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Q In the Sept. ’04 issue, you stated that the neutral wire must be connected to the silver screw. Why does it matter which side of the light bulb is connected to the neutral? It’ll work either way.
—Ray M., via e-mail
A It’s a safety issue.Normally, power (voltage) comes through the tab on the socket base. The threaded socket is the neutral. So when the switch is off, all “hot” parts of the lamp are well protected. And when the switch is on, only the tab at the bottom of the socket is “hot.”But if the wiring is reversed and the power goes to the threaded socket, the threaded socket is always hot, whether the switch is on or off. There’s a much greater potential for getting a dangerous shock, especially when changing a bulb. The worst situation occasionally occurs in old fixtures when the cardboard insulation sleeve wears out and the outer metal shell of the socket touches the threaded socket. If the threaded socket is hot, every metallic part of the lamp becomes hot! Remember when repairing lamps, the neutral wire in the lamp cord is marked (usually with a rib or ribs) and it connects to the wide blade of the plug at one end and to the neutral screw (usually silver but may have some other identification) at the other end.
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