A busbar connection system is an electrical connection used to connect two or more electrical devices. It provides a way to connect circuit breakers, fuses and other equipment together in a safe and secure manner. Also known as a circuit breaker adapter, this system is available in a variety of sizes and configurations to suit your application needs. The 400A 3P&4P busbar connection system is used to connect circuit breakers to electrical equipment with 400 amp three-phase and four-phase power.