Remote Terminal Unit (RTU) is a remotely located real-time data collector/controller and communication system that collects/send data automatically from sensors, meters, loggers or to process equipment; and communicate directly to a distributed master control system or SCADA (supervisory control and data acquisition system) master. Remote data monitoring is required in many industries and applications such as oil & gas, power, waste water treatment, and environmental monitoring. In these applications, a fairly large number of RTUs in remote and/or hazardous locations collect data from devices and send log data and alarms to a SCADA terminal in a central control room (CCR).

SCADA Remote Terminal Unit Hardware

Remote Terminal Units (RTUs) collect data automatically and connect directly to sensors, meters, loggers or process equipment. They serve as slave units to supervisory controllers or supervisory control and data acquisition (SCADA) masters. Remote Terminal Unit monitors the field digital and analog parameters and transmits all the data to the Central Monitoring System (CMS). Remote terminal units are located near the monitored process and transfer data to the controller unit on command. They often include integral software, data logging capabilities, a real-time clock (RTC) or totalizer, and a battery backup.

SCADA Remote Terminal Unit Communications System

Remote Terminal Units have interface with the central station with different communication media. Telemetry devices installed between the RTUs and the SCADA system send and receive the data. Communications between remote terminal units (RTUs) and supervisory controller and data acquisition (SCADA) systems takes place by conventional telephone lines, GSM/CDMA Mobile Communications, GPRS mobile data service, and/or Zigbee technologies.

SCADA Remote Terminal Unit Applications

  • Oil and Gas remote instrumentation monitoring, (offshore platforms, onshore oilwells).
  • Networks of remote pump stations (wastewater collection, or for water supply).
  • Hydro-graphic monitoring and control, (water supply, reservoirs, sewerage systems).
  • Environmental monitoring systems (pollution, air quality, emissions monitoring).
  • Minesite monitoring applications.
  • Protection supervision and data logging of Power transmission network
  • Air traffic equipment such as navigation aids (DVOR, DME, ILS and GP)