What is the primary role of a distribution board in a building electrical system?

• A. To generate electrical power.
• B. To receive supply, provide protection, and distribute power to branch circuits.
• C. To store energy for later use.
• D. To measure energy consumption only.

Answer: (B)

The main job of a distribution board is to take the incoming electrical supply and split it safely to the building’s various circuits while providing protection. It sits in the system after the main service equipment and contains the devices that disconnect power if something goes wrong—circuit breakers (and sometimes fuses or RCDs) for each branch. When a fault or overload happens in a branch, the corresponding protective device trips, cutting the current and protecting wiring, devices, and people. This combination of receiving power, protecting circuits, and distributing to branches is what makes the distribution board essential. It doesn’t generate power, store energy, or serve only as a meter; metering can be a feature in some boards, but the core purpose is protection and distribution.