l tight but would not be tight on the copper itself. Down the road, the connection could easily fail, leaving a room or two dark.

A new switch you want to put in is likely to be a little different from the old one. For one thing, switches didn’t used to have the green ground screws they do now. That screw is meant to receive one (bare) wir

You might be considering replacing switches and receptacles (outlets) around the house. It sounds like a harmless electrical project, as long as you work with the power off. But you may not be aware of some likely pitfalls.

In the living room or bedroom, is the top or bottom half of an outlet controlled by a switch? If you replace such a switched outlet without keeping good track of where the wires connected, and if you don’t know a certain secret, things won’t work quite the same there when you’re done. Your new half-switched receptacle needs to have its two halves isolated from each other, just as the old one had. This won’t happen by magic. You have to break off a metal tab located on the live (hot) side, and don’t break the one on the other (white) side.

Receptacles in general need some care in how wires are connected to them. I will give just one example. Suppose the old receptacle had the wires pushed into holes on the back. Maybe you heard that a more reliable connection method is to attach them to the screws on the side. Well, once you get the wires loose from the old outlet (with a very small screwdriver or some twisting), your new connections at the screws might be worse than before if you don’t strip a little more insulation off each wire. Otherwise, some of that insulation can easily get trapped under the screw also. This connection would feel tight but would not be tight on the copper itself. Down the road, the connection could easily fail, leaving a room or two dark.

A new switch you want to put in is likely to be a little different from the old one. For one thing, switches didn’t used to have the green ground screws they do now. That screw is meant to receive one (bare) wire

witched outlet without keeping good track of where the wires connected, and if you don’t know a certain secret, things won’t work quite the same there when you’re done. Your new half-switched receptacle needs to have its two halves isolated from each other, just as the old one had. This won’t happen by magic. You have to break off a metal tab located on the live (hot) side, and don’t break the one on the other (white) side.

Receptacles in general need some care in how wires are connected to them. I will give just one example. Suppose the old receptacle had the wires pushed into holes on the back. Maybe you heard that a more reliable connection method is to attach them to the screws on the side. Well, once you get the wires loose from the old outlet (with a very small screwdriver or some twisting), your new connections at the screws might be worse than before if you don’t strip a little more insulation off each wire. Otherwise, some of that insulation can easily get trapped under the screw also. This connection would feel tight but would not be tight on the copper itself. Down the road, the connection could easily fail, leaving a room or two dark.

A new switch you want to put in is likely to be a little different from the old one. For one thing, switches didn’t used to have the green ground screws they do now. That screw is meant to receive one (bare) wir

cated on the live (hot) side, and don’t break the one on the other (white) side.

Receptacles in general need some care in how wires are connected to them. I will give just one example. Suppose the old receptacle had the wires pushed into holes on the back. Maybe you heard that a more reliable connection method is to attach them to the screws on the side. Well, once you get the wires loose from the old outlet (with a very small screwdriver or some twisting), your new connections at the screws might be worse than before if you don’t strip a little more insulation off each wire. Otherwise, some of that insulation can easily get trapped under the screw also. This connection would feel tight but would not be tight on the copper itself. Down the road, the connection could easily fail, leaving a room or two dark.

A new switch you want to put in is likely to be a little different from the old one. For one thing, switches didn’t used to have the green ground screws they do now. That screw is meant to receive one (bare) wir

ws on the side. Well, once you get the wires loose from the old outlet (with a very small screwdriver or some twisting), your new connections at the screws might be worse than before if you don’t strip a little more insulation off each wire. Otherwise, some of that insulation can easily get trapped under the screw also. This connection would feel tight but would not be tight on the copper itself. Down the road, the connection could easily fail, leaving a room or two dark.

A new switch you want to put in is likely to be a little different from the old one. For one thing, switches didn’t used to have the green ground screws they do now. That screw is meant to receive one (bare) wir

l tight but would not be tight on the copper itself. Down the road, the connection could easily fail, leaving a room or two dark.

A new switch you want to put in is likely to be a little different from the old one. For one thing, switches didn’t used to have the green ground screws they do now. That screw is meant to receive one (bare) wire extending to it from all the other bare (or green) ground wires in the switch box; you will probably have to supply this wire and connect it to the others with a wirenut.

If a switch you took out had more than two black wires attached to it, the two of those that were close together should be paired in a similar way on the new switch. Also, if a switch you want to replace controlled lights in conjunction with a switch at the other end of the room, hall, or stairs, it is a three-way switch (3 non-green screw terminals) or a four-way switch (4 non-green terminals). So you have to buy new switches with the same designation. And if you don’t keep track of where the different wires connected on the old 3-way switch and duplicate that on the new one, there is only a chance that you will get this set of switches to work the lights as they used to -- on your first try it is only an 11% chance!

Finally, if you are replacing old toggle-style switches with the “rocker” or “decorator” style, you may be in for some confusion in the case of 3-way switches. Some 3-ways of this new style have their terminals aligned in a way that does not correspond to the old toggle’s arrangement. A tip here is that whichever two wires were connected at the two same-color screws on the old switch should go to the same-color screws on the new one, with the wire that went to the one odd