EN 62310-2 applies to free-standing A.C. static transfer systems (STS) designed to ensure load supply continuity by controlling transfers between two or more independent A.C. sources, with or without power interruption. It includes requirements for switching elements, control, and protective components where applicable. The standard also provides guidance for the integration of STS and its accessories into the A.C. power network, covering systems up to 1,000 V A.C. for single-phase, phase-phase, or three-phase applications.