The ZN85-40.5 PT handcart indoor vacuum circuit breaker is an intelligent switchgear designed specifically for 40.5kV power systems, integrating voltage transformer (PT) function to achieve voltage monitoring and protection integration. Adopting vacuum arc extinguishing technology, the short-circuit current breaking capacity is as high as 40kA, and the modular design of the handcart supports quick insertion and removal, increasing maintenance efficiency by 50%. Compliant with GB/T 1984 and IEC 62271-100 standards