A dual power distribution box is a power guarantee equipment that seamlessly switches between common and backup power sources through an automatic switching device. Its core function is to ensure power supply continuity and reliability. The device is equipped with a main line access module and a backup line access module. It adopts a mechanical interlocking structure and an intelligent processor to coordinate the switching process, and the switching time can be controlled within 200 milliseconds. Typical application scenarios cover high-rise buildings, hospitals, financial institutions, and other places with strict requirements for power supply stability. At the same time, improved models with integrated voice alarms, anti-theft warnings, modular wiring, and other functions have been derived. Through the combined application of components such as circuit breakers and temperature sensors, security mechanisms such as overcurrent protection and heat dissipation monitoring are formed.