Answer / rohan garibe

PLC is a programmable logic controller, which is a
centralised system. It only helps in implementing a
pre-defined and stored logic program in its memory.
DCS is Distributed Control System. As its name implies, it
is a system whose control functions are distributed
geographically and functionally over a large area. It has a
great coverage in industry.

Answer / akg d gr8

DCS has more storage space compared to PLC

Answer / yogesh

1.PLC USED FRO REPALCING RELAY LOGIC. FEW YEAR AGO, THE
MAJOR DIFFERENCE BETWEEN PLC AND DCS WAS SCANNING TIME. BUT
IN TODAY TECHNOLOGY PLC SCANNING TIME HAS REDUCED.

2. WHEN YOU USE PLC , YOU NEED SCADA SYSTEM. BUT FOR DCS
SYSTEM YOU NEED NOT TO BUY OTHER SCADA SOFTWARE.

Answer / ravinder singh

there is as it is not much difference between DCS and PLC.
PLC can be regarded as a part of a DCS. in dcs, the clock
frequency is very high, because of which its very easy to
control analog signals. it gives a good linearity to the
analog signals. it has large storage space, integrated
modules for all sorts of i/os. high processing speed.

Answer / kk

1.PLC -Programming Logic controller .to PLC have faster
scaniing time.like diffrent CPU have diffrent scanning time.
2.like CPU 414-have .1ms scanning time simense.CPU 412 .2ms.
for monitoring and controling SCADA but in scada we can't
change engineering value.only monitoring and controle can
use SCADA.
3.PLC is relay logic control system.when any one RACK CPU
card fauiler then hole system will be stop suddenly.
DCS-Distributed controlle system.
1.DCS hase more space to store data.
2.DCS scanning time faster as compare to PLC.
3.DCS control the system functionlly and geographicaly.
4.area jone can be devided according process distribution.
5.have authority level to change the engineering value in
engineering section.
6.During the fauilure time u can get the particulre
instrument Data.

Answer / ibrahim s

PLC(Programable Logic Controller):
It is used to emulates relay logic interlock and provide
device status.
It works by looking at its input and depending upon
their state turning on or off its outputs.
It control the devices according to user defined logical
program.

DCS(distributed control system):
Group of PLC connected in a single loop, additionaly it
cabable to handle more input and output.
A server and/or applications processor may be included
in the system for extra computational, data collection, and
reporting capability.

Answer / parmar.ic@gmail,com

1) PLC=Programmable Logic Controller DCS=Distributed
Control System
2) PLCs are stand alone and perform a particular task,
DSC is a network of PLCs/RTUs that communicate in some
fashion to accomplish a particular task.
3)PLC only handled sequential process than DCS can handled
both Continue process and large loop control.
4)PLC doesn't have dongle so peple can crack the software
easy.
DCS have a dongle so it's only license to industry which
have it.

Answer / charankumar

Nowadays we cannot differentiate Plc and Dcs ,we can use
for both variable control & digital control

Answer / rakesh kumar .n be

PLC will have faster date processing then dcs..... PLC will send the date 50ma while DCS will 500ma.... it is not the accurate valve it is the bacic difference.

according to the Architecture PLC is easy but DCS is difficult, but DCS is good because in DCS we use HPM->HPMM->FTA->FCS->Field (redundancy is good in DCS)

Answer / linilbabu.ck

DCS means distributed controlled system PLC means program
logic controller Plc is works, which helps of the given
software with the appropriate ladder logics operations.Plc
is contructed the one or more micro controlled ICs(input
and output,power supply)The micro controlled ICs power
ratiing 5volt/4ma ie Plc is the power rating 12volt,24volt,
48volt etc.micro controlled ICs power ratiing 5volt/4ma is
converted the corresponding plc 12volt,24volt, 48volt
etc.plc input is conneced the computer and the output is
logically operated ie on or off conditions.ie
relay,optocoupler,magnetic proximity switches
connecting.Plc of the lader logics loded through computer
with the given software.distributed controlled system DCS
is the hardware port of the plc

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