Server
Custom enum types:
User-defined enum types that do not exist in the standard system.
GVL:
In the Global Variable List, at least one instance of the server session function block, the IED data model function block instance, and optionally one or more Sampled Values and GOOSE communication function block instances are instantiated and initialized.
In addition, the code version used during code generation and the version of the TwinCAT Telecontrol Configurator used are also stored there.
Datamodel:
The entire hierarchical structure of the IED data model as function blocks. Also includes the IED block that is instantiated in the Global Variable List.
GSE / GSE adapter:
This function block connects a network adapter of the TwinCAT control computer with the GOOSE control blocks in the data model and controls the execution of these control blocks.
To be able to use GOOSE communication, the real-time network adapter must be commissioned and linked. This is explained in RT Ethernet adapter configuration.
The GSE adapter is a network adapter for GOOSE and Sampled Values communication whose network status is constantly queried by the corresponding function block.
Server:
This block contains a state machine, the basic states of which are used in every Server example.
The Server session block is responsible for establishing connections and exchanging data with a single Client. If there are multiple simultaneous Client connections, multiple instances of this block are required and instantiated.
Main:
The TwinCAT PLC project contains a "MAIN" program as standard. This is called cyclically by a TwinCAT task and in turn calls the program "P_IEC61850MAIN".
The program "P_IEC61850MAIN" encapsulates the call of the Server session block and the optional GSE block. It also separates the IEC 61850 communication from the rest of the PLC machine program.
Sampled Values
The control blocks in a Sampled Values configuration each require structures, function blocks, tasks, and programs.
Each program is assigned to a single task and calls all publisher function blocks at the same cycle time.
The Publisher function block establishes a connection between the network adapter of the TwinCAT control computer and the corresponding Sampled Values control block in the data model and controls its execution.
To be able to use GOOSE communication, the real-time network adapter must be commissioned and linked. This is explained in RT Ethernet adapter configuration.