Before any data or command exchange can begin, the communication link between the controlling station (master) and controlled stations (RTUs or substation gateways) must be properly established. This process — called link initialization — ensures both sides start from a synchronized state with correct frame sequencing, clear buffers, and ready communication paths. Link initialization is part of the… Read More »
The IEC 60870-5-101 protocol (commonly known as IEC 101) is a serial telecontrol standard widely used in SCADA, power automation, and industrial control systems. It defines how data is formatted and transmitted between a controlling station (master) and controlled stations, such as RTUs or dedicated substation operation and data-handling devices. Each message on the line is called a… Read More »
The Originator Address in IEC 60870-5-101 is an optional but powerful feature that enhances message routing and command traceability in telecontrol and SCADA systems. This one-byte field, located within the Cause of Transmission (COT) section of the ASDU, allows a controlling station to explicitly identify itself when sending commands. In systems with a single master station, this feature… Read More »
In the realm of Supervisory Control and Data Acquisition (SCADA) systems, the IEC 60870-5 protocol suite is a fundamental standard for telecontrol and remote communication in power systems and industrial automation. One of the core technical distinctions within the IEC 60870-5-101 profile is between balanced and unbalanced transmission modes. These modes define how communication is initiated and managed… Read More »