Draft61850-7-3©1EC:2002 -7-57WG10-12(61850-7-3)R7.10/DraftFDIS INTRODUCTION This document is part of a set of specifications,which details layered substation communication architecture.This architecture has been chosen to provide abstract definitions of classes and services such that the specifications are independent of specific protocol stacks and objects.The mapping of these abstract classes and services to communication stacks is outside the scope of part 7-x and may be found in part 8-x(station bus)and part 9-x (process bus). IEC 61850-7-1 gives an overview of this communication architecture.This part of IEC 61850 defines common attribute types and common data classes related to substation applications These common data classes are used in part IEC 61850-7-4.To define compatible DATA classes the attributes of the instances of DATA shall be accessed using services defined in 1EC61850-7-2. This part is used to specify the abstract common data class definitions.These abstract definitions shall be mapped into concrete object definitions that are to be used for a particular protocol (e.g.MMS,ISO 9506).Draft 61850-7-3  IEC:2002 – 7 – 57/WG10-12(61850-7-3)R7.10/DraftFDIS INTRODUCTION This document is part of a set of specifications, which details layered substation communication architecture. This architecture has been chosen to provide abstract definitions of classes and services such that the specifications are independent of specific protocol stacks and objects. The mapping of these abstract classes and services to communication stacks is outside the scope of part 7-x and may be found in part 8-x (station bus) and part 9-x (process bus). IEC 61850-7-1 gives an overview of this communication architecture. This part of IEC 61850 defines common attribute types and common data classes related to substation applications. These common data classes are used in part IEC 61850-7-4. To define compatible DATA classes the attributes of the instances of DATA shall be accessed using services defined in IEC 61850-7-2. This part is used to specify the abstract common data class definitions. These abstract definitions shall be mapped into concrete object definitions that are to be used for a particular protocol (e.g. MMS, ISO 9506)