6/10/2010 4:25 PM | |
Joined: 9/27/2006 Last visit: 11/4/2024 Posts: 12293 Rating: (2690) |
Hello Viana; I would say: Less and less difference every day, now. At the time they were introduced (in the late '70s, and 1980s) DCS (Distributed Control Systems) were developped for continuous or batch process control of large processes: rafineries, steel mills, and such. They were using central processing uints (mini-computers at the time) based on Unix-like systems, withproprietary communication buses to dedicated controllers with semi-autonomous loops in the field. Visualisation of the process parameters was done through terminal screens. The first PLCs were developped at the same time, and were oriented towards fast digital controls, good for manufacturing processes. SCADA and HMI completed the plants where digita;l controllers were implemented, to allow operator interface and data acquisition. Both systems have evolved over the years, and nowadays PLCs are very efficient at loop control and analog processing, whereas DCS have introduced high-speed digital controls. Introduction of standardized commecial hardware and software in the computer world has brought both DCS and SCADA/PLC systems closer in such a way that the newer DCS systems (such as Siemens' PCS 7) are actually base don integrated SCADa and PLCs. I can suggest a very good introduction to both DCS and SCADA systems in Wikipedia: http://en.wikipedia.org/wiki/Distributed_control_system http://en.wikipedia.org/wiki/SCADA Hope this helps, Daniel Chartier |
This contribution was helpful to2 thankful Users |
6/10/2010 4:40 PM | |
Posts: 2661 Rating: (279)
|
Hi Viana, In addition have a look at the following thread: PLC vs DCS Regards |
This contribution was helpful to1 thankful Users |
6/21/2010 1:58 PM | |
Posts: 130 Rating: (18) |
Hi, AttachmentDCS_PLC control0701.pdf (284 Downloads) |
This contribution was helpful to2 thankful Users |
Follow us on