receptacles. This cost-effective method makes the outlet safer because when the GFCI detects a ground fault, it will trip and kill power to the circuit outlet. Depending on the way you wire it, you can protect only that outlet or it and the downstream outlets. This still doesn’t provide a ground wire, but it does add a level of protection for the homeowner without rewiring the home. Third, you can rewire your home with a grounded cable, usually a 12-2 cable with a bare ground wire. The outer cover of the cable will list this, denoting it as 12-2 w/grd. Rewiring is the best choice if your budget allows. Not only should the wiring be changed, but the receptacles as well. You see, the polarized outlets have no ground screw or ground slot, so there is nowhere to connect the ground wire. That’s why new, three-slot receptacles should be used to replace the polarized outlets.
One more thing that you may not have thought about is the older outlets that have the same sized slots. Oh boy, dangerous, and let me tell you why. Consider a light socket with the outer side wall that allows you to screw in a light bulb. This is the neutral connection for the light. The inner post of the socket is for the hot connection. If these are reversed, you could see the danger that is present. The outer socket would be hot and the inner would be the neutral. Although the light would work, there is a danger now present for anyone unscrewing or screwing in a light bulb. The slightest touch of the outer metal portion of the bulb and you could receive a shock. Likewise, incorrect wiring on the receptacle connections can allow this to happen. Be electrically safe in your home and consider upgrading from two-slot receptacles.