Quick start
Simple projects with complete sources can be found here: IEC60870-5-104 central station.
Interoperability check list can be found here: Interoperability check list
Communication- and/or device error code overview can be found here: Error codes
Detailed introduction to implementation of controlled station in TwinCAT PLC can be found here: TUTORIAL
Short guide
Application object database
The application object database of the central station must be configured as hash table with the function F_iecCreateTableHnd. The individual array elements are linked with each other in the form of a hash table. This enables faster access to the individual data points, but also has certain disadvantages that must be taken into account:
- The size of the application database (array size) must not modify at runtime (e.g. through online change). The central station stops execution immediately and reports an error. The reason: The hash table links no longer match. When the program is modified it is best to load the complete project into the runtime system.
- The individual array elements must not be accessed via the index but via the special functions (e.g. F_iecAddTableEntry etc. ).
- With indexed table element access the internal configuration parameters must not be overwritten or modified. If the type, the ASDU address or the object address is changed the data point can no longer be found. To reconfigure a data point it should first be removed from the table via function call F_iecRemoveTableEntry. The new data point can then be added.
An implementation in the form of linear table would mean that for each received ASDU (data unit) the central station would have to search the complete array for a suitable element. With many data points this would lead to long execution times.
Protocol parameters
The TCP/IP transport layer characteristics are configured via the protocol parameters. Most protocol parameters are preconfigured with default values and do not have to be set explicitly. However, the PLC application has to configure the IP address (sRemoteHost) and the port address (nRemotePort) of the substation as a one-off operation.
System parameters
The system parameters are also preconfigured with default values. During commissioning it is useful to activate debugging output (dbgMode) in order to be able to locate any errors.
Parameters for cyclic data acquisition
The following parameters are preconfigured with default values:
- Initialisation sequence (consisting of a test command, time synchronisation, station query and counter query);
- Cyclic commands:
- Test command every 60 s;
- Time synchronization every 60 s;
- Group station query: generally, every 60 s;
- Group counter query: generally, every 60 s;