IEC 62310-1 Ed. 1.0 b:2005

applies to free standing a.c. static transfer systems (STS) intended to ensure the continuity of power to load by automatically or manually controlled transfer, with or without interruption, from two or several a.c. independent sources. includes requirements for the switching elements, their control and protective elements, where applicable. This part of IEC 62310 also includes information for the overall integration of the STS and its accessories into the a.c. power distribution system