An RCCB (Residual Current Circuit Breaker), also known as an RCD (Residual Current Device), is crucial in an electrical installation for several reasons: 1. Prevents Electric Shocks:RCCBs detect and disconnect the power supply if they sense a leakage current caused by faults like touching a live wire. This protects people from severe electric shocks. 2. Protects Against Fire Hazards:Leakage currents, especially through faulty wiring or appliances, can cause overheating and lead to electrical fir