QY-1-13-DM-U2-02 is a single-pole miniature DC circuit breaker designed for low-voltage DC applications with hydraulic-magnetic tripping technology. The device features a 13 mm ultra-compact module width with dual mounting capability (DIN rail and mini rail), a medium time delay curve (U2) with instantaneous trip point between 7–12 times rated current, and an 80 Vdc unpolarized operating voltage. It delivers an ultimate short-circuit breaking capacity of 10 kA and supports current ratings from 0.1 A to 63 A, with 100% rating capability independent of ambient temperature (-40°C to +85°C). The breaker includes trip indication with mid-trip handle, can be switched on immediately after tripping, and is suitable for electrical isolation applications. It is VDE, EAC, and CCC approved, CE certified, and UL listed (UL 489A), making it ideal for DC power distribution systems in renewable energy, telecommunications, and industrial control applications.