A light switch is the simplest of electrical devices. Flip the switch, electricity flows. Flip it again, electricity stops. Lights on, lights off. That's great for a small room with one entrance.

In the diagram ... end switch, and another three conductor cable to the fan. On the near end 3way switch, the panels black conductor connected to the input common. On the far end 3 way switch ...

There are two types of light switches, says Donnelly: a single-pole light switch, which has two wires, and a three-way light switch ... come into contact with the wiring, which is a high fire ...