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ABOUT NTPC

Indias largest power company, NTPC was set up in 1975 to acceleratepower development in India. NTPC is emerging as a diversified powermajor with presence in the entire value chain of the power generation

business. Apart from power generation, which is the mainstay of thecompany, NTPC has already ventured into consultancy, power trading,

ash utilization and coal mining. NTPC ranked 341st in the 2010 Forbes

Global 2000 ranking of the Worlds biggest companies. NTPC became a

Maharatna company in May 2010 one of the only four power training.The total installed capacity of the company is 39,174 MW (including JVs)

with 16 coal based and 7 gas based stations, located across the country. Inaddition under JVs, 7 stations are coal based & another station uses

naphtha/LNG as fuel. The company has set a target to have an installedpower generating capacity of 1,28,000 MW by the year 2032.

The capacity will have a diversified fuel mix comprising 56% coal, 16%Gas, 11% Nuclear and 17% Renewable Energy Sources(RES) includinghydro. By 2032, non-fossil fuel based generation capacity shall make up

nearly 28% of NTPCs portfolio.

NTPC has been operating its plants at high efficiency levels.

Although the company has 17.75% of the total national capacity,it contributes 27.40% of total power generation due to its focus

on high efficiency.

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In October 2004, NTPC launched its Initial Public Offering (IPO) consisting of5.25% as fresh issue and 5.25% as offer for sale by Government of India. NTPC

thus became a listed company in November 2004 with the Government holding89.5% of the equity share capital. In February 2010, the Shareholding of

Government of India was reduced from 89.5% to 84.5% through Further Public

Offer. The rest is held by Institutional Investors and the Public.

Strategies of NTPC

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TechnologicalInitiatives

Introduction of steam generators (boilers) of the size of 800 MW.

Integrated Gasification Combined Cycle (IGCC) Technology.

Launch of Energy Technology Centre -A new initiative for development

of technologies with focus on fundamental R&D.

The Company sets aside up to 0.5% of the profits for R&D.

Roadmap developed for adopting Clean Development.

Mechanism to help get / earn Certified Emission Reduction.

Corporate Social Responsibility

As a responsible corporate citizen NTPC has taken up number of CSR initiatives.

NTPC Foundation formed to address Social issues at national level

NTPC has framed Corporate Social Responsibility Guidelines committing up

To 0.5% of net profit annually for Community Welfare.

The welfare of project affected persons and the local population around

NTPC projects are taken care of through well drawn Rehabilitation and

Resettlement policies.

Thecompanyhasalso takenupdistributed generation for remote ruralareas

Partnering government in various initiatives

Consultant role to modernize and improvise several plants across the country.

Disseminate technologies to other players in the sector.

Consultant role Partnership in Excellence Programme for improvement of

PLF of 15 Power Stations of SEBs.

Rural Electrification work under Rajiv Gandhi Garmin Vidyutikaran.

Environment management

AllstationsofNTPC are ISO14001certified

Various groups to care of environmental issues

The Environment Management Group.

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Ash utilization Division

. Afforestation Group.

Centre for Power Efficiency & Environment Protection.

Group on Clean Development Mechanism.

NTPC is the second largest owner of trees in the country after the Forest

department

VisionTo be the worlds largest and best power producer, powering Indias growth.

Mission

Develop and provide reliable power, related products and services at competitive

prices, integrating multiple energy sources with innovative and eco-friendly

technologies and contribute to society.

CoreValuesBECOMMITTEDB Business Ethics

E Environmentally & Economically Sustainable

C Customer Focus

O Organizational & Professional Pride

M Mutual Respect & Trust

M Motivating Self & others

I Innovation & Speed

T Total Quality for Excellence

T Transparent & Respected Organization

E Enterprising

D Devoted

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JOURNEYOFNTPC

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NTPCEnvironment Policy

NTPC is committed to the environment, generating power at minimal environmental cost

and preserving the ecology in the vicinity of the plants. NTPC has undertaken massive a

forestation in the vicinity of its plants. Plantations have increased forest area and reduced

barren land. The massive a forestation by NTPC in and around its Ramagundam Power

station (2600 MW) have contributed reducing the temperature in the areas by about 3c.

NTPC has also taken proactive steps for ash utilization. In 1991, it set up Ash Utilization

Division A

"Centre forPower Efficiency and Environ ment Protection- CENPEE" has been

established in NTPC with the assistance of United States Agency for International

Development- USAID. CENPEEP is efficiency oriented, eco-friendly and eco-nurturing

initiative - a symbol of NTPC's concern towards environmental protection and continued

commitment to sustainable power development in India. As a responsible corporate

citizen, NTPC is making constant efforts to improve the socio-economic status of

the people affected by its projects. Through its Rehabilitation and Resettlement

programmes, the company endeavors to improve the overall socio economic status

Project Affected Persons. NTPC was among the first Public Sector Enterprises to enter

into a Memorandum of Understanding-MO U with the Government in 1987-88. NTPC

has been placed under the 'Excellent category' (the best category) every year since the

MOU system became operative. Harmony between man and environment is the essence

of healthy life and growth. Therefore, maintenance of ecologica l balance and a pristine

environment has been of utmost importance to NTPC. It has been taking

various measures discussed below for mitigation of environment pollution due to power

generation.

NTPCis the secondlargestowneroftrees in the countryafter the Forest department.

As early as in November 1995, NTPC brought out a comprehensive document entitled

"NTPC Environment Policy and Environment Management System". Amongst the

guiding principles adopted in the document is companys proactive approach to

environment, optimum utilization of equipment, adoption of latest technologies and

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continual environment improvement. The policy also envisages efficient utilization of

resources, thereby minimizing waste, maximizing ash utilization and providing green belt

all around the plant for maintaining ecological balance.

Environment Management, Occupational Health and Safety Systems:

NTPC has actively gone for adoption of best international practices on environment,

occupational health and safety areas. The organization has pursued the Environmental

Management System (EMS) ISO 14001 and the Occupational Health and Safety

Assessment System OHSAS 18001 at its different establishments. As a result of pursuing

these practices, all NTPC power stations have been certified for ISO 14001 & OHSAS

18001 by reputed national and international Certifying Agencies.

Pollution Control systems:

While deciding the appropriate technology for its projects, NTPC integrates many

environmental provisions into the plant design. In order to ensure that NTPC complies

with all the stipulated environment norms, various state-of-the-art pollution control

systems / devices as discussed below have been installed to control air and water

pollution.

Electrostatic Precipitators:

The ash left behind after combustion of coal is arrested in high efficiency Electrostatic

Precipitators (ESPs) and particulate emission is controlled well within the stipulated

norms. The ash collected in the ESPs is disposed to Ash Ponds in slurry form.

Cooling Towers:

Cooling Towers have been provided for cooling the hot Condenser cooling water in

closed cycle, Condenser Cooling Water (CCW) Systems. This helps in reduction in

thermal pollution and conservation of fresh water.

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AshDykes&AshDisposalsystems:Ash ponds have been provided at all coal based stations except Dadri where Dry Ash

Disposa l System has been provided. Ash Ponds have been divided into lagoons and

provided with garlanding arrangement for changeover of the ash slurry feed points for

even filling of the pond and for effective settlement of the ash particles.

Ash in slurry form is discharged into the lagoons where ash particles get settled from the

slurry and clear effluent water is discharged from the ash pond. The discharged effluents

conform to standards specified by CPCB and the same is regularly monitored.

At its Dadri Power Station, NTPC has set up a unique system for dry ash collection and

disposal facility with Ash Mound formation. This has been envisaged for the first time in

Asia which has resulted in progressive development of green belt besides far less

requirement of land and less water requirement as compared to the wet ash disposal

system.

AshWater Recycling System:

Further, in a number of NTPC stations, as a proactive measure, Ash Water Recycling

System (AWRS) has been provided. In the AWRS, the effluent from ash pond is

circulated back to the station for further ash sluicing to the ash pond. This helps in

savings of fresh water requirements for transportation of ash from the plant.

The ash water recycling system has already been installed and is in operation atRamagundam, Simhadri, Rihand, Talcher Kaniha, Talcher Thermal, Kahalgaon, Korba

and Vindhyachal. The scheme has helped stations to save huge quantity of fresh water

required as make-up water for disposal of ash.

DryAshExtraction System(DAES):

Dry ash has much higher utilization potential in ash-based products (such as bricks,

aerated autoclaved concrete blocks, concrete, Portland pozzolana cement, etc.). DAES

has been installed at Unchahar, Dadri, Simhadri, Ramagundam, Singrauli, Kahalgaon,

Farakka, Talcher Thermal, Korba, Vindhyachal, Talcher Kaniha and BTPS.

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ABOUTBTPS

BADARPUR THERMAL POWER STATION was established on 1973 and it was the

part of Central Government. On 01/04/1978 is was given as No Loss No Profit Plant ofNTPC. Since then operating performance of NTPC has been considerably above the

national average. The availability factor for coal stations has increased from 85.03 % in

1997-98 to 90.09 % in 2006-07, which compares favorably with international standards.

The PLF has increased from 75.2% in1997-98 to 89.4% during the year 2006-07 which is

the highest since the inception of NTPC.

Badarpur thermal power station started with a single 95 mw unit. There were 2moreunits

(95MWeach) installed innext2 consecutive years.Now it hastotal five units withtotalcapacityof

720 MW.OwnershipofBTPS was transferred toNTPC with effect from 01.06.2006 through

GOIs Gazette Notification .

The power is supplied to a 220 KV network that is a part of the northern grid. The ten

circuits through which the power is evacuated from the plant are:

1. Mehrauli

2. Okhla

3. Ballabgarh

4. Indraprastha

5. UP (Noida)

6. Jaipur

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Givenbelow arethedetailsofunit with theyear theyre installed.

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OPERATION OFAPOWERPLANT

BasicPrincipleAs per FARADAYs Law-Whenever the amount of magnetic flux linked with a circuit

changes, an EMF is produced in the circuit. Generator works on the principle of

producing electricity. To change the flux in the generator turbine is moved in a great

speed with steam. To produce steam, water is heated in the boilers by burning the coal.

In a Badarpur Thermal PowerStation, steam is produced and used to spin a turbine that

operates a generator. Water is heated, turns into steam and spins a steam turbine which

drives an electrical generator. After it passes through the turbine, the steam is condensed

in a condenser; this is known as a Rankine cycle.

The electricity generated at the plant is sent to consumers through high-volta ge power

lines The Badarpur Thermal Power Plant has Steam Turbine-Driven Generators which

has a collective capacity of 705MW. The fuel being used is Coal which is supplied from

the Jharia Coal Field in Jharkhand. Water supply is given from the Agra Canal.

BasicStepsofElectricity GenerationThebasic steps in the generation of electricity fromcoal involves followingsteps:

Coal to steam

Steam to mechanical power

Mechanical power to electrical power

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Coal to electricity basics

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PARTSOFAPOWERPLANT

Thevarious parts are listedbelow:-

1. Cooling tower

2. Cooling water pump

3. Transmission line (3-phase)

4. Unit transformer (3-phase)

5. Electric generator (3-phase)

6. Low pressure turbine

7. Condensate extraction pump

8. Condenser

9. Intermediate pressure turbine

10. Steam governor valve

11. High pressure turbine

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12. Deaerator

13. Feed heater

14. Coal conveyor

15. Coal hopper

16. Pulverised fuel mill17. Boiler drum

18. Ash hopper

19. Super heater

20. Forced draught fan

21. Reheater

22. Air intake

23. Economiser

24. Air preheater

25. Precipitator

26. Induced draught fan

27. Flue Gas

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This division is basically brain of the power plant and this division is responsible for:

1. For controlling the entire process of boiler, turbine n generator.

2. Is responsible for protection of boiler turbine & generator & associated auxiliaries.

3. It is responsible for display of all the parameters to the operator for taking the manual

action in case of emergency.

4. Responsible for logging of sequence of events taking place in the control room

Figure 1: CONTROL UNIT

This department is the brain of the plant because from the relays to transmitters followed by the

electronic computation chipsets and recorders and lastly the controlling circuitry, all fall under this.

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This division also calibrates various instruments and takes care of any faults occurring in any of the

auxiliaries in the plant provided for all the equipments . Tripping can be considered as the series of

instructions connected through OR GATE. When the main equipments of this laboratories are

relay and circuit breakers.

GENESIS OF THE PROJECT:

There are very transient conditions during the light up of the boiler. At this point, the level in the

drum fluctuates heavily & frequently. So, if the drum level works on properly on auto loop, then it

will be huge relief to operator and it may even save the unit from tripping on drum level

protection. That is why this project is chosen.

OBJECTIVE:

The objective of the boiler drum level control strategy is to maintain the water/steam interface at

its optimum level to provide a continuous mass/heat balance by replacing every pound of steam

leaving the boiler with a pound of feed water to replace it. As mentioned above if the level is above

+175mm then the turbine may get damaged or if the level is below -175mm then the boiler

happens to starvation. The objective of the entire project is to design the controlling element for

the control of valve of drum which can be designed manually and automatically both. The

controlling element will control the opening and closing of valve of drum according to error signal

generated by I-06R mini card. To serve this purpose the following steps are to be taken

The following are the main objectives of the project:

1) Understanding the input measurement techniques.

2) Understanding the control logic and hence designing it.

3)

Understanding and simulating the controlling element i.e. valve actuator.

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C&ILABS

Control and Instrumentation Department has following labs:

Manometry Lab.

Protection and Interlock s Lab.

Automation Lab.

Electronics Lab.

Water Treatment Plant.

Furnaces Safety Supervisory System Lab

OPERATION ANDMAINTAINANCE

Control and Instrumentation Department has following Control Units:1. Unit Control Board

2. Main Control Board

3. Analog & Digital Signal Control

4. Current Signal Control

This department is thebrain of the plant because from the relaysto transmittersfoll owed bythe

electronic computation chipsets and recordersand lastly thecontroll ing circuitry, all fall under thi s.

A View of Control Room at BTPS

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1. MANOMETRY LAB

TRANSMITTERS

It is used for pressure measurements of gases and liquids, its working principle is that the

input pressure is converted into electrostatic capacitance and from there it is conditionedand amplified. It gives an output of 4-20 ma DC. It can be mounted on a pipe or a wall.

For liquid or steam measurement transmitte rs is mounted below main process piping andfor gas measurement transmitter is placed above pipe.

MANOMETER

Its a tube which is bent, in U shape. It is filled with a liquid. This device corresponds to a

difference in pressure across the two limbs.

BOURDEN PRESSURE GAUGE

Its an oval section tube. Its one end is fixed. It is provided with a pointer to indicate the

pressure on a calibrated scale. It is of 2 types :

(a) Spiral type: for Low pressure measurement.

(b) Helical Type: for High pressure measurement. While selecting Pressure Gauge these

parameters should keep in mind-

1. Accuracy

2. Safety

3. Utility

4. Price

ACCURACY

Higher Accuracy implies Larger Dial Size for accuracy of small and readable pressure

scale increments.

SAFETY

While selecting Pressure Gauge it should consider that Gauge Construction Materialshould be chemically compatible with the environment either inside or outside it.

UTILITY

It should keep it mind that range of the Gauge should be according to our need elseOverpressure Failure may occur resulting in damage of Gauge.

PRICE

Lager the Gauges Dial size larger would be our price. Better Gauges Construction

material also increases the cost. So they must be chosen according to our need.

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2. PROTECTION ANDINTERLOCKING

INTERLOCKING

It is basically interconnecting two or more equipments so that if one equipment fails otherone can perform the tasks. This type of interdependence is also created so

that equipments connected together are started and shut down in the specific sequence to

avoid damage. For protection of equipments tripping are provided for all the equipments.Tripping can be considered as the series of instructions connected through OR GATE,which trips the circuit. The main equipments of this lab are relay and circuit breakers.

Some of the instrument uses for protection are:

RELAY

Relay is a sensing device that makes your circuit ON or OFF. They detect the

abnormal conditions in theelectrical circuits bycontinuouslymeasuring theelectricalquantities,whicharedifferent under normaland faultyconditions, like current, voltage frequency. Havingdetectedthe fault the relay operates tocomplete the trip circuit, whichresults in theopening of

the circuit breakers and disconnect the faulty circuit.

There are different types of relays:

i. Current relay

ii. Potential relay

iii. Electromagnetic relay

iv. Numerical relay etc.

FUSES

It is a short piece of metal inserted in the circuit, which melts when heavy current flowsthrough

it and thus breaks the circuit.

Usually silver is used as a fuse material because:

a. The coefficient of expansion of silver is very small. As a result no criticalfatigue occurs and thus the continuous full capacity normal current ratings areassured for the long time.

b. The conductivity of the silver is unimpaired by the surges of the current thatproduces temperatures just near the melting point

c. Silver fusible elements can be raised from normal operating temperature tovaporization quicker than any other material because of its comparatively low

specific heat.

Miniature Circuit Breaker

They are used with combination of the control circuits to.

a) Enable the staring of plant and distributors.

b) Protect the circuit in case of a fault. In consists of current carrying contacts, one

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There are three types of trips.

I.

MANUAL TRIP

II.

THERMAL TRIP

III.

SHORT CIRCUIT TRIP

Protection and Interlock System-

1) HIGH TENSION CONTROL CIRCUIT for high tension system the control

system is excited by separate D.C supply. For starting the circuit conditionsshould be in series with the starting coil of the equipment to energize it. Becauseif even a single condition is not true then system will not start.

2) LOW TENSION CONTROL CIRCUIT For low tension system the controlcircuits are directly excited from the 0.415 KV A.C supply.

The same circuit achieves both excitation and tripping. Hence the tripping coil isprovided for emergency tripping if the interconnection fails.

3.AUTOMATION LAB

This lab deals in automating the existing equipment and feeding routes. Earlier, the oldtechnology dealt with only (DAS) Data Acquisition System and came to be knownas primary systems. The modern technology or the secondary systems are coupled with

(MIS) Management Information System. But this lab universally applies the pressuremeasuring instruments as the controlling force. However, the relays are also provided

but they are used only for protection and interlocks.

4. PYROMETRY LAB

LIQUID IN GLASS THERMOMETER

Mercury in the glass thermometer boils at 340 C which limits the range of temperaturethat can be measured. It is L shaped thermometer which is designed to reach all

inaccessible places.

ULTRA VIOLET CENSOR-This device is used in furnace and it measures the intensity of ultra violet rays there andaccording to the wave generated which directly indicates the temperature in the furnace.

THERMOCOUPLES

This device is based on SEEBACK and PELTIER effect. It comprises of two junctions at

different temperature. Then the emf is induced in the circuit due to the flow of electrons.This is an important part in the plant.

RTD (RESISTANCE TEMPERATURE DETECTOR)It performs the function of thermocouple basically but the difference is of a resistance. In

thi d t th h i th i t th t t diff i d I thi

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.5. FURNACE SAFETY ANDSUPERVISORY SYSTEM LAB

This lab has the responsibility of starting fire in the furnace to enable the burning of coal.For first stage coal burners are in the front and rear of the furnace and for the second and

third stage corner firing is employed. Unburnt coal is removed using forced draft orinduced draft fan. The temperature inside the boiler is 1100C and its heights 18 to 40 m.

It is made up of mild steel. An ultra violet sensor is employed in furnace to measure theintensity of ultra violet rays inside the furnace and according to it a signal in the sameorder of same mV is generated which directly indicates the temperature of the furnace.

For firing the furnace a 10 KV spark plug is operated for ten seconds over a sprayof diesel fuel and pre-heater air along each of the feeder-mills. The furnace has six feeder

mills each separated by warm air pipes fed from forced draft fans. In first stage indirectfiring is employed that is feeder mills are not fed directly from coal but are fed from three

feeders but are fed from pulverized coalbunkers. The furnace can operate on theminimum feed from three feeders but under no circumstances should anyone be leftout under operation, to Prevent creation of pressure different with in the furnace, which

threatens to blast it.

6. ELECTRONICS LAB

This lab undertakes the calibration and testing of various cards. It houses various types of

analytica l instruments like oscilloscopes, integrated circuits, cards auto analyzers etc.

Various processes undertaken in this lab are:1. Transmitter converts mV to mA.

2. Auto analyzer purifies the sample before it is sent to electrodes. It extracts the

magnetic portion.

ANNUNCIATIN CARDS

They are used to keep any parameter like temperature etc. within limits. It gets a signalif parameter goes beyond limit. It has a switching transistor connected to relay that helps

in alerting the UCB.

CONTROL &MONITORING MECHANISMS

There are basically two types of Problems faced in a Power Plant

1. Metallurgical

2. Mechanical

Mechanical Problem can be related to Turbines that is the max speed permissible for aturbine is3000 rpm so speed should be monitored and maintained at that level.

Metallurgica l Problem can be view as the max Inlet Temperature for Turbine is 1060C so temperature should be below the limit. Monitoring of all the parameters is necessaryfor the safety of both:

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So the Parameters to be monitored are:

1.Speed2.Temperature

3.Current4.Voltage 5.Pressure

6.Eccentricity7.Flow ofGases

8.Vacuum Pressure 9.Valves10.Level

11.Vibration

PRESSURE MONITORING

Pressure can be monitored by three types of basic mechanisms

1. Switches

2. Gauges

3. Transmitter type

For gauges we use Bourdon tubes. The Bourdon Tube is a non-liquid pressuremeasurement device. It is widely used in applications where inexpensive static pressure

measurements are needed. A typical Bourdon tube contains a curved tube that is opento external pressure input on one end and is coupled mechanically to an indicating needle

on the other end, as shows schematically below.

Typical Bourdon Tube Pressure Gages

For Switches pressure switches are used and they can be used for digita l means ofmonitoring as switch being ON is referred as high and being OFF is as low.

All the monitored data is converted to either Current or Voltage parameter.

The Plant standard for current and voltage are as under

V lt 0 10 V lt

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We use 4mA as the lower value so as to check for disturbances and wire breaks.

Accuracy of such systems is very high.

ACCURACY: 0.1%

Programmable Logic Circuits (PLCs) are used in the process as they are the heartof Instrumentation.

TEMPERATURE MONITORING

We can use Thermocouples or RTDs for temperature monitoring. Normally RTDs are

used for low temperatures.

Thermocouple selection depends upon two factors:

1. Temperature Range

2. Accuracy Required

Normally used Thermocouple is K Type Thermocouple:

In this we use Chromel (Nickel-Chromium Alloy) / Alumel (Nickel-Alumin ium Alloy) astwo metals. This is the most commonly used general purpose thermocouple. It is

inexpensive and, owing to its popularity, available in a wide variety of probes. They are

available in the200C to +1200C range. Sensitivity is approximately 41 V/C.

RTDs are also used but not in protection systems due to vibrational errors.

We pass a constant current through the RTD. So that if R changes then the Voltage also

changes

RTDs used in Industries are Pt100 And Pt1000

Pt100: 0C100 ( 1 = 2.5 0C )

Pt1000: 0C - 1000

Pt1000 is used for higher accuracy.

The gauges used for Temperature measurements are mercury filled Temperature gauges.

For Analog medium thermocouples are used and for Digital medium Switches are used

which are basically mercury switches.

FLOWMEASUREMENT

Flow measurement does not signify much and is measured just for metering purposes and

for monitoring the processes

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occasionally misspelled as 'Rotometer'.

It belongs to a class of meters called variable area meters, which measure flow ra te

by allowing the cross sectional area the fluid travels through to vary, causing some

measurable effect. A rotameter consists of a tapered tube, typically made of glass, with a

float inside that is pushed up by flow and pulled down by gravity. At a higher flow ratemore area (between the float and the tube) is needed to accommodate the flow, so the

float rises. Floats are made in many different shapes, with spheres and spherical ellipses

being the most common. The float is shaped so that it rotates axially as the fluid passes.

This allows you to tell if the float is stuck since it will only rotate if it is not.

For Digital measurements Flap system is used.

For Analog measurements we can use the following methods :

1. Flow meters

2. Venturimeters /Orifice meters

3. Turbines

4. Mass flow meters (oil level)

5. Ultrasonic Flow meters

6. Magnetic Flow meter (water level )

Selection of flow meter depends upon the purpose, accuracy and liquid to be measured so

different types of meters used.

TURBINE TYPE:

They are simplest of all. They work on the principle that on each rotation of the turbine a

pulse is generated and that pulse is counted to get the flow rate.

VENTURIMETERS :

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fluids (such as the approximation of a water jet), and the theoretical pressure drop at the

constriction would be given by (/2)(v22- v12).

And we know that rate of flow is given by:

Flow= k (D.P)

Where DP is Differential Pressure or the Pressure Drop.

CONTROL VALVES

A valve is a device that regulates the flowofsubstances (either gases, fluidized solids,

slurries, or liquids) by opening, closing, or partially obstructing various passageways.

Valves are technically pipe fittings, but usually are discussed separately. Valves are

used in a variety of applications including industria l, military, commercial, residential,

transportation. Plumbing valves are the most obvious in everyday life, but many more areused.

Some valves are driven by pressure only, they are mainly used for safety purposes in

steam engines and domestic heating or cooking appliances . Others are used in

a controlled way, like in Otto cycle engines driven by a camshaft, where they play a

major role in engine cycle control.

Many valves are controlled manually with a handle attached to the valve stem. If thehandle is turned a quarter of a full turn (90) between operating positions, the valve

is called a quarter-turn valve. Butterfly valves, ball valves, and plug valves are often

quarter-turn valves. Valves can also be controlled by devices called actuators attached to

the stem. They can be electromechanical actuators such as an electric motor or solenoid,

pneumatic actuators which are controlled by air pressure, or hydraulic actuators which

are controlled by the pressure of a liquid such as oil or water. So there are basically three

types of valves that are used in power industries besides the handle valves.

They are :

PNEUMATIC VALVES They are air or gas controlled which is compressed to turn or

move them

HYDRAULIC VALVES They utilize oil in place of Air as oil has better compression

MOTORISED VALVES These valves are controlled by electric motors

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Boiler Feed Pump

High Pressure

Heater &

Economizer

Drum Down Comer

Bottom Ring

Header

Through Water

Walls It Goes UpFurnace

Steam + Water

Drum

(Steam + Water)

Water Valves

Fire

The entire functioning of any auto loop may be primarily being divided in to four parts.

1) Measurement of Input : This is the first step towards designing the auto controller. In this

project, we will study the various measurement techniques of the drum level. Primarily we will focus

on the two techniques as-

i) Drum level measurementtechnique by differential pressure measurement: In this variable head is

compared with constant head and thus giving the variable electrical signal in terms of the 4 to 20 ma.

This DP signal is corrected for the density by measuring the drum pressure and temperature of the

saturated steam.

ii) Hydra step measurement: This method is based on the principle of the resistivity difference of the

steam & water. This method gives the discrete signal hence cannot be used for the auto controlling of

the drum level

2) Designing the control logic: The Corrected drum level signal is compared with the desired set

point & hence error signal is generated. Based on the error signal, the raise or lower command goesto the controlling element. Here in the auto controlling of the drum level, we may go for two types of

logic-

iii) Single element control logic: In this only drum level signal is compared with the desired set point

& thus on the basis of the error signal, raise & lower command is sent to the controlling element. Here

in this project we are focusing on the single element controller.

iv) Three element control logic: In this, instead of considering only the drum level we will focus on

the two other parameters which are Total Feed water flow and total steam flow. Designing the three

element controller may be the extension of this project.

2) Designing the controlling element: There are three control elements as follows:a) Electrical/Linear Actuator: A linear actuator is an actuator that creates motion in a straight line as

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Linear actuators are used in machine tools and industrial machinery, in computer peripherals such as

disk drives and printers, in valves and dampers, and in many other places where linear motion is

required. Hydraulic or pneumatic cylinders inherently produce linear motion; many other mechanisms

are used to provide a linear motion from a rotating motor.

b) Pneumatic Actuator: A pneumatic actuator converts energy (typically in the form of compressed

air) into mechanical motion. The motion can be rotary or linear, depending on the type of actuator.

Some types of pneumatic actuators include: Tie rod cylinders

Rotary actuators

Grippers

Rod Less actuators with magnetic linkage or rotary cylinder

Rod Less actuators with mechanical linkage

Pneumatic artificial muscles

Vacuum generators

c) Hydraulic Actuator: A Hydraulic cylinder is a mechanical actuator that is used to give a

unidirectional force through a unidirectional stroke. It has many applications, notably in engineeringvehicles. Hydraulic cylinders get their power from pressurized hydraulic fluid, which is typically oil.

The hydraulic cylinder consists of a cylinder barrel, in which a piston connected to a piston rod moves

back and forth. The barrel is closed on each end by the cylinder bottom (also called the cap end) and

by the cylinder head where the piston rod comes out of the cylinder. The piston has sliding rings and

seals . The piston divides the inside of the cylinder in two chambers, the bottom chamber (cap end)

and the piston rod side chamber (rod end). The hydraulic pressure acts on the piston to do

linear work and motion.

BLOCK DIAGRAM

DESCRIPTION OF BLOCK DIAGRAM

There are two main circuits used in this project. The command for valve actuator can be

given in manual and auto mode both. The circuits for manual & auto command are different.

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In the circuit of manual mode, the main supply is of 230V AC. The supply is given to the AC to

DC converter. The converter converts 230V AC to 24V DC. This DC supply is given to the

dextile, the dextile and limit switches are connected in parallel. The output of dextile is given

to the DC relays. The DC relays provide 24V as input and 230V as output. The output of DC

relay is given to the contactor which accepts 230V as input and output both & the output of

the contactor is fed to the single phase AC motor.

If boundary limits are reached as full open or full close then on giving any further command

will not be executed by the motor.

The energized relay will rotate the motor either in clockwise or in anticlockwise direction

depending upon the energisation. The opening and closing of the valve will depend on the

direction of motor. The motor will control the opening and closing of valve which will control

the level of water in drum. It is necessary to keep track of one thing that at one time only

one relay should get energized either forward relay or backward relay, hence forward or

reverse connectors are used to avoid the simultaneous energization of both forward and

backward relays. The forward relay helps the motor to rotate in clockwise direction and the

backward relay makes the motor to rotate in anticlockwise direction.

In the circuit of auto mode the I 06 R mini card is used. The I-06 R card is used to make the

summator subtractor circuit. The card is uses a low current offset differential amplifier, with

feedback arranged to produce the required computing function. The amplifier which is used

to make this 06 r card is used in non-inverting mode. For current input signals, conditioning

resistors are fitted across the input terminals. These resistors are placed in specific order.

There are two inputs of the I-06 R card as one is reference level and other is variable supply.

The 06 R mini card gives error signal as its output. According to this error signal the trigger

circuit will energize the corresponding relay.

The output of I-06 computing Mini Card which is an error signal will be send to the triggercircuit. The trigger circuit will generate the pulses of +20 V and -20 V which is send to the

forward or backward relays.

The output of the trigger circuit will energize one of the relay either forward or reverse relay.

The 555 timer IC is used in the trigger circuit. The output of the trigger circuit is fed to the

12V dc relays. Then these 12V relays will energize the 24 V DC relays.

CIRCUIT DIAGRAM

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There are two main circuits used in this project. The command for valve actuator can be

given in manual and auto mode both. The circuits for manual & auto command are different.

The circuit for auto command is in parallel with the circuit for manual command.

CIRCUIT DESCRIPTION OF AUTO MODE

CIRCUIT DIAGRAM FOR SET POINT:

The 7805 IC is used for the set input which is given to the I-06R mini card. 20V is given as

input to the 7805 voltage regulator IC. The output of the 7805 is 5V which is constant and we

are using 5V as set point of the I 06 R mini card. The 20v is fed to the pin 1 of IC and output is

being taken from pin 3 of IC

CIRCUIT DAIGRAM FOR VARIABLE INPUT

The output voltage is stabilized and is regulated in the region from 0V until + 15V dc, with

biggest provided current 1 A. The regulation becomes with the R2. The Q1 of is classic power

transistor and it needs it is placed in heat sink, one and heating when it works continuously

in the region of biggest current. The type of transformer is standard in the market. The

variable resistor or potentiometer gives as variable output from 0 to +15V which are given asone of the input of I-06 R mini card.

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I-06R MINI CARD CIRCUIT DIAGRAM

The I-06 R card is used to make the summator subtractor circuit. The card is uses a low

current offset differential amplifier, with feedback arranged to produce the required

computing function. The amplifier which is used to make this 06 r card is used in non-

inverting mode. For current input signals, conditioning resistors are fitted across the input

terminals. These resistors are placed in specific order. There are two inputs of the I -06 R card

as one is reference level and other is the output of potentiometer which is variable in nature.

There are three input pins of this card as 1, 2. And 3 of the I 06 R mini card .There are two

inputs applied to the 06 R mini card to generate the error signal. One is reference or set

point which is applied to the pin 1 of this card and second is variable input which is appl ied

to the pin 2 of the card+20V is applied to the pin 8 of card and -20V is applied to the pin 10

of the card. The +20V and -20V are applied to the card to drive the card. The output is being

taken from the pin 4 of the card with reference to the ground which is at pin 09 of card.

When less than the total available inputs are in use, the unused inputs should be connected

to the common line hence pin 3 is connected to the common line or 0V.

TRIGGER CIRCUIT

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The output of I-06 computing Mini Card which is an error signal will be send to the trigger

circuit. The trigger circuit will generate the pulses of +20 V and -20 V which is send to the

forward or backward relays.

The two comparator inputs (pin 2 & 6) are tied together and biased at 1/2 Vcc through a

voltage divider R1 and R2.Since the threshold comparator wil trip at 2/3 Vcc and the triggercomparator will trip at 1/3Vcc,the bias provided by the resistors R1 & R2 are centered within

the comparators trip limits.

By modifying the input time constant on the circuit,reducing the value of input capacitor (C1)

to 0.001 uF so that the input pulse get differentiated,the arrangement can also be used

either as a bistable device or to invert pulse wave forms.In the later case ,the fast time

combination of C1 with R1 & R2 causes only the edges of the input pulse or rectangular

waveform to be passed. These pulses set and reset the flip-flop and a high level inverted

output is the result.

ELECTRICAL ACTUATOR CIRCUIT

The output of the trigger circuit will energize one of the relay either forward or reverse relay.

The energized relay will rotate the motor either in clockwise or anticlockwise direction

depends on the type of energized relay. The opening and closing of valve will depend on the

direction of motor. The motor will control the opening and closing of valve which will control

the level of water in drum. It is necessary to keep track of one thing that at one time only

one relay should get energized either forward relay or backward relay, hence forward or

reverse connectors are used to avoid the simultaneous energization of both forward and

backward relays.

DEXTILE, LIMIT SWITCH and RELAY PIN DESCRIPTION

The port P12 and P11 gets supply of negative and positive 24 volts respectively. The positive

terminal of limit switch is connected to P4 and P6 terminal of the dextile, negative terminal

of limit switch is connected to fourth port of relay. The port 12 of the dextile is connected to

the eight port of the relay. P1 and P3 of dextile is connected to the fourth port of forward

and backward relay respectively. The connection on port P1 helps to glows yellow colour LED

and green colour LED on P3. The port 3 of the relays gets a supply of 230 volts. NC of

contactor is connected to the second port of relays. The A1 port of both parts of the

contactor is on neutral. A1 port of the first part of contactor is connected to NC of second

part of contactor and vice versa. L1 port of both parts of contactor gets a supply of 230 volts .

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CONCLUSION:

. Practically there are many parameters to be controlled to maintain the level of water in

drum according to the requirement but we have considered only one parameter of flow of

water in our project. The content of steam which is going in turbine depends on the level of

water in drum hence water level should be in control. To fulfill this purpose we had designed

a controlling element which is receiving command by the trigger circuit. The trigger circuit is

correcting the error signal generated by I-06R mini card and providing appropriate command

to the motor.

EXTENSIONS

1) T

riggering circuit may be the economical replace of the 74 R card.

2) I

f drum level is put on auto loop during the lighted up condition of the boiler, there will be

huge saving of monetary losses.

3)

Timely synchronisation of the unit is possible and hence can better serve the society.

COMPONENTS DESCRIPTION

LIMIT SWITCH

Inelectrical engineering a limit switch is a switch operated by the motion of a machine part

or presence of an object. They are used for control of a machine, as safety interlocks, or to

count objects passing a point.

Limit switch is one type Of " Contact Sensor, In that there is Normally Open Contact &

Normally Close Contact, In limit switch there is Plunger it is Directly Connected to NO & NCContact if we press the plunger NO contact become NC & NC contact become NO, Working

Principle same as Contactor (DOL starter) main difference is in contactor There is Coil to

attract the Plunger But In Limit Switch Plunger is Operated Mechanically. Limit Switches is

used mainly for Safety Purpose & to take Feed back for PLC in Automation industries.

Many limit switches have three terminals. One is the normally closed contact, another the

normally open contact and the third is the common that switches between these two as the

mechanism is moved.

The limit switch is mounted in such a way when the mechanism driven by motor reaches one

of the limit positions, it will engage the limit switch at that position. This will cause NC

contacts of that switch to open and its NO to close.

RELAY

A relay is an electricallyoperated switch. Many relays use anelectromagnetto operate a

switching mechanism mechanically, but other operating principles are also used. Relays are

used where it is necessary to control a circuit by a low-power signal (with complete electrical

isolation between control and controlled circuits), or where several circuits must be

controlled by one signal. The first relays were used in long distance telegraph circuits,

repeating the signal coming in from one circuit and re-transmitting it to another. Relays wereused extensively in telephone exchanges and early computers to perform logical operations.

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parts, instead using a semiconductor device to perform switching. Relays with calibrated

operating characteristics and sometimes multiple operating coils are used to protect

electrical circuits from overload or faults; in modern electric power systems these functions

are performed by digital instruments still called "protective relays".

It is a protective device. It can detect wrong condition in electrical circuits by constantly

measuring the electrical quantities flowing under normal and faulty conditions. Some of theelectrical quantities are voltage, current, phase angle and velocity.

CONTACTOR RELAY

Acontactor is a very heavy-duty relay used for switching electric motors and lighting loads,

although contactors are not generally called relays. Continuous current ratings for common

contactors range from 10 amps to several hundred amps. High-current contacts are made

with alloys containingsilver. The unavoidable arcing causes the contacts to oxidize;

however, silver oxide is still a good conductor. Such devices are often used for motor

starters. A motor starter is a contactor with overload protection devices attached. Theoverload sensing devices are a form of heat operated relay where a coil heats a bi-metal

strip, or where a solder pot melts, releasing a spring to operate auxiliary contacts. These

auxiliary contacts are in series with the coil. If the overload senses excess current in the load,

the coil is de-energized. Contactor relays can be extremely loud to operate, making them

unfit for use where noise is a chief concern.

A simple electromagnetic relay consists of a coilof wire wrapped around asoft iron core,an

iron yoke which provides a low reluctance path for magnetic flux, a movable ironarmature,

and one or more sets of contacts (there are two in the relay pictured). The armature is

hinged to the yoke and mechanically linked to one or more sets of moving contacts. It is held

in place by aspringso that when the relay is de-energized there is an air gap in the magneticcircuit. In this condition, one of the two sets of contacts in the relay pictured is closed, and

the other set is open. Other relays may have more or fewer sets of contacts depending on

their function. The relay in the picture also has a wire connecting the armature to the yoke.

This ensures continuity of the circuit between the moving contacts on the armature, and the

circuit track on theprinted circuit board(PCB) via the yoke, which is soldered to the PCB

When anelectric currentis passed through the coil it generates a magnetic fieldthat

activates the armature and the consequent movement of the movable contact either makes

or breaks (depending upon construction) a connection with a fixed contact. If the set of

contacts was closed when the relay was de-energized, then the movement opens the

contacts and breaks the connection, and vice versa if the contacts were open. When the

current to the coil is switched off, the armature is returned by a force, approximately half as

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When the coil is energized withdirect current, adiodeis often placed across the coil to

dissipate the energy from the collapsing magnetic field at deactivation, which would

otherwise generate a voltage spikedangerous to semiconductorcircuit components. Some

automotive relays include a diode inside the relay case. Alternatively, a contact protection

network consisting of a capacitor and resistor in series (snubber circuit) may absorb the

surge. If the coil is designed to be energized with alternating current(AC), a small copper

"shading ring" can be crimped to the end of the solenoid, creating a small out-of-phase

current which increases the minimum pull on the armature during the AC cycle.A solid-state relay uses a thyristoror other solid-state switching device, activated by the

control signal, to switch the controlled load, instead of a solenoid. An optocoupler(a light-

emitting diode(LED) coupled with aphoto transistor) can be used to isolate control and

controlled circuits.

OPERATING PRINCIPLE

Unlike general-purpose relays, contactors are designed to be directly connected to high-

current load devices. Relays tend to be of lower capacity and are usually designed forboth normally closed and normally open applications. Devices switching more than 15

amperes or in circuits rated more than a few kilowatts are usually called contactors. Apart

from optional auxiliary low current contacts, contactors are almost exclusively fitted with

normally open contacts. Unlike relays, contactors are designed with features to control and

suppress the arc produced when interrupting heavy motor currents.

When current passes through theelectromagnet, a magnetic field is produced, which attracts

the moving core of the contactor? The electromagnet coil draws more current initially, until

itsinductanceincreases when the metal core enters the coil. The moving contact is propelled

by the moving core; the force developed by the electromagnet holds the moving and fixed

contacts together. When the contactor coil is de-energized, gravity or a spring returns the

electromagnet core to its initial position and opens the contacts.

For contactors energized withalternating current, a small part of the core is surrounded with

a shading coil, which slightly delays the magnetic flux in the core. The effect is to average out

the alternating pull of the magnetic field and so prevent the core from buzzing at twice line

frequency.

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7805 VOLTAGE REGULATOR IC

The 7805 is a self-contained fixedlinear voltage regulatorintegrated circuit.. The voltage

regulator ic family is commonly used in electronic circuits requiring a regulated power supply

due to their ease-of-use and low cost. The 7805 line is positive voltage regulators: they

produce a voltage that is positive relative to a common ground.

7805 ICs have three terminals and are commonly found in theTO220form factor, although

smaller surface-mount and largerTO3packages are available. These devices support an

input voltage anywhere from a couple of volts over the intended output voltage, up to a

maximum of 35 to 40 volts depending on the make, and typically provide 1 or

1.5amperesofcurrent(though smaller or larger packages may have a lower or higher current

rating).

7805 series ICs do not require additional components to provide a constant, regulated

source of power, making them easy to use, as well as economical and efficient uses of space.

Other voltage regulators may require additional components to set the output voltage level,

or to assist in the regulation process. Some other designs (such as a switched-mode power

supply) may need substantial engineering expertise to implement.

7805 series ICs have built-in protection against a circuit drawing too much power. They have

protection against overheating and short-circuits, making them quite robust in mostapplications. In some cases, the current-limiting features of the 7805 devices can provide

protection not only for the 7805 itself, but also for other parts of the circuit.

7805 ICs are easy to use and handle but these cannot give an altering voltage required so

LM317 series of ICs are available to obtain a voltage output from 1.25 volts to 37 volts.

2N3055 TRANSISTOR

The 2N3055 is a siliconNPNpowertransistorintended for general purpose applications.

Thehorizontal output transformerfrom a CRTtype TV can be driven using just two resistorsand a 2N3055 infly back mode, transforming a low voltage, such as 12 volts, into several

kilovolts. The output is very low current, so there is a minimal chance of dangerous electric

shock. However, the design is limited by the 2N3055's ability to handle this sort of circuit,

and will overheat and quickly fail from the inductive voltage feedback spikesfrom the

transformer. Hobbyists would, after gaining an understanding of high voltage, then move on

to higher power circuits and transformers. This transistor must be counted among the

hobbyists as the most used power transistor, after being used in audio power amplifier with

powers ranging from 10W to 400W.

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555 TIMER IC

The 555 timer IC is an integrated circuit (chip) used in a variety of timer,pulse generation,

and oscillatorapplications. The 555 can be used to provide time delays, as anoscillator, and

as aflip-flop element.Derivatives provide up to four timing circuits in one package.

The IC was designed in 1971 by Hans R. Camenzind under contract to Signetics,which was

later acquired byPhilips.Depending on the manufacturer, the standard 555 package includes

25 transistors, 2 diodesand 15 resistorson a siliconchip installed in an 8-pin mini dual-in-line

package (DIP-8).[2]Variants available include the 556 (a 14-pin DIP combining two 555s on

one chip), and the two 558 & 559s (both a 16-pin DIP combining four slightly modified 555s

with DIS & THR connected internally, and TR is falling edge sensitive instead of level

sensitive). There is no 557.

The NE555 parts were commercial temperature range, 0 C to +70 C, and the SE555 part

number designated the military temperature range, 55 C to +125 C. These were available

in both high-reliability metal can (T package) and inexpensive epoxy plastic (V package)

packages. Thus the full part numbers were NE555V, NE555T, SE555V, and SE555T. It has

been hypothesized that the 555 got its name from the three 5k resistors used within, but

Hans Camenzind has stated that the number was arbitrary.

Pin Diagram

The connection of the pins for a DIP package is as follows:

Pin Name Purpose

1 GND Ground, low level (0 V)

http://en.wikipedia.org/wiki/Integrated_circuithttp://en.wikipedia.org/wiki/Integrated_circuithttp://en.wikipedia.org/wiki/Timerhttp://en.wikipedia.org/wiki/Timerhttp://en.wikipedia.org/wiki/Timerhttp://en.wikipedia.org/wiki/Electronic_oscillatorhttp://en.wikipedia.org/wiki/Electronic_oscillatorhttp://en.wikipedia.org/wiki/Oscillatorhttp://en.wikipedia.org/wiki/Oscillatorhttp://en.wikipedia.org/wiki/Flip-flop_elementhttp://en.wikipedia.org/wiki/Flip-flop_elementhttp://en.wikipedia.org/wiki/Flip-flop_elementhttp://en.wikipedia.org/wiki/Hans_R._Camenzindhttp://en.wikipedia.org/wiki/Hans_R._Camenzindhttp://en.wikipedia.org/wiki/Signeticshttp://en.wikipedia.org/wiki/Signeticshttp://en.wikipedia.org/wiki/Signeticshttp://en.wikipedia.org/wiki/Philipshttp://en.wikipedia.org/wiki/Philipshttp://en.wikipedia.org/wiki/Philipshttp://en.wikipedia.org/wiki/Transistorhttp://en.wikipedia.org/wiki/Transistorhttp://en.wikipedia.org/wiki/Transistorhttp://en.wikipedia.org/wiki/Diodehttp://en.wikipedia.org/wiki/Diodehttp://en.wikipedia.org/wiki/Resistorhttp://en.wikipedia.org/wiki/Resistorhttp://en.wikipedia.org/wiki/Siliconhttp://en.wikipedia.org/wiki/Siliconhttp://en.wikipedia.org/wiki/DIP-8http://en.wikipedia.org/wiki/DIP-8http://en.wikipedia.org/wiki/555_timer_IC#cite_note-2http://en.wikipedia.org/wiki/555_timer_IC#cite_note-2http://en.wikipedia.org/wiki/Ohmhttp://en.wikipedia.org/wiki/Ohmhttp://en.wikipedia.org/wiki/Ohmhttp://en.wikipedia.org/wiki/File:555_Pinout.svghttp://en.wikipedia.org/wiki/Ohmhttp://en.wikipedia.org/wiki/555_timer_IC#cite_note-2http://en.wikipedia.org/wiki/DIP-8http://en.wikipedia.org/wiki/Siliconhttp://en.wikipedia.org/wiki/Resistorhttp://en.wikipedia.org/wiki/Diodehttp://en.wikipedia.org/wiki/Transistorhttp://en.wikipedia.org/wiki/Philipshttp://en.wikipedia.org/wiki/Signeticshttp://en.wikipedia.org/wiki/Hans_R._Camenzindhttp://en.wikipedia.org/wiki/Flip-flop_elementhttp://en.wikipedia.org/wiki/Oscillatorhttp://en.wikipedia.org/wiki/Electronic_oscillatorhttp://en.wikipedia.org/wiki/Timerhttp://en.wikipedia.org/wiki/Integrated_circuit

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voltage.

3 OUTThis output is driven to

approximately 1.7V below+VCCor GND.

4 RESET A timing interval may be reset by

driving this input to GND, but the timing

does not begin again until RESET rises

above approximately 0.7 volts.

Overrides TRIG which overrides THR.

5 CTRL"Control" access to the internal

voltage divider (by default, 2/3 VCC).

6 THRThe interval ends when the voltage

at THR is greater than at CTRL.

7 DIS

Open collectoroutput; may

discharge a capacitor between intervals.

In phase with output.

8 VCCPositive supply voltage is usually

between 3 and 15 V.

Note-PIN 5 is also called the CONTROL VOLTAGE pin by applying a voltage to the CONTROLVOLTAGE input you can alter the timing characteristics of the device. In most applications,

the CONTROL VOLTAGE input is not used. It is usual to connect a 10 nF capacitor between

pin 5 and 0 V to prevent interference. The CONTROL VOLTAGE input can be used to build an

astable with a frequency modulated output.

SPECIFICATION

These specifications apply to the NE555. Other 555 timers can have different specifications

depending on the grade (military, medical, etc.).

Supply voltage (VCC) 4.5 to 15 V

Supply current (VCC= +5 V) 3 to 6 mA

Supply current (VCC= +15 V) 10 to 15 mA

Output current (maximum) 200 mA

Maximum Power dissipation 600 mW

Power consumption (minimum operating) 30 mW@5V, 225 mW@15V

O ti t t 0 t 70 C

http://en.wikipedia.org/wiki/Vcchttp://en.wikipedia.org/wiki/Vcchttp://en.wikipedia.org/wiki/Vcchttp://en.wikipedia.org/wiki/Vcchttp://en.wikipedia.org/wiki/Vcchttp://en.wikipedia.org/wiki/Open_collectorhttp://en.wikipedia.org/wiki/Open_collectorhttp://en.wikipedia.org/wiki/Open_collectorhttp://en.wikipedia.org/wiki/Vcc

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Need for communication

Among different sites

Enterprise Resource Planning(ERP)

An ERP system can either reside on a centralized server or be distributed

across modular hardware and software units that provide "services" and

communicate on a local area network. The distributed design allows a business

to assemble modules from different vendors without the need for the placement

of multiple copies of complex and expensive computer systems in areas which

will not use their full capacity

Manufacturing

Engineering, bills of material, work orders, scheduling, capacity, workflow

management, quality control, cost management, manufacturing process,

manufacturing projects, manufacturing flow

Supply chain management

Order to cash, inventory, order entry, purchasing, product configurator,

supply chain planning, supplier scheduling, inspection of goods, claim

processing, and commission calculationFinancials

General ledger, cash management, accounts payable, accounts receivable,

fixed assets

Project management

Costing, billing, time and expense, performance units, activity management

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Human resources

Human resources, payroll, training, time and attendance, rostering, benefits

Customer relationship management

Sales and marketing, commissions, service, customer contact, call-center

support

Data services

Various "self-service" interfaces for customers, suppliers and/or employees

Access control

Management of user privileges for various process.

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Types of networks used by NTPC

NTPC uses 3 different types of networks for the purpose of

communicationamong its various sites. These are listed below:

MPLS Network

ISDN Network

VSAT Network

MPLS Network

MPLS Network is the Multiple Protocol Level Shift Network.It provides a

network speed of 2 mbps to 34 mbps. It is the primary network which is

used

by the NTPC sites.

ISDN Network

ISDN is the Integrated Service Digital Network. This Network is

provided

by operators like BSNL or VSNL, in the form of a leased line

which is a

dedicated line. The speed provided is up to 2 mbps.

VSAT Network

VSAT or Very Small Aperture Network is a satellite based

network. It is

used as a backup network. The speed provided by VSAT is about 2mbps.

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Launch Date 28.09.2003

INSAT-3E is the fourth satellite launched in the INSAT-3 series. It is an exclusive

communication satellite to further augment the communication services that are

being provided by the INSAT System. Weighing 2775 kg at lift-off, INSAT-3E

carries 24 Normal C-band and 12 Extended C-band transponde

VSAT Network

Definition: A Very Small Aperture Terminal(VSAT), is a two-way

satellite ground

station with a dish antenna that is smaller than 3 meters (most VSATantennas

range from 75 cm to 1.2 m). VSAT data rates typically range fromnarrowband

Mission Communication

Spacecraft

Mass

2,775 Kg (Mass at

Lift-off)

1218 Kg (Dry mass)

Launch date September 28, 2003

Launch site French Guyana

Launch

vehicle

Ariane5-V162

orbit Geostationary Orbit

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up to 4 Mbit/s. VSATs access satellites in geosynchronous orbit to relay data

from small remote earth stations (terminals) to other terminals (in mesh

configurations) or master earth station "hubs" (in star configurations).

VSATs access satellites in geosynchronous orbit to relay data fromsmall

remote earth stations (terminals) to other terminals (in mesh configurations)

or

master earth station "hubs" (in star configurations).

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Satellite communication concept

Note:

HPA High Power Amplifier (Earth Station equipment that

amplifies the

transmit RF signal)

CPE Customer Premises Equipment (eg. Telephone, PABX, Ethernet

hub,

host server etc.)

VSAT Specifications

Antenna diameter: 11 m

Traffic Capacity: 9.6 kbps2 mbps

Diagram

Frequency Bands:

C-Band (4/6 GHz)

Ku-Band (12/14 GHz)

Ka-Band (20/30 GHz)

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Network: Point-to-Point

Configuration: Point-to-Multipoint

Equipment List:

Antenna;

Outdoor Unit: HPA, LNA, SSPA(Solid State Power Amplifier)

Indoor Unit : Chassis

Note:

Antenna size is used to describe the ability of antenna to amplify

the signal

strength;

Outdoor unit (ODU) is connected through a low-loss coaxialcable to the

indoor unit (IDU) called IFL (Inter-facility Link)

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AJAY KUMAR GARG ENGINEERING COLLEGE

27, DELHI-HAPUR BYPASS ROAD

GHAZIABAD-201009

A

INDUSTRIAL TRAINING REPORT

ON

CONTROL AND INSTRUMENTATION

AT

NTPC BADARPUR,NEW DELHI

Submitted by- Under the Guidance of

Name-JANKI Mrs Rachna Singh Bhal

Year-4th AGM (HR)

Branch-ECE NTPC (Badarpur).

Date-11-8-2014

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AJAY KUMAR GARG ENGINEERING COLLEGE

27, DELHI-HAPUR BYPASS ROAD

GHAZIABAD-201009

TRAINING CERTIFICATE

This is to certify that Ms. JANKI D/o Dr MANOJ KUMAR MISHRA student of AJAY

KUMAR GARG ENGINEERING COLLEGE B.Tech.3rd year ECE branch has undergone

Industrial training in topic-CONTROL AND INSTRUMENTATION from 17-06-2014 to17-07-2014.

Gp.Capt.(Retd.)P.K.Chopra VSM Gp.Capt.(Retd.)P.K.Chopra VSM

HoD-ECE Prof. & HoD-T&P