Answer / amzad pathan

These question is very difficult in todays Automation
system, Because Today's PLC is much more upgraded & working
like a DCS. Although PLC is Better for Sequincial
Operation, Because its Scan Time is less than DCS & DCS
mostly used for Continues Process.

If You see todays PLC, Its IO Capacity is near to DCS IO
handling Capasity. Yaa, one Big Advantage of DCS System is
that Logic of whole process is Split in Defferent different
CM's. So that when change in one CM do not affect other
Proccess.

Answer / wesam

Big difference between DCS and PLC.
PLC is a part of DCS it deals with I/O signals of a system,
however DCS is a high level of control.
A typical DCS contains
1-Monitors for view and control.
2-HMI at field which contains a PLC system.
and this HMI is connected by a modbus or a fiber optical
link, all critical signals are hard wired to DCS.
An OPC system for interfacing is used in case of multy DCS'
for different manufactures.
in addition we are able to control multy HMI systems in one
time through a DCS.

Answer / venkates

number of I/Os is high in DCS compare than PLC

Answer / chauhan

DCS is a master system while PLC is sub system. All Plc can
work independly but a Plc or number of Plcs can be control
by Distributed control system

Answer / indu

DCS is distributed control system,in which we can control many process in case of any sefe-failure operations,there wont be any problem in controlling it,But according to plc it cant control mutiple functions.In case of any problem,the entire process which it controls gets affected.i thnk like ths......it may be wrong

Answer / vijayaprakash

plc : programmable logical controller
DCS :Distribution control system

in PLC scanning time less compare to DCS

Digital operation plc performance to good compare to dcs

in analog operations plc are slow responding compare to dcs

DCS: its performance in analog operations good compared to DCS

Answer / instrument technician

dear sir can you helping me instrument qustion anser

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