triplex cable (Three-core cable) is a common type of power transmission cable, widely used in residential, commercial and industrial power distribution systems. It consists of three independent conductors and is usually used for power distribution in three-phase alternating current. A distribution board, also known as a DB box, is like the central hub of an electrical system. It contains multiple circuit breakers and connects various electrical circuits to ensure the safe flow of electricity throughout the building. After stepping down the voltage through the transformer's low-voltage side (0. Unlike traditional 2-core wire with only live and neutral wires, 3-core wire add a third core is the earth wire to protect users from electric shock.