Remote terminal units (RTUs)

RTUs with hardware controller

In combination with a type-specific SIPLUS RIC library, hardware controllers from the following product series can be used as remote stations in telecontrol applications with IEC 60870-5-101 (serial) or IEC 60870-5-104 (Ethernet TCP/IP) telecontrol protocols:

Comparable controllers from the SIPLUS extreme product spectrum can be used for especially demanding environmental conditions. Information about the controller from the SIPLUS extreme product spectrum can be found in ST 70 catalog and on the Internet at: http://www.siemens.com/siplus

Controller for use as a RTU – parameters and scaling

For detailed technical information and ordering data for the RTU types listed in the table, refer to the ST 70 and ST PCS 7 catalogs.

RTUs with software controller

In combination with a SIPLUS RIC library, SIMATIC PC-based systems with a software controller (SIMATIC WinAC RTX, SIMATIC S7‑1500 Software Controller or SIMATIC ET 200SP Open Controller) are also suitable as remote stations in telecontrol applications with remote control protocol IEC 60870‑5‑101 (serial) or IEC‑60870‑5‑104 (Ethernet TCP/IP).

SIPLUS RIC Libraries

The SIPLUS RIC libraries for IEC 60870‑5‑101 and ‑104 protocols are delivered as master and slave. The library for the IEC 60870‑5‑103 protocol is only available as a master.

The product package for all SIPLUS RIC libraries include a CD with software and documentation and a certificate of license for all protocols and interfaces. With SIPLUS RIC libraries for SIMATIC ET 200S, SIMATIC ET 200SP, SIMATIC S7‑300 and SIMATIC S7‑1500 RTU types, a memory card (MMC/SMC) is also included. The product variations offered for a hardware controller type are distinguished by the storage capacity of the memory card.

A license is required for each of the two CPUs when redundant SIMATIC S7-400 systems are used.

Depending on the RTU type, activation can be performed using either the supplied memory card (ET 200S, ET 200SP, S7-300, S7-1500) or via the e-mail address siplus-ric.automation@siemens.com (S7‑400). All libraries of the respective series are activated.

Communication/network components

Communication/network components from the IK PI Catalog supplement the product range for configuration of IEC 60870‑5‑101/‑104 telecontrol applications using SIPLUS RIC libraries such as:

• TCP/IP converter and serial modem module
• Mobile radio components
• Industrial Ethernet switches, TCP/IP routers, and media converters
• SCALANCE W industrial wireless LAN components
• SCALANCE S industrial security modules, e.g. S612
• Dedicated line accessories
• Connecting cables

Network topologies

For the configuration of complete, hierarchical telecontrol networks, it is possible to implement basic topology forms such as point-to-point, multipoint, star and ring in various media forms and to combine them depending on the infrastructure requirements.

Examples of media forms

• Private networks
  • Radio
  • Dedicated line via fiber-optic cable or via modem
  • Ethernet network, e.g. with SCALANCE X and fiber-optic cables
  • WLAN, e.g. with SCALANCE W
• Public networks
  • GPRS
  • EGPRS
  • UMTS
  • LTE
  • DSL
  • Satellite communication, e.g. Inmarsat

Redundancy

Telecontrol communication availability can be improved by connecting the RTU to the control center in the process control system via two transmission paths. The two redundant transmission paths can be based on the same or different telecontrol protocols.

The use of redundant RTUs of type S7-400H (high availability) or S7-400FH (safety-related and high availability) results in further options for increasing the availability, e.g. redundant design of telecontrol communication, fieldbus and process I/O. As a result of the seamless integration of the telecontrol system in the SIMATIC PCS 7 process control system, its implementation depends on the redundancy concept of the complete system (see example of redundant telecontrol configuration with the IEC 60870‑5‑101/104 telecontrol protocols).

Example of redundant telecontrol configuration with the IEC 60870‑5‑101/‑104 telecontrol protocols

Connection of SIPROTEC protection devices

SIPLUS RIC IEC 60870‑5‑103 Master can also be used to connect protection devices such as SIPROTEC via SIMATIC PCS 7 TeleControl. The RTU then serves as a converter between the IEC 60870‑5‑103 protection data protocol and the IEC 60870‑5‑101 or IEC 60870‑5‑104 protocol.

Compared to PROFIBUS DP interfacing of the protective equipment, this configuration provides the following advantages:

• Longer distances achievable
• High precision time stamps are transferred from the protective equipment to the control system