Ceiling Light Switch Wiring

Hot Wire

• The hot wire is the black wire that carries current from the circuit or fuse panel to the ceiling light switch box. At the switch box, it connects to one of the screw terminals on the light switch. The black wire from the switch to the ceiling light connects to the other terminal. When the switch is in the on position, the path from the panel to the light is complete, energizing the fixture. When the switch is off, the path is broken and the current stops at the switch, making the fixture safe.

Neutral Wire

• The white wire running from the panel to the switch box is the neutral, or return, wire. The neutral provides a path for the current to travel from the fixture back to the panel. This completes the electrical circuit and allows the ceiling light to work. The neutral wires connect together in the switch box using a wire nut or similar terminating device.

Ground Wire

• In the event of a short-circuit or malfunction, the ground wire provides a safe path for the current to follow to the grounding rod or electrode outside the home. Without a properly installed grounding circuit, transient current will follow any path to ground it can find. If you happen to touch an ungrounded switch that has malfunctioned, you may become the path to ground, resulting in a shock or electrocution. The ground wires in the switch box twist together, with one wire left longer than the others, creating a “pigtail.” The longer wire connects to the green grounding screw on the light switch.

Multiple Switches

• For ceiling lights controlled by multiple switches, it is necessary to trace and identify the individual wires, as some white wires may be acting as hot wires. It is a good practice to mark white wires with black tape or paint when they serve as hot wires, but not every installer follows this practice. It may be necessary to enlist the services of a qualified electrician who has the tools and expertise to identify the correct wires and make the connections safely.