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Ladder Logic Diagram is a symbolic language used in PLC. This diagram consist of series of SYMBOLS interconnected by lines to indicate the FLOW of current through the VARIOUS devices. In ladder logic diagram the sides of the ladder forms the POWER sources and current FLOWS through the various –logic input devices that form the rungs of the ladder.

Ladder Logic Diagram is a symbolic language used in PLC. This diagram consist of series of symbols interconnected by lines to indicate the flow of current through the various devices. In ladder logic diagram the sides of the ladder forms the power sources and current flows through the various –logic input devices that form the rungs of the ladder.

1. Input interface modules accept SIGNALS from the MACHINE or PROCESS devices (120Vac) and convert them into signals (5Vdc) that can be used by the controller.
2. OUTPUT interface modules convert controller signals (5Vdc) in to external signals (120Vdc) used to control machine or process.

1. Input interface modules accept signals from the machine or process devices (120Vac) and convert them into signals (5Vdc) that can be used by the controller.
2. Output interface modules convert controller signals (5Vdc) in to external signals (120Vdc) used to control machine or process.

1. They have to be hard-wired to perform a specific function
2. No hard-wire REQUIREMENT
3. When the SYSTEM requirement change, the RELAY wiring has to be changed or modified
4. Can be easily changed or EXPANDED through program
5. Higher power consumption
6. Lower power consumption

1. They have to be hard-wired to perform a specific function
2. No hard-wire requirement
3. When the system requirement change, the relay wiring has to be changed or modified
4. Can be easily changed or expanded through program
5. Higher power consumption
6. Lower power consumption

1. Sequence control, timing, counting, and data calculation
2. Batch or CONTINUOUS process control
3. Precise position/motion control
4. Open loop or feedback control, process data acquisition and display

1. Sequence control, timing, counting, and data calculation
2. Batch or continuous process control
3. Precise position/motion control
4. Open loop or feedback control, process data acquisition and display

SUPERVISORY Control and Data Acquisition (SCADA) SYSTEM is computerised hardware and software based project that provides a single integrated view of all control and INFORMATION resources, ENABLE engineers, supervisors, operators to view and interact with the working of an entire operation through graphical REPRESENTATION of their product process.

Supervisory Control and Data Acquisition (SCADA) system is computerised hardware and software based project that provides a single integrated view of all control and information resources, enable engineers, supervisors, operators to view and interact with the working of an entire operation through graphical representation of their product process.

Industrial process: chemical PLANTS, POWER GENERATION and DISTRIBUTION, METALLURGY etc and nuclear process: reactors, nuclear waste etc.

Industrial process: chemical plants, power generation and distribution, Metallurgy etc and nuclear process: reactors, nuclear waste etc.

a. Educed site visits and callouts
b. Predictive MAINTENANCE which allows proactive RATHER than REACTIVE planning
c. The ability to VIEW and adjust set points remotely
d. Reliability and robustness
e. MAXIMIZE productivity
f. Improve product quality
g. Reduce your operating and maintenance costs
h. Integrate with your business systems
i. Preserve your capital investment

a. Educed site visits and callouts
b. Predictive maintenance which allows proactive rather than reactive planning
c. The ability to view and adjust set points remotely
d. Reliability and robustness
e. Maximize productivity
f. Improve product quality
g. Reduce your operating and maintenance costs
h. Integrate with your business systems
i. Preserve your capital investment

CIMPLICITY is a SCADA package. It is based on a client server ARCHITECTURE consisting of servers and viewers. Servers are responsible for the COLLECTION and distribution of data. Viewers connect into servers and have full access to the collected data for viewing and CONTROL actions.

CIMPLICITY is a SCADA package. It is based on a client server architecture consisting of servers and viewers. Servers are responsible for the collection and distribution of data. Viewers connect into servers and have full access to the collected data for viewing and control actions.

Supervisory CONTROL and Data ACQUISITION (SCADA) system is computerised hardware and software based project that provides a single integrated view of all control and information resources, ENABLE engineers, supervisors, OPERATORS to view and INTERACT with the working of an entire operation through graphical representation of their product process.

Four editors:

a. Inkscape SAGE - SCADA Animation Graphic Editor
b. Generic Logic
c. TRACE MODE
d. UCanCode

Supervisory Control and Data Acquisition (SCADA) system is computerised hardware and software based project that provides a single integrated view of all control and information resources, enable engineers, supervisors, operators to view and interact with the working of an entire operation through graphical representation of their product process.

Four editors:

a. Inkscape SAGE - SCADA Animation Graphic Editor
b. Generic Logic
c. TRACE MODE
d. UCanCode

DCS is used for INTERFACING and computing functions and ALSO provides the means of communication between the other devices. It consists of local control unit, low level interface, HIGH level interface, SHARED communication facility Etc.

DCS is used for interfacing and computing functions and also provides the means of communication between the other devices. It consists of local control unit, low level interface, high level interface, shared communication facility Etc.

LOCAL control unit is the small collection of hard WARE in the system that can do closed LOOP control. Local control unit interfaces DIRECTLY to the process.

Local control unit is the small collection of hard ware in the system that can do closed loop control. Local control unit interfaces directly to the process.

Flexibility of CHANGING the control configuration Ability to USE the controller without being a computer EXPERT. Ability to bypass the controller in CASE it fails. So that the process still can be controlled manually. Ability of the LCU to communicate with other LCUs and other elements in system.

Flexibility of changing the control configuration Ability to use the controller without being a computer expert. Ability to bypass the controller in case it fails. So that the process still can be controlled manually. Ability of the LCU to communicate with other LCUs and other elements in system.

1. Modular design
2. Increased reliability
3. Lower cost
4. Compact size
5. Ease of programming
6. RUGGED construction and DESIGNED to withstand vibrations, temperature, HUMIDITY and noise
7. Ability to communicate with computer

1. Modular design
2. Increased reliability
3. Lower cost
4. Compact size
5. Ease of programming
6. Rugged construction and designed to withstand vibrations, temperature, humidity and noise
7. Ability to communicate with computer

Programmable LOGIC CONTROLLERS are industrially hardened micro computers, DESIGNED to replac e electromechanical RELAYS, USED to control machines and processes.

Programmable Logic Controllers are industrially hardened micro computers, designed to replac e electromechanical relays, used to control machines and processes.

The sequential OPERATION of the controller that goes through the ladder diagram from top to bottom of the ladder. In this PROCESS it updates all the outputs corresponding to the inputs. SCAN takes place from LEFT to right of each rung. Usually SCAN time is in milliseconds and it is a CONTINUOUS process.

The sequential operation of the controller that goes through the ladder diagram from top to bottom of the ladder. In this process it updates all the outputs corresponding to the inputs. SCAN takes place from left to right of each rung. Usually SCAN time is in milliseconds and it is a continuous process.

CPU is the brain of the system and CONSISTS of Microprocessor: To carry out arithmetic and logical OPERATIONS

Memory: The area in the CPU in which the information is stored and retrieved

Power Supply:The ELECTRICAL supply that converts the ac VOLTAGE to various DC operating voltages.

CPU is the brain of the system and consists of Microprocessor: To carry out arithmetic and logical operations

Memory: The area in the CPU in which the information is stored and retrieved

Power Supply:The electrical supply that converts the ac voltage to various DC operating voltages.

The GENERAL LANGUAGE program consists of Ladder Diagrams. Relay logic control scheme is represented in Ladder diagrams. Alternative LANGUAGES uses Boolean representation of these control schemes as base of the COMPUTER representation.

The general language program consists of Ladder Diagrams. Relay logic control scheme is represented in Ladder diagrams. Alternative languages uses Boolean representation of these control schemes as base of the computer representation.

PLCs are highly RELIABLE, easily programmable, Small and Inexpensive, PLCs can be designed with the communication capabilities so they can converse with the local or remote computer, They can SUSTAIN in ROBUST ENVIRONMENT less MAINTENANCE.

PLCs are highly reliable, easily programmable, Small and Inexpensive, PLCs can be designed with the communication capabilities so they can converse with the local or remote computer, They can sustain in robust environment less maintenance.

1. INPUT Interface
2. MEMORY Section
3. CENTRAL Processing UNIT (CPU)
4. Programmable Language
5. Programming tool
6. An output Interface