TcIEC870_5_104Slave: IEC 60870-5-104 Controlled Station (slave)

Substations (Slaves) according to IEC60870-5-104 can be realised in TwinCAT PLC with PLC functions and function blocks.

The PLC library has two software interfaces. The end application is imposed on one of these interfaces. The choice of interface depends on the requirements for the end application. The characteristics of both interfaces are described briefly below.

 

'High level' interface: IEC 60870-5-104 Controlled Station

This interface is a so-called ‘single-block solution’. All functions are encapsulated in one PLC block. The block implements the most important services and functions. This implementation is sufficient for over 90% of applications.

Pro: Very little PLC programming work is required in order to create an application; all services, such as general query, counter query, time synchronisation, command execution, spontaneous data transmission etc. are already implemented in the block and are executed automatically; the mapping of the IEC<->PLC process data and that of the data points is configured via function calls; the PLC programmer does not need to be very well acquainted with the protocol standard;

Contra: The PLC application has only a small influence on the execution of the protocol; no influence on the execution of the services – these are automatically implemented internally; time stamps are automatically generated by the block and cannot be changed (handed over by externals); only the direct command execution, for example, is possible; poorer performance if there are many data points.

 

This interface is recommended if you:

 

'Low level' interface: IEC 60870-5-104 Transport Interface

This interface starts lower down on the protocol stack and enables the sending and/or receipt of individual frames (ASDUs).

Pro: Very flexible; all properties in the ASDU frame can be changed (e.g. an own time stamp, Select/Execute or a special command execution etc.); high performance can be achieved because only the necessary services are implemented; high performance if there are many data points;

Contra: Larger amount of programming work; all services, such as general query, counter query, time synchronization, command execution, spontaneous data transmission etc. must be implemented by the PLC programmer himself (programmed out); the PLC programmer must be familiar with the protocol standard.

 

This interface is recommended if you:

 

Interoperability check list

for TwinCAT PLC Library: IEC 60870-5-104 controlled station (relating to the "high level" interface). Here you can open/save the protocol interoperability document (zipped PDF).

 

System requirements

Development environment:

Target system:

 

Product components

 

Installation on Windows NT (XP, XPe/WES, Vista, W7, WES7, ...)

The PLC libraries are copied into ..\TwinCAT\Plc\Lib folder. The TwinCAT TCP/IP Connection Server is entered in the TwinCAT Server list. The TCP/IP Connection Server is automatically started when TwinCAT is started and stopped when TwinCAT is stopped.

Installation on Windows CE

Product version for the runtime system under Windows CE is available as separate product. If you have CE version, please do the following steps:

TcIEC870_5_104Slave: IEC 60870-5-104 Controlled Station (slave) 1:

This document is not full product manual. Please install the full version of the Beckhoff Information System.

You will find it

Examples

Example projects are in the Beckhoff Information System documentation of TwinCAT PLC library.

Link to 'high level' example overview page: IEC 60870-5-104 Controlled Station;

Link to 'low level' example overview page: IEC 60870-5-104 Transport Interface;

 

Further Documentation