Answer / naveediqbalsher@yahoo.com

PLC mean programmable logic controler
DCS mean distribution control system
before different plc have digital inputs & outputs but DCS
digital & analog both.
now new plc also both digital & analoge inputs & outputs
in plc we can not change in software during running but in
DCS we can.also plc for small inputs &outputs but dcs for
big industries i mean more inputs & outputs.
plc have quick reponse than DCS.

Answer / muhammad nisar

1.No of I/O,S
2.Nature of process application i-e critical or non-critial
3.HMI form one or more Control Rooms
4.HOT SWAP(removing I/O Cards during plant Running)need or
not.
5.Plant Future extension required or not.
6.Logical synchronous or Non synchronous system require
7.Progamming Fexibility level requirements
8.Single Control process required or Distributed
9.Permanent installation or for short time
10.Expensive solution or non-expensive
and many more factors can easily diffrentiate it.

MUHAMMAD NISAR (I/C PROJECT MANAGER)

Answer / ghanshyam khatri

i am agree with ans 2,in a simple language dcs means
multipule plc and multiple scada's combinition.

Answer / muralikrishna y

plc is used for the system one or two functions controling
at a time , at the time the dcs will contolling the no of
fuctions at a time . mallfunctions zero compare to plc.

Answer / mohamed rafik

PLC - PROGRAMMABLE LOGIC CONTROLLER

It is sequential Control the limited I/O'S from the digital & analog.and it's single device to control the field process variable.


DCS - DISTRIBUTED CONTROL SYSTEM

It is continuous control the no of I/O's from the field.and it is consist no of controller to control the no of process variable.

Answer / muralikrishna

plc, dcs are the controllers,
plc it controlling or operatig only one function
dcs it is controlling no functions at a time.
plc(one i/p---->one o/p)
dcs(one (or)more i/ps------> no of o/ps )

Answer / uprabhagaran

PLC IS WORKING FOR PROGRAMMABLE BASED,AND ONLY DIGITAL
OUTPUTS,NO SCREENING.
BUT,DCS IS USING FOR CONTROL THE LOGICS,AND MONITORING.

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