Answer Posted / www.islamqa.com
# PLC is first invented and developed to be used with
discrete - on/off control & with small scale applications.
# DCS is designed and fabricated to handle modulating/PID
control applications & to serve in large scale I/Os
applications.
# with great progress and achievements in plc h/w and
networking technologies we have PID algorithms with PLC and
also plc become able to handle wide range of I/O'S like
DCS, actually with good engineering the one can build his
own DCS with multible PLCs.
# But actually with great engineering to build the DCS from
multible PLCs it will not be the same as pre-built/ready to
use DCS system in its functionality and its features.
# DCS is pre-fabricated system with compatible, integrated,
and tested H/W & S/W - has the following features:
- data collection & management.
- event and history management.
- instrument management.
- alarms management.
- smart and self diagnostics.
- advanced control strategy and easy to build, configure
control loops.
- redundancy.
Regards,
Ahmed Sabry
Control and Instrumentation Engineer
GPC - General Petroleum Company
ahmedsabry.online@gmail.com
CELL.: 00 2 0121367310
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send me model hpcl questions pleas..........my mail id mohideen.dharvesh@gmail.com
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