what is the difference between PLC & DCS

Answer Posted / umashankar soni

PLC - is programmable logic controller
DCS - Distributed control system

The main difference between the two is there size i.e. in
market PLC is available in wide range of size from few IO's
to as large as you require,DCS is not.

PLC was earlier used to control sequential operation
only,whereas the DCS was for loop control.

Scanning time of PLC is very fast then that of DCS so where
the fast control is required the PLC is preffered as in
grid control system.

DCS comes with its graphis system where as in PLC
additional MMI softwere is require.

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