Electric power lines that go into your home consist of three wires with differently-coloured insulating sleeves in red, black and green. Red is the “live” wire that carries the electric current. The green wire is the “earth” wire, and black is the “neutral” wire. Both the earth wire and neutral wire act as safety measures. The earth wire diverts excess current, such as those from a lightning strike. Neutral wires return currents to the power source to regulate voltage.