Date post: | 12-May-2015 |
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Automation Basics
ByRaj Nayak
(Technical Analyst)
Objectives:
• To get overview about automation .• To know about basic elements involved in the
automation process• To know how automation has been working in
the domestic and industrial spheres.• To understand how communication has helped
in automation of many things.• To understand advantages and limitations of
automation
What one will learn ?
• What are the basic elements of Automation ?• Why automation is necessary ?• What are the different technologies available for
the automation.?• Where automation exists ?• What are the different controllers ?• What is SCADA and DCS ?• How communication is playing a vital role in the
process of Automation ? • What are the different protocols used in
Automation?
Contents:• What is Automation…Role of Automation in the different industries• Why Automation ? ( Advantages)• Basic elements of Automaton … Sensors LVDT,Thermostat,Thermistor ,pressure CT,PT, Limit switches,Magntic Pick Up,Capacitive sensors etc Controllers and controller based systems Actuators Relays. Solenoids. • Types of Controllers Proportional,PI ,PID, Categories of controllers• DCS & SCADA… What is SCADA • How communication has enhanced automation. Common Protocols CAN ,MODBUS,PROPHI, Substation automation
protocol 61850 • When to go for Automation ?• Design of Automation system• Limitations / Disadvantages of Automation• Automation Myths… Impact of Automation How automation affects economics ?• Queries
What is Automation ?
• The dictionary defines automation as “The technique of making an apparatus, a process, or a system operate automatically.”
• Automation federation define automation as
“ The creation and application of technology to monitor and control the production and delivery of products and services.”
• Automation means use of Available technologies to reduce the need of Human work.
• Automation is a step beyond mechanization. Mechanization provides human
operators machinery to assist themselves with the muscular requirements of work……
WhileAutomation greatly decreases the need
for human sensory and mental requirements as well. .
Quality
Productivity
Manpower CostPlant
Total Automation Manufacturing Competitiveness Solution
Automation: Automation is basically the delegation of human control function to technical equipment for
Automation cycleSense the Inputs
Process the Logic
Give the Outputs
Outputs
Machineor
Process
Controller
Inputs
History of Automation
Manual control
Pnumatic control
Hard wired Logic Control
Electronic control using Logic gates
Programmable logic controller
Microcontrller based embedded controllers
Cluster of controllers and Master controller at Remote end.
Modern world
Ancient world
Major Mile stones in Technologies
• Ancient world ( 8000BC to 330 )• The middle age through 1599• The age of scientific
revolutions 1600-1790• The industrial Revolution 1700-1920• The electrical age 1891 to 1934• The atomic and electronic age
1935 – into 21st century out of which last 20 years belong to COMMUNICATION and INFORMATION ERA
• Invention of Wheel• Discoveries of various metals • Invention of Glass• Discovery of Electricity• Invention of Telegraphy
/Telephone• Invention of Electric Motor• Invention of Transistor 1948• Invention of Microprocessor• Invention of Mobile
Technology• Invention of Internet
Technology
Range of Technologies involved in AUTOMATION
Automation involves a very broad range of technologies including 1. Robotics 2. Expert systems(an expert system is a computer system that emulates the decision-
making ability of a human expert )3 Telemetry and communications4 Electro-optics Electro-optics is a branch of technology involving components,
devices and systems which operate by modification of the optical properties of a material by an electric field.
5 Cyber security, ( protecting your personal information or any form of digital asset
stored in your computer or in any digital memory device) 6 Process measurement and control,7 Sensors, 8 wireless applications, systems integration, test measurement, and
many, many more.
ROBOTICS
Where Automation exists ?
Automation encompasses many vital elements, systems, and job functions.
• Manufacturing , including food and pharmaceutical, chemical and petroleum, pulp and paper
• Transportation , including automotive, aerospace, and rail• Utilities , including water and waste water, oil and gas, electric
power, and telecommunications• Defense• Facility operations , including security, environmental control,
energy management, safety, and other building automation• …..And many others
AUTOMATION IS EVERYWHERE
Automation is in all functions and places
• Aerospace• Automotive• Chemical and Petroleum• Computer Technology• Construction and Design• Electro-Optics• Environmental• Food and Pharmaceutical• Glass and Ceramics• Management• Marketing and Sales• Mining and Metals
• Mining and Metals• Nuclear• Power Distribution• Process Measurement and
Control• Pulp and Paper• Robotics and Expert Systems• Safety• Sensor Technology• Systems Integration• Telemetry and
Communications• Test Measurement• Textiles• Water and Waste water• Wireless Application• .
Impact of Automation:
• Automation has a significant impact in the wide range of industries including Manufacturing industries
• Automation has been responsible for the shift in the world economy from industrial jobs to service jobs in the 20th and 21st centuries.
• Once omnipresent telephone operators have seized to exist as telephone exchanges are automated.
• ATM have reduced the need for bank visits to obtain cash and carry out transactions.
Impact of Automation:
• As a result of increase in Automation and (which is ever increasing almost every field as a result of ease in use of new Technologies)
the nature of jobs is getting affected .
• Telephone operators• Stock market agents• Railroad brake signal and
switch operators• Shoe and leather workers• Photographic process
workers and processing machine operators
• Model makers and pattern makers
How much Automation ?
• Automation represents one of the major trends of 20th century as in many cases automation has provided extended system functionality well beyond existing human capabilities.
• Contrary to the implication of the term “Automated” humans have remained a critical part of most automated systems as most automation has been piece meal covering certain functions but not all functions.Human beings have remained in the system as integrators…monitoring the automation for some functions and performing others themselves
• Full automation of the task may be technically possible but it maynot be desirable if the performance of the joint human- machine system is to be optimized.Intermediate levels of Automation may be preferable for certain tasks in order to keep human operators’ situation awareness at a higher level and allow them to perform critical functions
Level of Control
• One way to minimize the negative effect of Automation is to devise implementation schemes that keep human beings actively involved in the decision making loop while simultaneously reducing the load associated with doing everything manually
Levels of control and Automation: (adapted from Endsley and kiris,1995)
LEVEL OF AUTOMATIONROLE
HUMAN SYSTEM
NONE 1 Decide Act ---
Decision support 2 Decide Act Suggest
Consensual Artificial intelligence (AI) 3 Concur Decide Act
Monitored AI 4 Veto Decide Act
Full automation 5 --- Decide Act
1 Manual system
5 Fully automatic system
EXAMPLES OF AUTOMATION
Common Examples of AutomationDay to Day life• ATM• Starting of the vehicle • Automatic washing
Machine• Electrically driven Pump• UPS, Canopy (power
supply Back up
Industry
• Painting Robots in the automobile mfg industry
• Soldering Machines• DCS Distributed
Control Systems• SCADA• AMF Generators
Technologies involved in the working of ATM
• Computer and Electronics (HMI )• Communication using TCP/IP ( Communication with server at
remte end)• Sensors (magnetic sensor to read data from the card) Camera ,Timer
• Electromechanical solenoids and actuators (for counting currency accurately , and giving the same to user.)• Printer … Printing technology
• Home Automation
Subsystems of Home Automation:
• Hot water systems. • Appliances. Systems • Home office, home entertainment and other electronic
equipments. • Lighting. • Heating and cooling/air conditioning systems. • Fans and air pumps/heat shifters. • Powered window blinds, shutters and awnings. • Powered vents and window openings. • Water pumps, pool pumps . • Garage doors. • Security systems.
Why Automation is required ?
• Increase in comfort
• More safety
• Improve the quality and precision.
• To do the job for which human beings will not have the capacity.
• To avoid monotonous work
•Sensors•Controllers•Actuators• HMI• Display & alarm•Communication Protocol
Basic Elements of Automation
•Sensors
•Controllers
•Actuators
• HMI
• Display & alarm
Basic Elements of Automation
Sensors
• What is a sensor ?• Sensor is a device which measures a physical
quantity .
Temperature sensor (Input to thermometer /Temperature indicator)
Level sensor input to Fuel gauge
Proximity sensor, Pressure sensor
Photoelectric sensor LDR / opto coupler / photodiode
On/Off sensor push buttons / Relays /
Sensors:
• sensors are used in a wide range of control systems that makes lives for people
easier, safer and more productive both at work and at home.
• Sensors extend the reach of human capabilities so that we can save energy, make faster decisions and perform tasks with greater precision.
• Sensors take on highly repetitive tasks
– leaving us free to apply our intellectual and creative abilities to further improve our lives.
• How we wash our clothes and refrigerate our food OR how we drive our cars and generate energy sensors help us.
Different types of sensors
Common usage of sensors:
• Transport and case Refrigeration Systems:
Temperature sensors are used to measure the supply of air to temperature controlled compartments while immersion probes measure refrigerant temperature. Rugged sensors designed specifically for measuring refrigerant pressure are used in conjunction with variable speed compressors to improve system efficiency.
• Traffic /smart Highway
Piezoelectric axle detectors are used to collect traffic data on highways, classify vehicles for automated toll booths, as well as provide timing mechanism for speed and red light cameras.
Common usage of sensors:
• Petrol Pump
A rugged, hermetically sealed electromagnetic rotary encoder coupled to the fuel flow meter in gas pumps is used to accurately convert rotational pulses into gallons or liters dispensed.
• Printers : The drying process of ink jet printers is improved by monitoring air and paper humidity content. Measuring air and toner humidity guarantees print quality
in laser printers/copiers.
Common usage of sensors:
• Cooking System: Long life, high-temperature oven probes operate up to
300°C. The high accuracy optimizes cooking control while protecting users.
• Washer/Dryer: Low cost/low power vibration sensors measure load
imbalance to avoid "walking." Humidity or thermopile sensors are used in dryers to automatically shut off when clothes are dry, extending the life of clothes and improving efficiency.
Construction of C.T.
• C.T. has a primary coil of one or more turns of thick wire connected in series with the line whose current is to be measured.
• The secondary consist of large number of turns of fine wire, is connected across the ammeter terminals.
Working
• If a current transformer has primary to secondary current ratio of 100:5 then it step up the voltage 20 times and step down the current 1/20 times of its actual value.
• If we know the current ratio I1/I2 and the reading of a.c. ammeter, the current can be calculated.
• Current = ratio × ammeter reading
Potential transformer
• A PT is a step down transformer having many primary turns but few secondary turns.
• In step down the voltage decreases and current increases, thus voltage can be easily measured by using low range voltmeter.
• The voltage is stepped down in known ratio called voltage ratio.
Construction and working of P.T.
Construction• A potential transformer has many primary windings but
few number of secondary windings that makes it step down transformer.
• Voltmeter is connected to secondary winding usually voltmeter of 150 v is suitable.
Working• Primary terminals are connected across the line to which
the voltage is to be measured.• The voltmeter gives the transformed value of voltage at
secondary.• The deflection of voltmeter when divided by transformed
ratio gives the actual voltage at primary.
• Line voltage = deflection / trasf. Ratio
Where transformation ratio = V2/V1
Types of P.T.
• Some types of p.t. are
1. Shell type
2. Dry type
3. Oil type
Rating Type
below 5000 v Shell type
5000-13800 v Dry type and oil type
above 13800 v only oil type
Precaution for For CT & PT
• Utmost care should be taken to ensure that CT secondary is never opens.
• For safety purpose the secondary should be completely insulated from the high voltage primary and should be in addition grounded.
Automation and electricity demand
• In the near future, home automation systems may be linked to the electricity utility in a number of ways. The utility may communicate variations in electricity prices to a ‘smart’ electricity meter, that will interface with the home automation controller.
• Householders can then program appliances to reduce power or switch off altogether during high price periods.
• Alternatively householders could enter a supply contract that allows the electricity supplier to signal equipment controlled by the home automation system (such as air conditioners) to turn off certain equipment for short periods.
• The householder may choose to participate and obtain lower electricity prices or other financial incentives.
Desirable Sensor attributes
• Reliability
• Accuracy and Repeatability • Good response time.
• Withstanding capability.
• Long Life
• Less expensive
Repeatability and accuracy
Not repeatableNot accurate
Not repeatableAccurate
RepeatableNot accurate
RepeatableAccurate
What is difference between sensor and a transducer?
• SENSOR and TRANSDUCER both are actually sensors, but:
TRANSDUCER: convert one form of energy into ELECTRICAL energy
SENSOR: convert one form of energy into any other form of energy
Commonly used sensors for industrial
applications Information from the
sensor / Transducer can be in two forms
• Analog
• Digital
• LVDT• Pressure Transducer• Strain Gauge sensor• Magnetic sensors• Piezoelectric sensors• Photoelectric sensors• Limit switches• Relays (Relay contacts• Auxiliary contacts of
switch/ contactor /breaker
SENSORS used in the Industry
• Thermocouples• Proximity sensors• Limit switches• RPM sensor• CT /PT Current and voltage Transformer• Rogowski coil• 4-20 mA Transducers (current
voltage,frequency,KW,KVA,KVAR,PF,Phase angle)
•Sensors
•Controllers•Actuators
• HMI
• Display & alarm
Basic Elements of Automation
What is a controller ?
• A controller is a device which monitors and affects the operational conditions of a given system.
• A controller is a transfer element which compares the feedback value received from a transducer (sensor) to a predetermined value (i.e. set-point) and processes it in such a way that a control signal is transmitted in the form of an appropriate variable to the actuating element .
• Anything which is controllable must be measurable and comparable
• Comparator compares a given value with a set value
• The simplest controller is a comparator.
What is a controller ?
• A device which accepts the inputs , measure them and depending on the predetermined conditions actuate one or more devices is called the controller.
• Input signal which represents certain physical quantity can be digital or analog in the nature
• An information from the sensor is to be converted into electrical form by signal conditioners and amplifiers before it is processed by the controller
• If the information is analog then a suitable ADC is used to enable controller read information
Programmable Automation Controller
• A programmable automation controller (PAC) is a compact controller that combines the features and capabilities of a PC-based control system with that of a typical programmable logic controller (PLC). PACs are most often used in industrial settings for process control, data acquisition, remote equipment monitoring, machine vision, and motion control. Additionally, because they function and communicate over popular network interface protocols like TCP/IP, OLE for process control (OPC) and SMTP, PACs are able to transfer data from the machines they control to other machines and components in a networked control system or to application software and databases.
• [edit]PAC Origins
Types of controllers
Controllers can be categorized based on 1 Parameter Or physical quantity they are controlling Examples Temperature controller,RPM controller, Pressure controller etc 2 The manner in which they are controlling the Physical quantity Proportional controller P Proportional Integral controller PI Proportional Integral derivative Controller PID ON –OFF (Bang Bang) Controller 3 Analog or Digital controller 4 The device used for controlling { PLC , PC ( computer), Digital circuits using comparators }
• Controllers used for building automation can be grouped in 3 categories.
1. Programmable Logic Controllers (PLCs)2. , System/Network controllers, and 3. Terminal Unit controllers.
• PLCs provide the most responsiveness and processing power, but at a unit cost typically 2 to 3 times that of a System/Network controller intended for BAS applications.
Terminal Unit controllers are usually the least expensive and least powerful.
Types of Controller
• ON OFF controller
a bang–bang controller (on–off controller), also known as a hysteretic controller, that switches abruptly between two states.
(also called a Bang- bang Controller)
• Bang–bang controls frequently arise in minimum-time problems.
• For example, if it is desired to stop a car in the shortest possible time at a certain position sufficiently far ahead of the car….. the solution is to apply maximum acceleration until the unique switching point, and then apply maximum braking to come to rest exactly at the desired position.
• This solution, which can be "uncomfortable" for the passengers, is a bang–bang solution: maximum engine throttle followed by maximum braking.
• A familiar everyday example is bringing water to a boil l in the shortest time, which is achieved by applying full heat, then turning it off when the water reaches a boil.
Controller
• Controllers are essentially small, purpose-built computers with input and output capabilities.
• These controllers come in a range of sizes and capabilities to control devices commonly found in buildings, and to control sub-networks of controllers.
• Inputs allow a controller to read temperatures, humidity, pressure, current flow, air flow, and other essential factors.
• The outputs allow the controller to send command and control signals to slave devices, and to other parts of the system.
• Inputs and outputs can be either digital or analog
MicroProcessor and Microcontroller
• Microprocessors are these days replaced by Microcontrollers
Selection Criteria for Controller:
• Speed• Memory• I/O handling capability• Communication capability• Built in Features
in Built ADC
in built DAC
Intel seriese of processors & Operating systems:• 4004• 8008• 8080• 8085• 8086• 80186• 80286 PC XT• 80386 PC• 80486-Dx2• 80486-Dx4• Pentium • P3• P4• 32 bit processors
• Linux / VariantsMacOSMS-DOSIBM OS/2 WarpUnix / VariantsWindows CEWindows 3.xWindows 95Windows 98Windows 98 SEWindows MEWindows NTWindows 2000
Windows XPWindows VistaWindows 7
Programming:• A controller chip without a S/W
loaded in it has little power to control.
• A controller understands only zeros and ones (in fact it doesn't even understand zeros and ones …it can only distinguish two levels …low and High
• The lowest level language is Machine language which has only two characters . The morse code is perhaps the best example of machine language
Assembly level language depends on the type of the controller …each contrller will have a fixed number of instruction set.
• Highest level languages are those in which human beings communicate..
• There are many higher level languages depending on the type of application for which they are used.
Examples are FORTRAN COBOL BASIC FOXPro
Compilers and Assemblers
• C
• C++
• Java
Programming the controllers:
• Controller without programming has no value
Programming Languages Higher level Languages
C,C++.Java,Visual Basic
Assembly languages Controller specific Machine language Will have series of zeros
and ones (morse code is the best
example)
Types of Instructions
• I/O Handling
• Assigning
• Mathematical
• Logical
• Repetitive
• Branching
• A building Automation system (BAS)
Industrial Automation Process Control System:
• In practice, an industrial automation process control system can be characterized as one or more of the following:
I. Batch processingII. Continuous processingIII. Discrete
Batch processes are used to produce a relatively low to intermediate quantities of product.
BATCH processingApplications that require specific quantities of raw materials combinedin specific ways for particular durations to produce an
intermediate or end result. Examples 1 production of adhesives and
glues, (which require the mixing of raw materials in a heated vessel for a period of time to form a quantity of end product.
2 Production of food, beverages and medicine.
3 PCB assemblies
Continuous and Discrete Systems:
II. Continuous – Continuous processes used in
industrial automation applications produce very large quantities of product.
Examples The control of the water
temperature in a heating jacket, is an example of continuous process control. Some examples of continuous processes are the production of fuels, chemicals and plastics.
3 Discrete –
Found in manufacturing, motion and packaging applications.
Examples : Robotic assembly,
commonly found in automotive production, can be characterized as discrete process control.
Most discrete manufacturing involves the production of discrete pieces of product, such as metal stamping.
Supervisory control & Data Acquisition (SCADA)
SCADA refers to a system that collects data from various sensors at a factory, plant or in other remote locations and then sends this data to a central computer which then manages and controls the data.
SCADA focuses on gathering and circulating the right amount of system information to the right person or computer within the right amount of time.
DCS and SCADA• DCS is a very broad term used in a variety of industries, to monitor and
control distributed equipment.
• SCADA is an acronym for Supervisory Control And Data Acquisition. SCADA systems perform data collection and control at the supervisory level. Some systems labeled as SCADA perform data acquisition only.
• A SCADA system should not be critical to the controlled process. The SCADA connects to a PLC or real time device, so there is a separate or integrated real-time automated control system that responds quickly enough to compensate for process changes within the time constants of the process.
• The SCADA controls and monitors the process, but the process must also run independently from the SCADA system in case of failure.
Features of SCADA
Features of typical SCADA software
• Dynamic process graphic• Real-time and Historical
trending• Alarms• Recipe Management• Security• Device connectivity• Database connectivity
Role of communication in Automation:
• Communication has played a vital role in the process of Automation
• The controller receives the inputs from various sensors and also receives the inputs from the communication bus.
• Master control is usually at centralized location and in it must receive data from all the locations to enable it to to process the inputs and reach to the decision
• Different protocols are used to transfer the data to the controller
Different Protocols
• IEEE Instrumentation BUS
• CAN Bus
• Modbus
• Prophi Bus
• 61850 Protocol
• TCP/IP
Different Protocols
• IEEE Instrumentation BUS
• CAN Bus
• Modbus
• Prophi Bus
• 61850 Protocol
• TCP/IP
•Sensors•Controllers
•Actuators• HMI
• Display & alarm
Basic Elements of Automation
What is an actuator ?Definition for actuator:a mechanism that puts
something into automatic action .• An actuator is a
mechanical device for moving or controlling a mechanism or system.
• An actuator is operated by a source of energy, usually in the form of an electric current, hydraulic fluid pressure or Pneumatic pressure , and converts that energy into some kind of motion.
•
Different actuators used to control the given system
• Relay• Solenoid• Valve• Motor• MHT• Contactor
In addition to above types of actuators a system can be controlled by a digital signal (flag )generated locally or received from remote end device through communication channel using a certain protocol for the communication
Actuators
Actuators can be categorized based on
1. Energy source used– electrically operated– Pneumatically operated– Hydraulically operated– Gas operated
2. Type of Motion Linear motion Rotary motion Oscillatory motion
• Perhaps the most common type of actuator is powered by air — the pneumatic cylinder, also known as the air cylinder
. Air cylinders are air-tight cylinders, typically made from metal, that use the stored energy of compressed air to move a piston when the air is released or uncompressed. They are most commonly used in manufacturing and assembly processes.
Grippers, which are used in robotics, use actuators that are driven by compressed air to work much like human finger
RELAY:
• Relay is an electromechanical device and has a predesigned operating voltage.
• Essentially it has a coil,a plunger,a spring and atleast one pair of sands operations coil gets energized and electromagnetic action as aresult of current flow in the coil attracts the plunger resulting in the change of contact position.
• Contacts are designed to carry large current compared to the operating current of the coil.Contact material can withsatnd several thousands operations
• The relays are available in different types (sealed,Unsealed) latching /non latching and ac/dc operating voltages, The contacts available in the relays are N/O .N/c or C/O types.
Relay and Contactor:
• Contactor again works on the same principle however contactor has two types of contacts ….Main contacts and auxiliary contacts. Auxiliary contacts are used to give the status to the controller while main contacts carry the controlled current.
• Contactors are available in different sizes depending on the current carrying capability of the main contacts
Solenoid:
• A solenoid also operates on the principle of electromagnetism like relay however in addition to changing the status of the contacts solenoid plunger movement also initiates mechanical movement leading to change in the positions of other mechanical components to control the pnematic Hydraulic or electrical circuits.
• Stepper Motors• Used for measured
rotationCan be held at a
particular position of the shaft
Ideal for many autonomous robots requiring higher precision
• Servo Motors :Used in closed loop control
systems in which work is the control variable.
An integral feedback device (resolver) or devices (encoder and tachometer) are either incorporated within the servo motor or are remotely mounted, often on the load itself
Double acting actuator• A double acting actuator is a mechanical device designed to supply powered bi-
directional actuation for secondary mechanisms. This is in contrast to single action or spring return actuators and solenoids, which feature a powered stroke in one direction only and rely on a secondary source of energy to reset or return the actuator. The double acting actuator is typically driven by electric motors or compressed oil and gas. Electrically-driven double action actuators supply their bi-directional force by means of a motor reversing control circuit. Compressed gas and oil actuators feature opposed inlet valves that direct the motive agent to one side or the other of the actuator mechanism.
• Actuators are devices used to operate a machine or mechanism remotely by supplying a predetermined range of powered output movement. This movement is generally broken down into two strokes in opposed directions. These may be activation and recovery strokes or bi-directional operating strokes. Activation and recovery systems are well-illustrated by a metal stamping machine where the die is pushed down for the activation stroke and recovered, or returned, to a neutral position in readiness for the next cycle. A bi-direction output may be seen in a valve actuator, which turns in one direction to open the valve and in the opposite direction to close it.
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Summary• Automation has a wide spread presence in almost every industry and
homes• Automation systems consist of sensors controllers and an actuators. • There are variety of sensors depending on the physical quantity to be
controlled. In power system the most common sensors are CTs and PTs• The simplest type of controller is a comparator and the advanced controllers
are programmable and are capable of handling number of inputs and outputs. Microcontrollers and computers are widely used these days in the automation.
• Controllers must be programmed for the given sets of Inputs and outputs to get the desirable results. All the intelligence is embedded in the controller after programming in higher level languages and using suitable compilers.
• There are different types of actuators controlling linear and rotational motion and the most common actuators are Solenoids ,Relays and Motors
• Communication plays a very important role in the Automation system and depending on the application a particular Protocol is used. Internet technology has revolutionized the automation. In Substation Automation 61850 protocol is used for acquiring data .
• Automation has many advantages including making our lives comfortable and enable human beings to do the things which otherwise would have been impossible to do manually with same efficiency and accuracy.
• Automation changes the nature of jobs and demands new skills and it is a myth that it leads to unemployment…It has shifted the focus from Manufacturing industries to the Service related industries
Questions from the Audiance
THANKS
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