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WHAT IS RTU?

RTU (abbreviation of Remote Terminal Unit in English) is an electronic device that contains a microprocessor control system, provides communication between physical field equipment and SCADA system, transmits signals and information from the field to the central control system and carries the commands from the central control system to the field.

RTU is used in SCADA and Automation projects in many fields such as energy, transportation, defense, petro-chemistry, food. RTU is especially used in managing points far from the center. Although the differences between PLC and RTU are decreasing day by day, RTU is preferred in projects where different stations need to be managed from a single center, especially due to the communication capabilities of RTUs. For example, RTU is successfully used in the management of water resources of a water management company with many wells and tanks. Again, RTUJ can successfully meet the full control needs of an oil production company with many production and storage points. RTU is preferred in projects such as cement factories where there are many different and many physical equipment and working conditions are very difficult and redundancy is indispensable.

BASIC RTU TERMS

  • Digital Input:

Digital Signaling / Dry Contact is the transmission of some status information of the equipment to the RTU processor according to the open or closed switch positions. These signals are used to operate information such as the position of a valve or the fault status of a device.

  • Analog Input:

Analog Signal is used to transmit device information as voltage or current to the RTU processor. Analog signals are information from transmitters, meters and sensors and are transmitted to the system by calibrating the values in a certain range in terms of voltage or current.

  • Digital Output:

Digital output is used to transmit information such as on / off sent to field equipment.

  • Analog Output:

Analog output is proportional information sent to field equipment and is in voltage or current. It is used in the control of equipment such as proportional valves.

RTU can communicate with smart devices through many different physical communication channels and supports many communication protocols. RTU models known in the market can communicate via RS232, RS485, RS422 or Ethernet using different protocols such as Modbus, Profibus, IEC 60870-5-101/103/104, DNP3, IEC 60870-6-ICCP, IEC 61850.

Thanks to these superior features, RTU plays a very important role in managing devices under many difficult physical conditions and in hard-to-reach places and making our lives easier.