CHAPTER-1

INTRODUCTION

1.1 COMPANY PROFILE

Merino laminates market presence in over 60 countries and their extensive quality is

making multi-products with a world class standards .Merino Laminates the world’s

leading manufacturer and exporter of decorative laminates for the interiors segment.

They showcase a range of world class, premium laminates with more than 10,000

designs, textures, colors and finishes. Complementary products from the Merino

Group include plywood, melamine-faced particle board and post-formed panels for

the interiors industry. They have committed themselves to uphold the highest

manufacturing standards, a practice that has earned all our facilities pertinent

certifications that include ISO 9001, ISO 14001 and OHSAS 18001.

The Merino Laminates brand came into existence in 1981, when the Merino Group

extended its activity to laminates manufacturing, having entered the interiors segment

with Plywood in 1974. About the Merino Group: Founded in 1968, the Merino Group

is today a US$ 165 million group with diverse business interests which include Panel

& Panel Products, Biotechnology (Agriculture & Food Processing) and Information

Technology (IT). They are driven by their constant effort to maintain Economy,

Excellence and Ethics in all our businesses. They export to 60 countries around the

globe, and employ 3000 people across three manufacturing sites, 19 offices in India

and an office in the U.S.

1.2 CORPORATE PHILOSOPHY

Our business is built on the steady pillars of a globally relevant mission ,a far reaching

vision ,a strong three-pronged motto.

a) Mission: Universal Weal through Trade & Industry

b) Vision: Global Competence & Global Competitiveness Synergizing Work Culture

and ethos.

c) Motto: Economy, Excellence, Ethics and explanation of this Motto: Excellence in

1

economy is founded on work ethics, sustainable, when nourished by Moral Ethics.

d) Business Strategy: Business approach is Market Driven, Knowledge Based,

System Sustained, I.T Enabled, and Ethics Anchored.

Inspiration:

"Arise, Awake and Stop Not till the Goal is Reached" - Swami Vivekananda

1.3 HISTORIC FACT

Incorporated as a private limited company in 1965 under the name N H Lohia

(Agencies) Pvt. Ltd, Century Laminating Company acquired its present name in 1984.

It became a deemed public limited company in 1988 and a public limited company in

1995. The company was promoted by M K Lohia, Merino Panel Products is a

subsidiary of the company. The company exports through Merino Exports Pvt. Ltd, its

group company. The company manufactures decorative laminates at its plant in

Achheja (Ghaziabad district), Uttar Pradesh, which are sold under the Merino brand

name. It’s cold storage and ice plant is located in New Delhi.

Fig 1.1 Merino panels and products ltd (ncr,delhi- rohtak road)

Fig 1.1 shows the location of the industry, In Aug.'94, the company set up a 6000 tpa

formaldehyde manufacturing plant as a backward integration. Formaldehyde is used

for the preparation of resins which is required in the manufacture of laminates. In

1994-95, the installed capacity of the laminating plant was increased from 42.50 lac

sq mtr to 80 lac sq mtr. In Sep.'95, it came out with a public issue to part-finance the

expansion-cum-modernisation programme involving the laminating capacity increase

2

from 80 lac sq mtr to 108 lac sq mtr. During 2000-2001 company obtained ISO-

9002:1994 certification from DNV the Netherlands, in its branches at Kolkata,

Mumbai, Bangalore, Chennai, Delhi, Pune, Nagpur and Ahmedabad. The Installed

Capacity of Decorative laminates has increased from 80 lac Sq Mtrs to 108 lac Sq

Mtrs. In 2001-02 the installed capacity of Decorative laminates was increased to 167

lacs Sq Mtrs.

1.4 INFRASTRUCTURE INTEGRATION

The Merino Group's facilities are state-of-the-art, geared for integration, and

strategically well-located to serve the markets. Its two manufacturing facilities for

High Pressure Laminates have a combined annual production capacity of 35million

sq.m. Our three short cycle lamination facilities can produce pre-laminated particle

and MDF boards in sizes varying from 2.5 X 6 ft up to 9 X 6 ft. Following the

principle of Economy, their three pre-lamination lines are located in northern and

southern locations for readier dispatches to the customer. In keeping with their

integrated approach, industry have set up a printing facility to offer custom designs. A

plate polishing and cleaning facility has also been installed for uniform surface finish

of stainless steel moulds. The only HPL manufacturer in Asia to have chroming and

de-chroming facility that maintains chromed SS moulds in order to produce non-

directional chromed gloss plates. Industry manufactures own formaldehyde and resins

too. Offices and warehouses in all major state capitals ensure an adequate presence of

Merino and serve to expedite business decisions and logistics. Further, an in-house

fleet of vehicles ensures on-time product delivery at all times.

1.5 CERTIFICATES AND ACCREDITATION

Industry encourage adherence to safety standards, promote ease of application, strive

to reduce installation time, and help customers to maintain their interiors better with

usage information. At Merino, quality is a tradition that is followed meticulously and

in its entirety. Their commitment to the highest standards in manufacturing process

has won certifications including ISO 9001, ISO 14001 and ISO 18001, for all

facilities. Merino has integrated all the stages of its operation through ERP, ensuring

transparency and on-time information to customers and service providers. A dedicated

and focused Research and Development team works unremittingly towards

3

continuous innovation and improvement, resulting in an array of superior quality

products. Moreover, experts from around the world are invited to strengthen

knowledge base.

Fig 1.2 Certification standards

a) DECORATIVE LAMINATE: Decorative laminates are laminated products

primarily used as furniture surface materials or wall paneling. It can be

manufactured as either high or low pressure laminate, with the two processes

not much different from each other except for the pressure applied in the

pressing process.

b) HIGH PRESSURE LAMINATE: According to McGraw-Hill Dictionary of

Architecture & Construction, high-pressure laminates consists of laminates

"molded and cured at pressures not lower than 1,000 per sq in.(70 kg per sq

cm.)

c) LOW PRESSURE LAMINATE: Low Pressure laminate is defined as "a

plastic laminate molded and cured at pressures in general of 400 pounds per

square inch (approximately 27 atmospheres or 2.8 x 106 pascals).

4

Fig1.3 multiple products

As shown in Fig 1.3 merino multiple products are shown which are manufactured at

their various units, various laminates types described above are used in interior

solutions and also the food products are launched by them in market which are

showing good results.Some quality standards of laminates are mentioned below:

ANTI-BACTERIAL: Antibacterial properties are important for decorative laminates

because these laminates are used as kitchen tops and counter tops, cabinets and table

tops that may be in constant contact with food materials and younger children.

Antibacterial properties are there to ensure that bacterial growth is minimal. One of

the standards for Anti-Bacterial is the ISO 22196:2007, which is based on

the Japanese Industrial Standards (JIS), code Z2801. This is one of the standards most

often referred to in the industry with regards to tests on microbial activities

(specifically bacteria) and in the JIS Z2801, two bacteria species are used as a

standard, namely E.Coli and Staphylococcus aureus. However, some companies may

have the initiative to test more than just these two bacteria and may also replace

Staphylococcus aureus with MRSA, the methicillin-resistant version of the same

bacteria. Again, different countries may choose to specify different types of microbes

for testing especially if they identified some bacteria groups which are more

intimidating in their countries due to specific reasons.

5

ANTI-FUNGI: A common anti-fungi standard is the ASTM G21. Not all

manufacturers will take the initiatives for product R&D for anti-Fungi attributes.

Manufacturers like Mica Laminates send their products for laboratory tests for

certification following the ASTM G21-09 standard, while Formica partners with

Microbian Protection, which is a company manufacturing additives, including the

anti-bacterial additives.

FIRE-RESISTANT AND FLAME RETARDANT: There are many different

standards with regards to fire resistant and flame retardant properties of High Pressure

Decorative Laminates.

"GREEN" CERTIFICATES: One of the internationally-acknowledged "Green"

certificates for decorative laminates is GREENGUARD. The GREENGUARD marks

are to certify that the products have low chemical emissions. Chemicals tested include

VOCs, formaldehyde and other harmful particles. The tests are based on single

occupancy room with outdoor ventilation following the ANSI/ASHRAE Standard

62.1-2007, Ventilation for Acceptable Indoor Air Quality. There are also many other

"Green" certifications, some which are requirements by the authorities before the

product can be used as building materials. These include the Singapore Green

Label which is recognized by the Global Ecolabelling Network (GEN) and all its

member countries. Industry encourage adherence to safety standards, promote ease of

application, strive to reduce installation time, and help customers to maintain their

interiors better with usage information. At Merino, quality is a tradition that is

followed meticulously and in its entirety. Their commitment to the highest standards

in manufacturing process has won certifications including ISO 9001, ISO 14001 and

ISO 18001, for all facilities. Merino has integrated all the stages of its operation

through ERP, ensuring transparency and on-time information to customers and

service providers.

6

1.6 DEPARTMENTS IN INDUSTRY

In Fig 1.4 there are various departments of industry are shown and at every level

decentralization mechanism is followed for achieving the industrial goals, focused

section was electronics and electrical which is explained further.

Fig1.4 Flow chart of departments in industry

CHAPTER-2

AUTOMATION AND INSTRUMENTATION

2.1 INTRODUCTION OF AUTOMATION

7

Automation is the use of machines, control systems and information technologies to

optimize productivity in the production of goods and delivery of services. The correct

incentive for applying automation is to increase productivity, and quality beyond that

possible with current human labor levels so as to realize economies of scale, and

realize predictable quality levels. In the scope of industrialization, automation is a step

beyond mechanization. Whereas mechanization provides human operators with

machinery to assist them with the muscular requirements of work, automation greatly

decreases the need for human sensory and mental requirements while increasing load

capacity, speed, and repeatability. Automation plays an increasingly important role in

the world economy and in daily experience.

a) Automation has had a notable impact in a wide range of industries beyond

manufacturing. Once-ubiquitous telephone operators have been replaced

largely by automated telephone switchboards and answering machines.

b) Medical processes such as primary screening in electrocardiography and

laboratory analysis of human genes, cells, and tissues are carried out at much

greater speed and accuracy by automated systems. Automated teller machines

have reduced the need for bank visits to obtain cash and carry out transactions.

In general, automation has been responsible for the shift in the world economy

from industrial jobs to service jobs in the 20th and 21st centuries.

c) The term automation, inspired by the earlier word automatic was not widely

used before 1947, when General Motors established the automation

department. At that time automation technologies were electrical, mechanical,

hydraulic and pneumatic. Between 1957 and 1964 factory output nearly

doubled while the number of blue collar workers started to decline

d) Automation is the use of control systems and information technologies

reducing the need for human intervention. In the scope of industrialization,

automation is a step beyond mechanization. Whereas mechanization provided

human operators with machinery to assist them with the muscular

requirements of work, automation greatly reduces the need for human sensory

and mental requirements as well. Automation plays an increasingly important

role in the world economy and in daily experience.

8

2.2 PLC SYSTEM IN AUTOMATION

A Programmable Logic Controller, PLC or Programmable Controller is a digital

computer used for automation of electromechanical processes, such as control of

machinery on factory assembly lines, amusement rides, or light fixtures. The

abbreviation "PLC" and the term "Programmable Logic Controller" are registered

trademarks of the Allen-Bradley Company (Rockwell Automation). PLCs are used in

many industries and machines. [3] Figure shows ,Siemens Simatic S7-400 system at

rack, left-to-right: power supply unit PS407 4A, CPU 416-3, interface module IM

460-communication processor CP 443-1.

Fig 2.1 Siemens Simatic S7-400

system

Unlike general-purpose computers, the PLC is

designed for multiple inputs and output arrangements,

extended temperature ranges, immunity to

electrical noise, and resistance to vibration and

impact. Programs to control machine operation are

typically stored in battery-backed-up or non-volatile memory. A PLC is an example

of a hard real time system since output results must be produced in response to input

conditions within a limited time,[3] otherwise unintended operation will results in fig

2.1 is showing the PLC.

9

History of plc : Before the PLC, control, sequencing, and safety interlock logic for

manufacturing automobiles was mainly composed of relays, cam timers, drum

sequencers, and dedicated closed-loop controllers. Since these could number in the

hundreds or even thousands, the process for updating such facilities for the yearly

model change-over was very time consuming and expensive, as electricians needed to

individually rewire relays to change the logic. Digital computers, being general-

purpose programmable devices, were soon applied to control of industrial processes.

Early computers required specialist programmers, and stringent operating

environmental control for temperature, cleanliness, and power quality. Using a

general-purpose computer for process control required protecting the computer from

the plant floor conditions. An industrial control computer would have several

attributes: it would tolerate the shop-floor environment, it would support discrete (bit-

form) input and output in an easily extensible manner, it would not require years of

training to use, and it would permit its operation to be monitored. The response time

of any computer system must be fast enough to be useful for control; the required

speed varying according to the nature of the process. Early PLCs were designed to

replace relay logic systems. These PLCs were programmed in "ladder logic" with

reference to [1], which strongly resembles a schematic diagram of relay logic. This

program notation was chosen to reduce training demands for the existing technicians.

Other early PLCs used a form of instruction list programming, based on a stack-based

logic solver. The ladder logic to programming languages such as specially adapted

dialects of BASIC and C. Another method is State Logic, a very high-level

programming language designed to program PLCs based on state transition diagrams.

10

Programming: Early PLCs, up to the mid-1980s, were programmed using

proprietary programming panels or special-purpose programming terminals, which

often had dedicated function keys representing the various logical elements of PLC

programs. Some proprietary programming terminals displayed the elements of PLC

programs as graphic symbols, but plain ASCII character representations of contacts,

coils, and wires were common. Programs were stored on cassette tape cartridges.

Facilities for printing and documentation were minimal due to lack of memory

capacity. The very oldest PLCs used non-volatile magnetic core memory. More

recently, PLCs are programmed using application software on personal computers,

which now represent the logic in graphic form instead of character symbols. The

computer is connected to the PLC through Ethernet, RS-232, RS-485 or RS-422

cabling. The programming software allows entry and editing of the ladder-style logic.

Generally the software provides functions for debugging and troubleshooting the PLC

software. For example, by highlighting portions of the logic to show current status

during operation or via simulation. The software will upload and download the PLC

program, for backup and restoration purposes. In some models of programmable

controller, the program is transferred from a personal computer to the PLC through a

programming board which writes the program into a removable chip such as an

EEPROM or EPROM.

Functionality: Modern PLCs can be programmed in a variety of ways, from the

relay-derive. The functionality of the PLC has evolved over the years to include

sequential relay control, motion control, process control, distributed control systems

11

and networking. The data handling, storage, processing power and communication

capabilities of some modern PLCs are approximately equivalent to desktop

computers. PLC-like programming combined with remote I/O hardware, allow a

general-purpose desktop computer to overlap some PLCs in certain applications.

Regarding the practicality of these desktop computer based logic controllers, it is

important to note that they have not been generally accepted in heavy industry

because the desktop computers run on less stable operating systems than do PLCs,

and because the desktop computer hardware is typically not designed to the same

levels of tolerance to temperature, humidity, vibration, and longevity as the processors

used in PLCs.

2.2.1 FEATURES OF PLC

The main difference from other computers is that PLCs are armored for severe

conditions (such as dust, moisture, heat, cold) and have the facility for

extensive input/output (I/O) arrangements. These connect the PLC to sensors

and actuators. PLCs read limit switches, analog process variables (such as

temperature and pressure), and the positions of complex positioning systems.

Some use machine vision. On the actuator side, PLCs operate electric motors,

pneumatic or hydraulic cylinders, magnetic relays, solenoids, or analog

outputs. The input/output arrangements may be built into a simple PLC, or the

PLC may have external I/O modules attached to a computer network that

plugs into the PLC.[3]

a) Scan time: A PLC program is generally executed repeatedly as long as the

controlled system is running. The status of physical input points is copied to

an area of memory accessible to the processor, sometimes called the "I/O

Image Table". The program is then run from its first instruction rung down to

the last rung. It takes some time for the processor of the PLC to evaluate all

the rungs and update the I/O image table with the status of outputs. This scan

time may be a few milliseconds for a small program or on a fast processor, but

older PLCs running very large programs could take much longer to execute

12

the program. If the scan time was too long, the response of the PLC to process

conditions would be too slow to be useful. As PLCs became more advanced,

methods were developed to change the sequence of ladder execution, and

subroutines were implemented. This simplified programming could be used to

save scan time for high-speed processes; for example, parts of the program

used only for setting up the machine could be segregated from those parts

required to operate at higher speed. Special-purpose I/O modules, such as

timer modules or counter modules, can be used where the scan time of the

processor is too long to reliably pick up, for example, counting pulses and

interpreting quadrature from a shaft encoder. The relatively slow PLC can still

interpret the counted values to control a machine, but the accumulation of

pulses is done by a dedicated module that is unaffected by the speed of the

program execution.

b) User interface: PLCs may need to interact with people for the purpose of

configuration, alarm reporting or everyday control.

A human-machine interface (HMI) is employed

for this purpose. HMIs are also referred to as

man-machine interfaces (MMIs) and

graphical user interface (GUIs). A simple

system may use buttons and lights to interact

with the user. Text displays are available as well

as graphical touch screens. More complex

systems use programming and monitoring

software installed on a computer, with the PLC connected via a

communication interface.

c) Programming: PLC programs are typically written in a special application on

a personal computer, then downloaded by a direct-connection cable or over a

network to the PLC. The program is stored in the PLC either in battery-

backed-up RAM or some other non-volatile flash memory. Often, a single

PLC can be programmed to replace thousands of relays.

13

Fig 2.2 Control panel with PLC

Under the IEC 61131-3 standard, PLCs can be programmed using standards-

based programming languages. A graphical programming notation called

Sequential Function Charts is available on certain programmable controllers.

Initially most PLCs utilized Ladder Logic Diagram Programming, a model

which emulated electromechanical control panel devices (such as the contact

and coils of relays) which PLCs replaced. This model remains common today.

Fig2.2 shows control panel with PLC (grey elements in the center).The unit

consists of separate elements, from left to right; power supply, controller, relay

units for in- and output.

2.2.2 PLC COMPARED TO OTHER CONTROL SYSTEMS

PLCs are well adapted to a range of automation tasks. These are typically industrial

processes in manufacturing where the cost of developing and maintaining the

automation system is high relative to the total cost of the automation, and where

changes to the system would be expected during its operational life. PLCs contain

input and output devices compatible with industrial pilot devices and controls; little

electrical design is required, and the design problem centers on expressing the desired

sequence of operations. PLC applications are typically highly customized systems, so

the cost of a packaged PLC is low compared to the cost of a specific custom-built

controller design. On the other hand, in the case of mass-produced goods, customized

control systems are economical. This is due to the lower cost of the components,

which can be optimally chosen instead of a "generic" solution, and where the non-

recurring engineering charges are spread over thousands or millions of units. For high

volume or very simple fixed automation tasks, different techniques are used. For

14

example, a consumer dishwasher would be controlled by an electromechanical cam

timer costing only a few dollars in

production quantities. A

microcontroller- based design

would be appropriate

where hundreds or thousands of

units will be produced and so

the development cost (design of

power supplies, input/output

hardware and necessary

testing and certification) can be spread over many sales, and where the end-user

would not need to alter the control. Automotive applications are an example; millions

of units are built each year, and very few end-users alter the programming of these

controllers. However, some specialty vehicles such as transit buses economically use

PLCs instead of custom-designed controls, because the volumes are low and the

development cost would be uneconomical.

Fig2.3 Allen-Bradley PLC installed in a control panel

Very complex process control, such as used in the chemical industry, may require

algorithms and performance beyond the capability of even high-performance PLCs.

Very high-speed or precision controls may also require customized solutions; for

example, aircraft flight controls. Single-board computers using semi-customized or

fully proprietary hardware may be chosen for very demanding control applications

15

where the high development and maintenance cost can be supported. "Soft PLCs"

running on desktop-type computers can interface with industrial I/O hardware while

executing programs within a version of commercial operating systems adapted for

process control needs. Programmable controllers are widely used in motion control,

positioning control and torque control. PLCs have similar functionality as Remote

Terminal Units. An RTU, however, usually does not support control algorithms or

control loops. As hardware rapidly becomes more powerful and cheaper, RTUs, PLCs

and DCSs are increasingly beginning to overlap in responsibilities, and many vendors

sell RTUs with PLC-like features and vice versa. In recent years "Safety" PLCs have

started to become popular, either as standalone models or as functionality and safety-

rated hardware added to existing controller architectures (Allen Bradley Guardlogix,

Siemens F-series etc.). These differ from conventional PLC types as being suitable for

use in safety-critical applications for which PLCs have traditionally been

supplemented with hard-wired safety relays.

2.3 INTRODUCTION TO SCADA SYSTEM

SCADA (supervisory control and data acquisition) is a type of industrial control

system (ICS). Industrial control systems [2]are computer controlled systems that

monitor and control industrial processes that exist in the physical world. SCADA

systems historically distinguish themselves from other ICS systems by being large

scale processes that can include multiple sites, and large distances. These

processes include industrial, infrastructure, and facility-based processes, as

described below:

a) Industrial processes include those of manufacturing, production, power

generation, fabrication, and refining, and may run in continuous, batch,

repetitive, or discrete modes.

b) Infrastructure processes may be public or private, and include water treatment

and distribution, wastewater collection and treatment, oil and gas pipelines,

electrical power transmission and distribution, wind farms, civil defense siren

systems, and large communication systems.

c) Facility processes occur both in public facilities and private ones, including

buildings, airports, ships, and space stations. They monitor and control

heating, ventilation, and air conditioning systems (HVAC), access, and energy

16

consumption.

Common system components, A SCADA system usually consists of the following

subsystems:

a) A human–machine interface or HMI is the apparatus or device which presents

processed data to a human operator, and through this, the human operator

monitors and controls the process.

b) SCADA is used as a safety tool as in lock-out tag-out

c) A supervisory (computer) system, gathering (acquiring) data on the process

and sending commands (control) to the process.

d) Remote terminal units (RTUs) connecting to sensors in the process, converting

sensor signals to digital data and sending digital data to the supervisory

system.

17

Fig 2.4 level control system through PLC and SCADA

e) Programmable logic controller (PLCs) used as field devices because they are

more economical, versatile, flexible, and configurable than special-purpose

RTUs.

f) Communication infrastructure connecting the supervisory system to the

remote terminal units.

g) Various process and analytical instrumentation.

The term SCADA usually refers to centralized systems as shown in Fig 2.4 which

monitor and control entire sites, or complexes of systems spread out over large areas

(anything from an industrial plant to a nation). Most control actions are performed

automatically by RTUs or by PLCs. Host control functions are usually restricted to

basic overriding or supervisory level intervention. For example, a PLC may control

the flow of cooling water through part of an industrial process, but the SCADA

system may allow operators to change the set points for the flow, and enable alarm

conditions, such as loss of flow and high temperature, to be displayed and recorded.

The feedback control loop passes through the RTU or PLC, while the SCADA system

monitors the overall performance of the loop.

18

Data acquisition begins at the RTU or PLC level and includes meter readings and

equipment status reports that are communicated to SCADA as required. Data is then

compiled and formatted in such a way that a control room operator using the HMI can

make supervisory decisions to adjust or override normal RTU (PLC) controls. Data

may also be fed to an Historian, often built on a commodity Database Management

System, to allow trending and other analytical auditing. SCADA systems typically

implement a distributed database, commonly referred to as a tag database, which

contains data elements called tags or points. A point represents a single input or output

value monitored or controlled by the system. Points can be either "hard" or "soft". A

hard point represents an actual input or output within the system, while a soft point

results from logic and math operations applied to other points. (Most implementations

conceptually remove the distinction by making every property a "soft" point

expression, which may, in the simplest case, equal a single hard point.) Points are

normally stored as value-timestamp pairs: a value, and the timestamp when it was

recorded or calculated. A series of value-timestamp pairs gives the history of that

point. It is also common to store additional metadata with tags, such as the path to a

field device or PLC register, design time comments, and alarm information. SCADA

systems are significantly important systems used in national infrastructures such as

electric grids, water supplies and pipelines. However, SCADA systems may have

security vulnerabilities, so the systems should be evaluated to identify risks and

solutions implemented to mitigate those risks.

Human–machine interface: A human–machine interface or HMI is the apparatus

which presents process data to a human operator, and through which the human

operator controls the process. HMI is usually linked to the SCADA system's databases

and software programs, to provide trending, diagnostic data, and management

information such as scheduled maintenance procedures, logistic information, detailed

schematics for a particular sensor or machine, and expert-system troubleshooting

guides. The HMI system usually presents the information to the operating personnel

graphically, in the form of a mimic diagram. This means that the operator can see a

schematic representation of the plant being controlled. For example, a picture of a

pump connected to a pipe can show the operator that the pump is running and how

much fluid it is pumping through the pipe at the moment. The operator can then

switch the pump off. The HMI software will show the flow rate of the fluid in the pipe

19

decrease in real time. Mimic diagrams may consist of line graphics and schematic

symbols to represent process elements, or may consist of digital photographs of the

process equipment overlain with animated symbols.

The HMI package for the SCADA system typically includes a drawing program that

the operators or system maintenance personnel use to change the way these points are

represented in the interface. These representations can be as simple as an on-screen

traffic light, which represents the state of an actual traffic light in the field, or as

complex as a multi-projector display representing the position of all of the elevators in

a skyscraper or all of the trains on a railway. An important part of most SCADA

implementations is alarm handling. The system monitors whether certain alarm

conditions are satisfied, to determine when an alarm event has occurred. Once an

alarm event has been detected, one or more actions are taken (such as the activation of

one or more alarm indicators, and perhaps the generation of email or text messages so

that management or remote SCADA operators are informed). In many cases, a

SCADA operator may have to acknowledge the alarm event; this may deactivate some

alarm indicators, whereas other indicators remain active until the alarm conditions are

cleared.

Alarm conditions can be explicit—for example, an alarm point is a digital status point

that has either the value NORMAL or ALARM that is calculated by a formula based

on the values in other analogue and digital points—or implicit: the SCADA system

might automatically monitor whether the value in an analogue point lies outside high

and low limit values associated with that point.

20

Fig 2.5

SCADA

System

The SCADA system as shown in Fig 2.5 is the example of water filtering system with

alarm. More examples of alarm indicators include a siren, a pop-up box on a screen,

or a coloured or flashing area on a screen (that might act in a similar way to the "fuel

tank empty" light in a car); in each case, the role of the alarm indicator is to draw the

operator's attention to the part of the system 'in alarm' so that appropriate action can

be taken. In designing SCADA systems with reference to [2] care must be taken when

a cascade of alarm events occurs in a short time, otherwise the underlying cause

(which might not be the earliest event detected) may get lost in the noise.

21

Supervisory station: The term supervisory station refers to the servers and software

responsible for communicating with the field equipment (RTUs, PLCs, SENSORS

etc.), and then to the HMI software running on workstations in the control room, or

elsewhere. In smaller SCADA systems, the master station may be composed of a

single PC. In larger SCADA systems, the master station may include multiple servers,

distributed software applications, and disaster recovery sites. To increase the integrity

of the system the multiple servers will often be configured in a dual-redundant or hot-

standby formation providing continuous control and monitoring in the event of a

server failure.

Operational philosophy: For some installations, the costs that would result from the

control system failing are extremely high. Hardware for some SCADA systems is

ruggedized to withstand temperature, vibration, and voltage extremes. In the most

critical installations, reliability is enhanced by having redundant hardware and

communications channels, up to the point of having multiple fully equipped control

centres. A failing part can be quickly identified and its functionality automatically

taken over by backup hardware. A failed part can often be replaced without

interrupting the process. The reliability of such systems can be calculated statistically

and is stated as the mean time to failure, which is a variant of Mean Time Between

Failures (MTBF). The calculated mean time to failure of such high reliability systems

can be on the order of centuries.

Communication infrastructure and methods:

a) SCADA systems have traditionally used combinations of radio and direct

wired connections, although SONET/SDH is also frequently used for large

systems such as railways and power stations. The remote management or

monitoring function of a SCADA system is often referred to as telemetry. [2]

Some users want SCADA data to travel over their pre-established corporate

networks or to share the network with other applications. The legacy of the

early low-bandwidth protocols remains, though.

b) SCADA protocols are designed to be very compact. Many are designed to

send information only when the master station polls the RTU. With increasing

security demands (such as North American Electric Reliability Corporation

(NERC) and Critical Infrastructure Protection (CIP) in the US), there is

22

increasing use of satellite-based communication. This has the key advantages

that the infrastructure can be self-contained (not using circuits from the public

telephone system), can have built-in encryption, and can be engineered to the

availability and reliability required by the SCADA system operator. Earlier

experiences using consumer-grade VSAT were poor. Modern carrier-class

systems provide the quality of service required for SCADA. RTUs and other

automatic controller devices were developed before the advent of industry

wide standards for interoperability.

2.3.1 SPECIAL ANALYTICAL REPORT ON SCADA

The United States Army's Training Manual 5-601 covers "SCADA Systems for

C4ISR Facilities". SCADA systems have evolved through 3 generations as follows:

First generation “Monolithic”: In the first generation, computing was done by

mainframe computers. Networks did not exist at the time SCADA was developed.

Thus SCADA systems were independent systems with no connectivity to other

systems. Wide Area Networks were later designed by RTU vendors to communicate

with the RTU. The communication protocols used were often proprietary at that time.

The first-generation SCADA system was redundant since a back-up mainframe

system was connected at the bus level and was used in the event of failure of the

primary mainframe system. Some first generation SCADA systems were developed as

"turn key" operations that ran on minicomputers like the PDP-11 series made by the

Digital Equipment Corporation (DEC). These systems were read only in the sense that

they could display information from the existing analog based control systems to

individual operator workstations but they usually didn't attempt to send control signals

to remote stations due to analog based telemetry issues and control center

management concerns with allowing direct control from computer workstations. They

would also perform alarming and logging functions and calculate hourly and daily

system commodity accounting functions.

Second generation”Distributed”: The processing was distributed across multiple

stations which were connected through a LAN and they shared information in real

time. Each station was responsible for a particular task thus making the size and cost

of each station less than the one used in First Generation. The network protocols used

23

were still mostly proprietary, which led to significant security problems for any

SCADA system that received attention from a hacker. Since the protocols were

proprietary, very few people beyond the developers and hackers knew enough to

determine how secure a SCADA installation was. Since both parties had vested

interests in keeping security issues quiet, the security of a SCADA installation was

often badly overestimated, if it was considered at all.

Third generation"Networked": Due to the usage of standard protocols and the fact

that many networked SCADA systems are accessible from the Internet, the systems

are potentially vulnerable to remote attack. On the other hand, the usage of standard

protocols and security techniques means that standard security improvements are

applicable to the SCADA systems, assuming they receive timely maintenance and

updates.

2.3.2 SECURITY ISSUES

SCADA systems that tie together decentralized facilities such as power, oil, and gas

pipelines and water distribution and wastewater collection systems were designed to

be open, robust, and easily operated and repaired, but not necessarily secure. The

move from proprietary technologies to more standardized and open solutions together

with the increased number of connections between SCADA systems, office networks,

and the Internet has made them more vulnerable to types of network attacks that are

relatively common in computer security. For example, United States Computer

Emergency Readiness Team (US-CERT) released a vulnerability advisory that

allowed unauthenticated users to download sensitive configuration information

including password hashes on an Inductive Automation Ignition system utilizing is a

standard attack type leveraging access to the Tomcat Embedded Web server. Security

researcher Jerry Brown submitted a similar advisory regarding a buffer overflow

vulnerability in a Wonderware In Batch Client ActiveX control. Both vendors made

updates available prior to public vulnerability release. Mitigation recommendations

were standard patching practices and requiring VPN access for secure connectivity.

Consequently, the security of some SCADA-based systems has come into question as

they are seen as potentially vulnerable to cyber attacks.

24

In particular, security researchers are concerned about:

a) The lack of concern about security and authentication in the design,

deployment and operation of some existing SCADA networks the beliefs are

that SCADA systems have the benefit of security through obscurity through

the use of specialized protocols and proprietary interfaces the belief that

SCADA networks are secure because they are physically secured the belief

that SCADA networks are secure because they are disconnected from the

Internet.

b) SCADA systems are used to control and monitor physical processes, examples

of which are transmission of electricity, transportation of gas and oil in

pipelines, water distribution, traffic lights, and other systems used as the basis

of modern society. The security of these SCADA systems is important because

compromise or destruction of these systems would impact multiple areas of

society far removed from the original compromise.

c) For example, a blackout caused by a compromised electrical SCADA system

would cause financial losses to all the customers that received electricity from

that source. How security will affect legacy SCADA and new deployments

remains to be seen.

2.4 INTRODUCTION TO INSTRUMENTATION

Instrumentation is defined as the art and science of measurement and control of

process variables within a production or manufacturing area. Instrument is a device

that measures a physical quantity such as flow, temperature, level, distance, angle, or

pressure. Instruments may be as simple as direct reading thermometers or may be

complex multi-variable process analyzers. Instruments are often part of a control

system in refineries, factories, and vehicles. The control of processes is one of the

main branches of applied instrumentation. Instrumentation can also refer to handheld

devices that measure some desired variable. Diverse handheld instrumentation is

common in laboratories, but can be found in the household as well. For example, a

smoke detector is a common instrument found in most western homes.

Instruments attached to a control system may provide signals used to operate

solenoids, valves, regulators, circuit breakers, or relays. These devices control a

25

desired output variable, and provide either remote or automated control capabilities.

These are often referred to as final control elements when controlled remotely or by a

control system. A Transmitter is a device that produces an output signal, often in the

form of a 4–20 Ma electrical current signal, although many other options using

voltage, frequency, pressure, or Ethernet are possible. This signal can be used for

informational purposes, or it can be sent to a PLC, DCS, SCADA system, Lab View

or other type of computerized controller, where it can be interpreted into readable

values and used to control other devices and processes in the system. Control

instrumentation plays a significant role in both gathering information from the field

and changing the field parameters, and as such are a key part of control loops[1].

2.5 CALIBRATION

Calibration is a comparison between measurements – one of known magnitude or

correctness made or set with one device and another measurement made in as similar

a way as possible with a second device. The device with the known or assigned

correctness is called the standard. The second device is the unit under test, test

instrument, or any of several other names for the device being calibrated.[1].The

formal definition of calibration by the International Bureau of Weights and Measures

is the following: "Operation that, under specified conditions, in a first step, establishes

a relation between the quantity values with measurement uncertainties provided by

measurement standards and corresponding indications with associated measurement

uncertainties (of the calibrated instrument or secondary standard) and, in a second

step, uses this information to establish a relation for obtaining a measurement result

from an indication."

2.5.1 BASIC CALIBRATION PROCESS

The calibration process begins with the design of the measuring instrument that needs

to be calibrated. The design has to be able to "hold a calibration" through its

calibration interval. In other words, the design has to be capable of measurements that

are "within engineering tolerance" when used within the stated environmental

conditions over some reasonable period of time. Having a design with these

characteristics increases the likelihood of the actual measuring instruments

performing as expected. The exact mechanism for assigning tolerance values varies

26

by country and industry type. The measuring equipment manufacturer generally

assigns the measurement tolerance, suggests a calibration interval and specifies the

environmental range of use and storage. The using organization generally assigns the

actual calibration interval, which is dependent on this specific measuring equipment's

likely usage level. A very common interval in the United States for 8–12 hours of use

5 days per week is six months. That same instrument in 24/7 usage would generally

get a shorter interval. The assignment of calibration intervals can be a formal process

based on the results of previous calibrations.

The next step is defining the calibration process. The selection of a standard or

standards is the most visible part of the calibration process. Ideally, the standard has

less than 1/4 of the measurement uncertainty of the device being calibrated. When this

goal is met, the accumulated measurement uncertainty of all of the standards involved

is considered to be insignificant when the final measurement is also made with the 4:1

ratio. The test equipment being calibrated can be just as accurate as the working

standard. If the accuracy ratio is less than 4:1, then the calibration tolerance can be

reduced to compensate. When 1:1 is reached, only an exact match between the

standard and the device being calibrated is a completely correct calibration. Adjusting

the calibration tolerance for the gauge would be a better solution. If the calibration is

performed at 100 units, the 1% standard would actually be anywhere between 99 and

101 units. The acceptable values of calibrations where the test equipment is at the 4:1

ratio would be 96 to 104 units, inclusive. Changing the acceptable range to 97 to 103

units would remove the potential contribution of all of the standards and preserve a

3.3:1 ratio. Continuing, a further change to the acceptable range to 98 to 102 restores

more than a 4:1 final ratio. This is a simplified example. The mathematics of the

example can be challenged. It is important that whatever thinking guided this process

in an actual calibration be recorded and accessible. Informality contributes to

tolerance stacks and other difficult to diagnose post calibration problems. Also in the

example above, ideally the calibration value of 100 units would be the best point in

the gage's range to perform a single-point calibration. It may be the manufacturer's

recommendation or it may be the way similar devices are already being calibrated.

Multiple point calibrations are also used. Depending on the device, a zero unit state,

the absence of the phenomenon being measured, may also be a calibration point. Or

zero may be resettable by the user-there are several variations possible. Again, the

27

points to use during calibration should be recorded. There may be specific connection

techniques between the standard and the device being calibrated that may influence

the calibration. For example, in electronic calibrations involving analog phenomena,

the impedance of the cable connections can directly influence the result. All of the

information above is collected in a calibration procedure, which is a specific test

method.

These procedures capture all of the steps needed to perform a successful calibration.

The manufacturer may provide one or the organization may prepare one that also

captures all of the organization's other requirements. There are clearinghouses for

calibration procedures such as the Government-Industry Data Exchange Program

(GIDEP) in the United States. This exact process is repeated for each of the standards

used until transfer standards, certified reference material sand or natural physical

constants, the measurement standards with the least uncertainty in the laboratory, are

reached. [1]This establishes the traceability of the calibration. See Metrology for other

factors that are considered during calibration process development. After all of this,

individual instruments of the specific type discussed above can finally be calibrated.

The process generally begins with a basic damage check. Some organizations such as

nuclear power plants collect "as-found" calibration data before any routine

maintenance is performed. After routine maintenance and deficiencies detected during

calibration are addressed, an "as-left" calibration is performed. More commonly, a

calibration technician is entrusted with the entire process and signs the calibration

certificate, which documents the completion of a successful calibration.

2.5.2 INSTRUMENT CALIBRATION

Calibration may be called for reasons below:

a) A new instrument.

b) After an instrument has been repaired or modified.

c) When a specified time period has elapsed.

d) When a specified usage (operating hours) has elapsed, before and/or after a

critical measurement.

e) After an event, for example. after an instrument has had a shock, vibration, or

has been exposed to an adverse condition which potentially may have put it

28

out of calibration or damage it.

f) Sudden changes in weather. Whenever observations appear questionable or

instrument indications do not match the output of surrogate instruments.

g) As specified by a requirement, e.g., customer specification, instrument

manufacturer recommendation. In general use, calibration is often regarded as

including the process of adjusting the output or indication on a measurement

instrument to agree with value of the applied standard, within a specified

accuracy. For example, a thermometer could be calibrated so the error of

indication or the correction is determined, and adjusted (e.g. via calibration

constants) so that it shows the true temperature in Celsius at specific points on

the scale.

h) This is the perception of the instrument's end-user. However, very few

instruments can be adjusted to exactly match the standards they are compared

to. For the vast majority of calibrations, the calibration process is actually the

comparison of an unknown to a known and recording.

2.6 RTD ( RESISTANCE TEMPRATURE DETECTOR)

Resistance thermometers, also called resistance temperature detectors ('RTD's), are

sensors used to measure temperature by correlating the resistance of the RTD element

with temperature. Most RTD elements consist of a length of fine coiled wire wrapped

around a ceramic or glass core. The element is usually quite fragile, so it is often

placed inside a sheathed probe to protect it. The RTD element is made from a pure

material, typically platinum, nickel or copper. The material has a predictable change

in resistance as the temperature changes; it is this predictable change that is used to

determine temperature.[1] They are slowly replacing the use of thermocouples in

many industrial applications below 600 °C, due to higher accuracy and repeatability.

2.6.1 CALIBRATION

To characterize the R v/s T relationship of any RTD over a temperature range that

represents the planned range of use, calibration must be performed at temperatures

other than 0°C and 100°C. Two common calibration methods are the fixed point

29

method and the comparison method. Fixed point calibration, used for the highest

accuracy calibrations, uses the triple point, freezing point or melting point of pure

substances such as water, zinc, tin, and argon to generate a known and repeatable

temperature. Fixed point calibrations provide extremely accurate calibrations

(within±0.001°C). A common fixed point calibration method for industrial-grade

probes is the ice bath. The equipment is inexpensive, easy to use, and can

accommodate several sensors at once. The ice point is designated as a secondary

standard because its accuracy is ±0.005°C (±0.009°F), compared to ±0.001°C

(±0.0018°F) for primary fixed points. Comparison calibrations, commonly used with

industrial RTDs, the thermometers being calibrated are compared to calibrated

thermometers by means of a bath whose temperature is uniformly stable. Unlike fixed

point calibrations, comparisons can be made at any temperature between –100°C and

500°C (–148°F to 932°F). This method might be more cost-effective since several

sensors can be calibrated simultaneously with automated equipment. These

electrically heated and well-stirred baths use silicone oils and molten salts as the

medium for the various calibration temperatures.

2.6.2 ELEMENT TYPES

There are three main categories of RTD sensors:-

a) Thin Film

b) Wire-Wound

c) Coiled Elements

While these types are the ones most widely used in industry there are some places

where other more exotic shapes are used, for example carbon resistors are used at

ultra low temperatures (-173 °C to -273°C). Carbon resistor elements are widely

available and are very inexpensive. They have very reproducible results at low

temperatures. They are the most reliable form at extremely low temperatures. They

generally do not suffer from significant strain gauge effects. Strain free elements use a

wire coil minimally supported within a sealed housing filled with an inert gas. They

consisted of platinum wire loosely coiled over a support structure so the element is

free to expand and contract with temperature, but it is very susceptible to shock and

vibration as the loops of platinum can sway back and forth causing deformation. Thin

film elements have a sensing element that is formed by depositing a very thin layer of

30

resistive material, normally platinum, on a ceramic substrate. This layer is usually just

10 to 100 angstroms (1 to 10 nanometers) thick. This film is then coated with an

epoxy or glass that helps protect the deposited film and also acts as a strain relief for

the external lead-wires. [1]. Disadvantages of this type are that they are not as stable

as their wire wound or coiled counterparts. They also can only be used over a limited

temperature range due to the different expansion rates of the substrate and resistive

deposited giving a "strain gauge" effect that can be seen in the resistive temperature

coefficient. These elements work with temperatures to 300 °C without further

packaging but can operate up to 500 °C when suitably encapsulated in glass or

ceramic. Wire-wound elements can have greater accuracy, especially for wide

temperature ranges. The coil diameter provides a compromise between mechanical

stability and allowing expansion of the wire to minimize strain and consequential

drift. The sensing wire is wrapped around an insulating mandrel or core. The winding

core can be round or flat, but must be an electrical insulator. The coefficient of

thermal expansion of the winding core material is matched to the sensing wire to

minimize any mechanical strain. This strain on the element wire will result in a

thermal measurement error. The sensing wire is connected to a larger wire, usually

referred to as the element lead or wire. This wire is selected to be compatible with the

sensing wire so that the combination does not generate an emf that would distort the

thermal measurement. These elements work with temperatures to 660C. Coiled

elements have largely replaced wire-wound elements in industry. This design has a

wire coil which can expand freely over temperature, held in place by some

mechanical support which lets the coil keep its shape. This “strain free” design allows

the sensing wire to expand and contract free of influence from other materials. The

basis of the sensing element is a small coil of platinum sensing wire. This coil

resembles a filament in an incandescent light bulb. The housing or mandrel is a hard

fired ceramic oxide tube with equally spaced bores that run transverse to the axes. The

coil is inserted in the bores of the mandrel and then packed with a very finely ground

ceramic powder. This permits the sensing wire to move while still remaining in good

thermal contact with the process. These Elements works with temperatures to 850 °C.

The current international standard which specifies tolerance and the temperature-to-

electrical resistance relationship for platinum resistance thermometers is IEC

60751:2008, ASTM E1137 is also used in the United States. By far the most common

devices used in industry have a nominal resistance of 100ohmsat 0 °C, and are called

31

Pt100 sensors ('Pt' is the symbol for platinum, 100 for the resistance in ohm at 0°C).

The sensitivity of a standard 100 ohm sensor is a nominal 0.385 ohm/°C. RTDs with a

sensitivity of 0.375 and 0.392 ohm/°C as well as a variety of others are also available.

2.7 THERMOCOUPLE

A thermocouple consists of two dissimilar conductors in contact which produce a

voltage when heated. The voltage produced is dependent on the difference of

temperature of the junction to other parts of the circuit. Thermocouples are a widely

used type of temperature sensor for measurement and control and can also be used to

convert a temperature gradient into electricity. Commercial thermocouples are

inexpensive, interchangeable, are supplied with standard connectors, and can measure

a wide range of temperatures.

32

Fig 2.6 Thermocouple

In contrast to most other methods of temperature measurement, thermocouples are

self-powered and require no external form of excitation. The main limitation with

thermocouples is accuracy; system errors of less than one degree Celsius (°C) can be

difficult to achieve. Any junction of dissimilar metals will produce an electric

potential related to temperature. Thermocouples for practical measurement of

temperature are junctions of specifically which have a predictable and repeatable

relationship between temperature and voltage. Different alloys are used for different

temperature ranges. Properties such as resistance to corrosion may also be important

when choosing a type of thermocouple. Where the measurement point is far from the

measuring instrument, the intermediate connection can be made by extension wires

which are less costly than the materials used to make the sensor. Thermocouples are

usually standardized against a reference temperature of 0 degrees Celsius; practical

instruments use electronic methods of cold-junction compensation to adjust for

varying temperature at the instrument terminals. Electronic instruments can also

compensate for the varying characteristics of the thermocouple, and so improve the

precision and accuracy of measurements. Thermocouples are widely used in science

and industry; applications include temperature measurement gas turbine exhaust,

diesel engines, and other industrial processes.

33

CHAPTER-3

RESULTS

During calibration following results are obtained with K-type thermocouple which

are tabulated in table no 3.1

TABLE 3.1

Millivolts (source) Temperature(deg.C)

00.00 29

00.40 39

00.80 59

1.00 54

1.20 59

The calibration of resistance temperature detector is done and following results are

obtained which are tabulated in table 3.2

TABLE 3.2

34

Temperature(deg.C) Resistance(ohms)

25 100

35 103.9

45 107.79

50 109.73

55 111.67

These values in observation are calculated as per calibration chart standards of

industrial instruments. In this same manner values of RTD is also measured, vaccum

gauge was also analysed with different values of weight applied. In automation

techniques study of various factors in PLC and SCADA and their work with industrial

machines are analysed, for the combination of automation and instrumentation.

CHAPTER-4

CONCLUSION

During the training period in instrumentation section, calibration was done as per the

industrial calibration standards and was properly checked and verified. PLC and

SCADA automation techniques and programming was studied, as per the industrial

requirements. Rockwell automation techniques and new discoveries of SCADA

system featuring 3D graphics were analyzed , temperature, pressure variations and

flow controls are analyzed through SCADA, with proper Human Machine Interface.

Overall this training period will be fruitful for the future career start.

35

REFERENCES

[1] A.K. Sawhney – Electronics measurements and insturuments ( second edition)

vol. 1213

[2] David bailey and Edwin wright – SCADA basics, second edition( 2003)

[3] W.BOLTON – Programable logic controllers, fourth edition (2006) vol. 229

Links

1) https://www.rockwellautomation.com/rockwellautomation/industries/

automotive

2) http://literature.rockwellautomation.com/idc/groups/literature/documents/

ar/journk-ar010_-en-p.pdf

3) http://www.idc-online.com/technical_references/pdfs/

electrical_engineering/Control_of_Boiler_Operation_using_PLC%20-

%20SCADA.pdf

36