Connects to end-use equipment via switch boxes, forming a three-tier power distribution system. Residual current devices (RCDs) at both the tertiary (equipment-level) and secondary (zone-level) stages. Ensures safe disconnection in case of faults or leakage currents. After stepping down the voltage through the transformer's low-voltage side (0. 4kV), power is distributed to a main distribution panel (primary distribution box). From there, it is routed to individual building distribution boxes (secondary distribution boxes), which subsequently supply power to unit-level distribution boxes. The three-level distribution system refers to a system that distributes electric power through three levels of distribution devices from the incoming power line at the construction site to the electrical equipment. Today, electrical systems are essential for homes and industries. But what exactly is a power distribution box, and why is it so essential in our daily lives? The DB panel board controls the flow of electricity. A distribution box is a low-voltage electrical enclosure that receives incoming power and distributes it safely to multiple outgoing circuits through protective and switching devices such as MCBs, RCDs, RCBOs, fuses, isolators, busbars, neutral bars, earth bars, and surge protective devices.