"This part of IEC 62909 specifies general aspects of bi-directional grid-connected power converters (GCPC)@ consisting of a grid-side inverter with two or more types of DC-port interfaces on the application side with system voltages not exceeding 1 000 V AC or 1 500 V DC. In special cases@ a GCPC will have only one DC-port interface@ which is connected to a bidirectional energy-storage device. This document includes terminology@ specifications@ performance@ safety@ system architecture@ and test-case definitions. The ""system architecture"" defines interaction between the inverter and converters. Requirements which are common@ general@ and independent of special characteristics of individual generators and bi-directional storages are defined. This document does not cover uninterruptible power supply (UPS) systems@ which fall under the scope of IEC 62040 (all parts). Requirements for internal and external digital communication might be necessary; the interface requirements including communication with distributed energy resources are provided in a future part of IEC 62909. All EMC requirements are defined by reference to existing IEC standards. External communication requirements are out of scope of this document. NOTE The control signal from the grid is not defined in this document."