IEC TS 62271-313:2025 is applicable to direct current circuit-breakers (hereafter termed DC circuit-breakers) for indoor or outdoor installation having direct voltages of 100 kV and above for operation on DC transmission and distribution systems. This document includes the (mechanical) switching devices, including the residual current interruption devices, and their operating devices, power electronic switches, primary auxiliary circuits and energy dissipation systems, as well as their controls. Depending on design and system needs, operation can be for one current direction only (unidirectional) or for both directions (bidirectional).