Dcs Plc Scada

[Unregistered]

I would like to know the diff in working principles of PLC, SCADA and DCS. The selection criteria for each of them.

Advance Thanx

 

[rsdoran]

multiple threads I see. Your book(s) glued shut?

I know guys this isnt my standard method of answering but geez these questions are so...........

SCADA is Supervisory Control and Data Acquisition, the name says it all. Its a program (usually run from a PC) that allows control and data acqusition.

PLC is just what the name implies...programmable controller. It was originally designed to replace relays, timers etc but as time has passed it has obtained capabilities far beyond the original concept.

DCS is Distributed Control System...in the other thread someone mentioned Logix5000 cards being used in a DCS system, well AB/Rockwell/Reliance has been doing that for many years. A DCS is a control method that distributes among many different processes.

There is a fine line today between all of the above.

 

[Ron Beaufort]

try this old post ...