5. Operator Panel
connected in parallel
with a PLC
S1 S2 S3 S4
S1, S2 etc are switches
B1 B2 B3 B4 B5
B1, B2 etc are bulbs or indicators
6. Simple Example
Entrance
block PT1 PT2
Side
block
Stopping
device
Tile
feeding
Motor PR2 PR1Elevator Production
line
Auto
Man
T1 T2
IT2
T3
IT3
T4IPR1 IPR2
T5
IT5
T6
IS4
T7
IT7
IPT1 IPT2
Operator Panel
7. Limitations
1. You need additional input in the PLC for each operator switch
2. You need additional output in the PLC for each indicator
3. Operators has to remember the meaning of each indicator
4. All possible error messages will be limited to bulbs
5. It is difficult to arrange for the operator to insert numerical values
Advantageous
1. Simple to use and construct as well as maintain
2. Less cost
3. No additional programming requirement as in serially connected ones
4. No requirement to match the PLC with the operator panel
8. Types of Controllers
and Monitors
CPU and I/O modules in built
CPU and Operator panel in built
Types of Operator panels
Graphical User interface
Text display
only
+key board
Monitor +
Key board
Touch panels
11. Programming an
Operator Panel
User friendly software are available. The programmer
does not need to bother about data communication with
the PLC. It is taken care of by the software
Programmer needs to design the operator panel, text
display graphical displays, error messages etc.
12. Programming
Continued
Stamp1 Stamp2
No. of Stamp1= input field
No. of Stamp2= input field
Current no. of Stamp1= output field
Current no. of Stamp2= output field
MB1
MB2
MB3
MB4
13. In the PLC program C1
MB1
UP
R
PV
C2
MB2
UP
R
PV
LD C1
T MB3
LD C2
T MB4
14. Ability to use more
than one Display
Screen 1 Press a function Key
Or arrow key
Screen 2
15. Example
Sorting Table
Left conveyor
Right conveyor
ms2 ms3 ms4
ms5 ms6 ms7 ms8
Light ms9
Left conveyor sorting table
panel
ms10 ms11 ms12
ms13 ms14 ms15 ms16
Light ms17
Right conveyor sorting table
panel
ps1
Ps2
Ps4
Ps3
is13
is14
21. SCADA System
Acronym for supervisory control and data acquisition,
a computer system for gathering and analyzing real time data.
SCADA systems are used to monitor and control a plant or
equipment in industries such as telecommunications, water
and waste control, energy, oil and gas refining and transportation.
A SCADA system gathers information, such as where a leak on a
pipeline has occurred, transfers the information back to a central
site, alerting the home station that the leak has occurred, carrying
out necessary analysis and control, such as determining if the leak
is critical, and displaying the information in a logical and organized
fashion. SCADA systems can be relatively simple, such as one
that monitors environmental conditions of a small office building,
or incredibly complex, such as a system that monitors all the
activity in a nuclear power plant or the activity of a municipal
water system. SCADA systems were first used in the 1960s.
22. SCADA system
Supervisory Control and Data Acquisition System
1. Graphics
You can visualize the system from the control room
2. SCADA Server
Alarm detection and scaling function
3. Alarm/Events
Real time processing with alarm and events
4. Multiple Trends
23. SCADA system contd.
Supervisory Control and Data Acquisition System
5. Communication
Serial, parallel TPC, IP based network
6. Reporting
Alarm detection and scaling function
7. Interfaces
Support for various interfaces, open protocol
8. Time synchronization
24. More facilities
1. Calculation facilities
2. Historical record and trend facilities
3. Connect with external interfaces
4. Connectivity
Price of the software depends on
Software points
Facilities included
End user license or development type
25. SCADA Architectures
First Generation – Monolithic
Computing was done in mainframes and network did not exist
No connectivity to other systems
Second Generation – Distributed
The processing was distributed across multiple stations that
are connected via LAN and share the information real time.
Third Generation – Networked
The current generations that used open system architectures,
Open protocols, distributing connectivity across WAN
