WHAT IS THE DIFFERENCE BETWEEN PLC AND DCS
Answer Posted / mohammed ibrahim khaleel
1. In PLC the heart of the system is a controller,
which contains all logics.
In DCS the heart of the system is HMI.
2. In PLC Operators primary role is to handle
exceptions where as in DCS Operators interaction is
required to keep the process in target.
3. In PLC Status information on/off, Run/Stop is
critical information for operator. In DCS analog trends are
critical, alarm management is Key to safe operation &
failure of HMI could force a shut down.
4. in PLC logic scan is very fast approx. 10 ms is
required to perform function i.e.to change status of motor
where as in DCS scan time is large i.e. 100~500 ms.
5. In PLC redundancy may not be cost justified where
as in DCS system redundancy is often required.
6. In PLC you can’t change configuration online. it
requires offline means shut down where as in DCS online
parameters can be changed i.e. no shut down is required.
7. In PLC analog control is simple PID control where
as in DCS simple to advanced PID control up to advanced
process control.
8. In PLC's use Ladder logic to configure application
where as in DCS use function blocks to configure
application.
9. PLC is useful for small plant application where as
in DCS is used for large plants or number of small plants
to a single platform.
| Is This Answer Correct ? | 0 Yes | 3 No |
Post New Answer View All Answers
Explain the working of an electronic level troll.
What is the difference between ff transmitter and non ff transmitter
Make Heater Process Logic.
Why do we floating DC in DC system.
What is the GK Value in Flowmeter?
Somebody can explain me about >Critical Loops, calibrations, ESD critical Loop checks, Logic Diagram / Cause & Effect checks for ESD loops,
why Fahrenheit unit of moistur analyzer transmitter
1. For Steam drum level signal, why do we compensate with drum pressure signal? 2.For main steam Flow signal is comensated with main steam temperature signal and main steam pressure signal why?
Hi,can anyone help me out with PhD programs related to Instrumentation field?I have a degree in electronic Instrumentation?
How is PH sensor works ?
What is frequency factor in massflow meter? When using frequency output?
How to calibrate radar type level transmitter for interface level? Total liquid(liq.1 and liq.2), level both the liq individually? For. Both the liquid levels how the signal will go from transmitter to dcs? How to calibrate. Single radar 9:26:55 AM for 2 different liquids in a tank?
where proximity sensor installed on tank in loading arm application
why is an oxygen sensor used in a boiler stack
what are the different types of Protocols? & their applications.