This is of about operation of chemical plants , architecture of DCS , PLC and their applications.

1. PLANT OPERATION
sysTEms
Typical objectives of plant operation include:
1. protect peopleprotect people
2. protect environment2. protect environment
3. protect equipment3. protect equipment
4. maintain smooth operation4. maintain smooth operation
5. achieve product rates & quality5. achieve product rates & quality
6. Profit=optimizing first five6. Profit=optimizing first five
7. monitoring & diagnosis7. monitoring & diagnosis

2. Distributed control system(D.C.S):
D C S is a computerized control system used to control the
production line in the industry.
D C S was introduced in 1975 by HONEYWELL and
YOKOGAWA(CENTUM).
Other vendors :ABB,FOXBORO, EMERSON (ROSEMOUNT)
AND ETC..,.

3. DCS ARCHITECTURE:
System
Consoles
Host
Computer
Data
Storage Unit
PLC
Data Highway (Shared Communication
Facilities)
Process Transmitters and Actuators
Local
Console
Local
Control Unit
Local
Control Unit
Local
Console

4. FIELD BUS TECHNOLOGY:
Introduced 1988but underwent many
development
 Standard IEC61158 introduced in
1999
 Based upon smart devices installed
in the field.
 Uses data highway to replace wires
for signal transfer.
 Can mix sensors, transmitters, and
control valves from different vendor

5. PLC ARCHITECTURE:
A plc is a micro processor based
controller.
Programming
Interface
Power Supply
Input Devices
I/O Modules
Output Devices
Processor
PLC Cabinet
Data Highway
A plc uses programmable
Memory to store
information and carry out
functions to control
machines and process.

6. REDUNDENCY:
Digital control system
sensorssensors
SIS system
i/o i/o i/oi/o
 We desire independent protection layers, without common-cause
failures - Separate systems
DCS handles controls and
alarms functions
PLC handles SIS and Alarms
associated with SIS

7. INPUTS:
These are typically “switches”
and “sensors”. The switches and sensors are
connected to an input module that provides
the interface between the switches (or)
sensors to the PLC.
OUTPUTS:
The plc output are connected
directly or indirectly(eg: Through relay) to
actuator controls. Eg: “solenoid valves” and
warning lights.
There are three main types of output
modules:-
1. RELAY
2. TRANSISTOR

8. APPLICATIONS:
 * Pneumatic machines.
 * Hydraulic machines.
 * Robots.
 * Production process.
 * Packaging lines.
 * Traffic lights & signalling systems.
 * Refining processes.

9. Basic control system:
TC TT
Actuator System
Sensor System
Controller
F1
T1
F2
T2
T
F

10. ACTUATOR SYSTEMS:
ON/OFF:
 ON – OFF VALVES
 PUMPS (MOTORS)
VARIABLE POSITION:
Control Valves
Variable speed pump
•DC motor
•3-phase motor
•Turbine drive

11. CONTROL VALVE:

12. BUTTERFLY VALVE:

13. ACTUATOR:

14. VALVE WITH ACTUATOR &
POSITIONER:

15. THANKYOU
 BY: MANIROOP.B
 15345A0428
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