What is SCADA ?  

What is SCADA ?
SCADA stands for Supervisory Control And Data Acquisition. It is a production automation and control system based on PCs.


It is widely used in many fields: e.g. power generation, water system, oil industry, chemistry, automobile industry. Different fields need different functions, but they all have below features:

  • Graphic interface
  • Process mimic
  • Real time and historic trending
  • Alarm system
  • Data acquisition and recording
  • Data analysis
  • Report generator



SCADA software accesses to hardware devices
Methods that SCADA software accesses to hardware devices can be easily classified to:

  • Standard communication protocol
    Common communication protocols used in industrial field are:
    ARCNET, CAN bus, DeviceNet, LonWorks, Modbus, PROFIBUS. If SCADA software and hardware devices use same communication protocol, they can talk to each other without any other extra software drivers.
  • Standard data exchange interface
    Common data exchange interface used in industrial field are:
    DDE (Dynamic Data Exchange)
    OPC (OLE for Process Control)
    Using standard data exchange interface, SCADA software can indirectly communicate with hardware devices via data exchange center of DDE and OPC. The advantage is: no matter hardware devices support standard communication protocols or not, manufacturers only need to provide one DDE or OPC driver to support most SCADA software.
  • Native driver
    A native driver means it is developed for specific hardware or goal. Advantages of using native drivers is: getting better execution performance than using standard data exchange interface. But its drawback is bad compatible ability. Manufacturers need to provide specific drivers for specific SCADA software.
    Using one of above methods, you can combine SCADA software and hardware devices. The communication structure is:


Famous SCADA software:
Citect, ICONICS, iFIX, InduSoft, Intouch, Entivity Studio, Entivity Live, Entivity VLC, Trace Mode, Wizcon, Wonderware ... etc


Resources from ICPDAS

  • Standard communication protocol
    Modbus/RTU and Modbus/TCP
    • ISaGRAF embedded controllers:
      I-8417, I-8817, I-8437, I-8837, I-7188XG, I-7188EG
    • Modbus/TCP embedded controllers
      I-8431 -MTCP , I-8831 -MTCP
      I-7188E -MTCP
  • Standard data exchange interface(Free)
    OPC Serve (NAPOPC DA Server)
    DDE Server (DCON_DDE)
  • Native driver (Free)
    ActiveX component (DCON_ActiveX)
    Bundled driver for Labview (DCON_Labview)
    Bundled driver for InduSoft (DCON_InduSoft
Copyright© ICP DAS Co., Ltd. All Rights Reserved