ES7-Miniature Circuit Breaker (MCB) is a basic protective device used in low voltage electrical systems to protect circuits against overload and short-circuit faults. It is widely applied in residential, commercial, and light industrial electrical installations.The MCB is suitable for AC power systems with rated voltage of 230/400V,frequency of 50/60Hz, and rated current up to 125A. It is available in multiple pole configurations, including 1P, 2P, 3P, and 4P, and offers different tripping characteristics such as B, C, and D curves to meet various application requirements.Under overload or short-circuit conditions, the MCB can automatically disconnect the circuit, preventing damage to electrical equipment and reducing the risk of electrical faults. Its compact structure allows convenient installation in distribution boards, consumer units, and terminal distribution systems. The Miniature Circuit Breaker is designed and manufactured in accordance with IEC 60898-1 and GB/T 10963.1 standards, providing stable performance and reliable protection for everyday low voltage electrical installations.