From the bus bar, power is fed to multiple Miniature Circuit Breakers (MCBs) or fuses, each protecting a specific lighting circuit. If an overload or short circuit occurs, the MCB automatically trips, cutting power to prevent damage or fire. It is commonly used in homes, offices, and industrial settings to control and protect electrical circuits. Understanding its significance. Surge Protection Devices (SPDs): These step in during voltage spikes, like lightning strikes or grid surges, and help shield your appliances from sudden damage.