This part of IEC 62040 establishes the performance and test requirements applied to movable, stationary and fixed electronic uninterruptible power systems (UPS) that " are supplied from AC voltage not exceeding 1 000 V; " deliver AC output voltage not exceeding 1 000 V; " incorporate an energy storage device not exceeding 1 500 V DC; and " have a primary function to ensure continuity of load power. This document specifies performance and test requirements of a complete UPS and, where applicable, of individual UPS functional units. Requirements for the individual UPS functional units found in IEC publications listed in the bibliography apply so far that they are not in contradiction with this document. UPS are developed for a wide range of power, from less than hundred watts to several megawatts, to meet requirements for availability and quality of power to a variety of loads. Refer to Annexes A and B for information on typical UPS configurations and topologies. This document also includes UPS performance and test requirements related to UPS switches that interact with other functional units of the UPS to maintain continuity of load power. This standard does not cover conventional AC and DC distribution boards and their associated switches; stand-alone static transfer systems covered by IEC 62310-3; rotary UPS covered by IEC 88528-11; and; DC UPS covered by IEC 62040-5-3.