javed nt pc project

7/31/2019 Javed Nt Pc Project

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1-ITRODUCTIO

National Thermal Power Corporation is a big name in power generation world.

It is government undertaking company in India which is among world largest and

most efficient power generating company. In forbs list of worlds 2000 largest

companies for the year 2007 NTPC Ltd. Occupies 4th

place and glowing everyday to

become a power plant.

It is main power generating unit in India feeding approx 60% of the total

needs. It has total installed capacity of 29,344 MW. It has 15 coal based power station

(23395MW) and 7 gas based power station (3955 MW) and 4 power station in joint

venture (1794MW) . The company has power generating facility in all major region of

the country. It plans to be 75,000MW producing company by 2017.

NTPC has gone beyond the thermal power generation. It has diversified into

hydro power. Coal mining, power equipment manufacturing, oil and gas exploration,

power trading and distribution etc. NTPC is now in the entire power value chair .


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2-ABOUT TPC KAHALGAO

NTPC Kahalgaon is one of the project in eastern region contributing to

NTPCs good health its unit in Bihar was set up in the year 1987 with the technical

collaboration with USSR.

It is situated at Kahalgaon 30 km from Bhagalpur town. The nearest airport

to it is in Patna which is the capital if state Bihar.

The total land acquired by NTPC Khstpp is 3360 acres among which 883

acres for plant,432 acre for township,522 acres for MGR. 1395 acres for DYKE, 28

acres for makeup water, 70 acres for system approach and 30 acres for other. It is a

thermal power plant that uses coal, as fuel.

The coal fields (ECL, LALMATIA, ASANSOL and MCL) which supplies

India l Bituminous coal whose calorific value varies between 2700 kcal per kg to

3000 kcal/kg and water requirement is met from the river Ganga.

80% of total power generated is supplied to west Bengal, 15% to Bihar, 5% to

Jharkhand. There are total 10 lines outgoing from plant. 4lines to Bihar Shariff, 2

lines to Patna, 2 lines to naithan and 2 lines to Farakka.


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3-OVERVIEW OF TPC KAHALGAO

Location : Bihar, Dist. Bhagalpur, P.O. Deeptinagar

Installed Capacity : 1840 MW

Area : 3360 Acres

Configuration : Stage-I 4X210 MW

: Stage-II Phase-I 2X500MW

: Stage-II Phase-II 1X500MW

Source of Fuel : Rajmahal Hurra, Chuperbita of the Eastern Coalfield Ltd.

Fuel Requirements: Stage-I 4.1 MT/Yr.

Stage-II 6.62 MT/Yr (phase-I)

3.07 MT/Yr. (Phase-II)

Makeup Water : 7500 M3/Hr (Stage-I)

6000 M3/Hr (Stage-II)

CW System : Closed Cycle, Induced Draft, Cross Flow Cooling Towers

Beneficiary States : The states and Union Territories of NR, WR, ER, & SR.

Approved Project Cost : 1715 Crors (Stage-

I)

6330 Crors (Stage-II)

Synchronization : Unit-1 1992 Unit-2 1994

Unit-3 1995 Unit-4 1996

Commercialization: Unit-1 Jan 1995 Unit-2 April 1995

Unit-3 Feb 1996 Unit-4 Aug 1996

Unit-5 1st

Aug 2008 Unit-6 30th

2008


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4-BASIC FUCTIO OF THERMAL PLAT

Figure No.1(basic function of thermal plant)

4.1) COAL TO ELECTRICITY:

The thermal power plant uses a dual (vapour +liquid) phase .It is closed cycle

to enable the working fluid to be used again and again. The cycle used is "Ranking

cycle "modified to include super heating of steam, regenerative feed water heating

and reheating of steam.

4.2) BOILER-

A boiler or steam generator essentially is a container into which water can be

fed and steam can be taken out of desired pressure, temperature and flow. This calls

for the application of heat on the container. For this boiler should have a facility to

burn a fuel and release the heat. The function of boiler or steam generator thus can bestated as -

I. To convert chemical energy of the fuel into heat energy.II. To transfer this heat energy to water for evaporation as well to steam for

superheating.


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4.3) ECOOMIZER-

These are provided in the boilers to improve the efficiency of the boiler by

extracting the heat from flue gases and add it as either sensible heat alone or sensible

heat or latent heat to the feed water before the water enters the evaporating surface of

the boiler

Provision of economizer in a boiler has two advantages-

i) As the economizer recover the heat in flue gas that leaves the boiler and

transfer to working fluid there will be savings in fluid consumption.

ii) As the feed water is preheated in the economizer and enters the boiler tubes

at an elevated temperature the heat transfer area required will be reduced

considerably.

4.4) BOILER DRUM-

Figure no.2 (boiler drum, superheater, reheater, and economizer)

In a sub critical recirculation boiler, the drum plays an important functional

role in the erection of power boiler; the lifting of the boiler drum is the first milestone.

The fictions of drum are:-

a) Separation of saturated steam from the steam-water mixture produces by


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the evaporating tubes.

b) Mixing feed water from economizer and water separated from steam -water

mixture, are re-circulated through the evaporating tubes.

c) Carrying out blown down for reduction of boiler water salt concentration

d) Treatment of boiler water by chemicals.

As the quantity of water contained in the drum below the water level is relatively

small compared to the total steam output, the function of water storage in drum is not

significant.

4.5) SUPERHEATERS-

Super heaters are provided in the boiler to raise the steam the steam

temperature above the saturation temperature by absorbing the heat from the flue gas .

It has many advantages-

i) By increasing the temperature of the steam , the useful energy that can be

recovered economically increases thus the efficiency of the cycle.

ii) Superheating of steam eliminates the condensation of steam during

transporting of steam in pipelines and inside the early stage of turbine which is

harmful to the turbine blades and the pipelines.

iii) Limits the work done by turbine stage to avoid excessive erosion of blades.

4.6) REHEATERS -

Development of large capacity steam turbines with more number of stages

posed a problem of retaining the steam with vapor phase till the last stage. It is

because even with a larger steam turbine the inlet steam temperature is kept at 540 C

only due super heater limitation. To overcome this problem it becomes necessary to

raise the temperature after part of energy is extracted from it in the steam turbine This

is called reheating of steam which increases the cycle efficiency .This reheating of

steam is done in the boiler which supplies the superheated steam to the turbine , itself

at the heating surfaces called Re-heaters.

4.7) FORCED DRAUGHT-In this system a fan called forced draught fan is installed at the inlet of boiler .

This fan forces the atmospheric air through the boiler furnace and pushes out the hot

gases from the furnace through super heaters, re heaters, economizers, air heaters etc.

to the stack . This steam is under a positive pressure. Utmost care is necessary to seal

all the openings of the boiler so that the hot gases inside the boiler do not leak out.


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4.8) IDUCED DRAUHGHT-

Here a fan called induced draught fan is provided at output of the boiler that is

just before the chimney .This fan sucks the hot gases from the furnace through the

super heaters, repeaters, economizer's air heaters etc and discharges the gases into the

chimney. This results the furnace pressure lower than the atmosphere and effects the

flow if air from outside the furnace. In induced draught system the entire boiler is at

pressure below atmosphere. Due to this air can be drawn into the boiler setting. This

leakage of air into the boiler is known as air ingress.

4.9) TURBIE-

Figure No.3 (turbine and generator)

A turbine a form of engine requires in order functioning a suitable working

fluid, a source of high grade energy and a sink for low grade energy. When a fluid

flows through a turbine, a part of energy content is continuously extracted and

converted into useful mechanical work. Steam and gas turbines use heat energy, while

water turbine uses pressure energy.

A steam turbine has two main parts are cylinder and rotor. The cylinder

(stator) is made up of steel or cast iron housing usually divided at horizontal

centerline. Its halves are bolted together for easy access.

The cylinder contains fixed blades, vanes and nozzles that direct steam into

the moving blade carried by the rotor. Each fixed blade set is mounted in diaphragms


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located in front of each disc of the rotor, or directly in the casing. A disc and a

diaphragm pair is one stage. Steam turbines can have many stages. The rotor is

rotating shaft that carries the moving blades on the outer edges of each disc or drum.

The blades rotate as rotor revolves.

4.10) CODESER-

The steam after condensing in a condenser is known as condensate, is

Figure No.4( condenser)

extracted out of the condenser hot well by condensate pump and taken to the dearator,through ejectors , gland steam cooler and series of LP heaters.

4.11) COOLIG WATER SYSTEM-

Figure No.5(cooling water system)

4.12) CODESATE PUMPS-

The function of these pumps is to pump out the condensate to the deaerator.


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4.13) DEARATOR-

It is used to remove unwanted gases which are mixed in cold water during

condensing of steam.

Figure No. 6(Dearator)

4.14) BOILER FEED PUMP-

From the condenser the condensate is pumped through low pressure heaters by

the extraction pump, after which its pressure is raised to boiler pressure by the boiler

feed pump. It is passed through further heaters to the economizers and the boiler for

reconversion of steam

5-IT DEPARTMET

IT department was formerly known by EDP. EDP is abbreviated from of

Employee Data Process. IT department deals with IT requirement setup and day to

day maintenance within the whole plant. Network of fiber cable has been laid in the

whole plant to perform the required function.

It has a built in server to cater to its IT requirement. Different system is there

which are used to help various departments in their effective functions of routine tasks

so as to help in faster and effective decision making.

5.1) FUCTIOS OF IT DEPARTMET-

1. System investigation2. System analysis3. System design.4. Programming5. System implementation


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6. System maintenance7. Prototyping of systems developed at corporate.8. Maintaining data base system9. Hardware selection10.Software selection11.Computer security

THREE MAI PART OF IT DEPARTMET-

1. Satellite communication2. Networking3. Telephone exchange

5.2) SATELLITE COMMUICATIO-

The origins of Satellite Communication can be traced back to an article written by

Mr. Arthur C. Clarke in the British Radio magazine Wireless World in 1945. Satellitecommunication began much latter in October 1957 with the lunch by U.S.S.R. of

small satellite called Sputnik I. The first true communication satellites, Telstar I and

II, were launched in July 1962 and May 1963. Since then there has no looking back.

Satellite communication offers a great number of advantages over terrestrial

links, that is why, it is preferred over terrestrial communication, namely :-

1-High availability minimal/nil fading.

2-No last mile problem.

3-Extensive coverage-Hemi/Zonal/Spot.

4-Broad cast nature allows easy point to multipoint links.

5-Easy scalability and expandability of network.

6-Security and secrecy can be adequately addressed.

7-Less prone to failure due to natural calamities.

The disadvantages being:-

1-High up- front investment in ground segment.

2-High recurring cost on satellite segment.A Sattcom exchange has also been provided in NTPC-Kahalgaon, which

caters to the communication needs all its 96 employees. The outdoor unit basically

consists of the Antenna. The indoor unit comprises a modem, multiplexer, router,

DAMA, DTE, EPBX.The users can connect to the worldwide web or the companys

internet using this system. Using a PC the users can connects to the company LAN via


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a modem and then via server all the outside mails are router to the Proxy server. From

the router the data is routed to the multiplexer from where it goes to the RFT via a

modem. The data is transmitted via the antenna and the satellite to the NTPC earth

station at Muradnagar (now NOIDA). To connect to the Corporate Center a 2Mbps

micro wave link is used. A proxy server is also present in the Corporate Center from

where it connects to the Internet world via CGI and MTNL/BSNL server.

5.21) PRIVATE BRACH AUTOMATIC EXCHAGE-

The EPBAX connects to the main plant telephone exchange as well as a

member of subscribers. These provide the facility of voice communication via

satellite to the users. This is particularly useful in case of terrestrial links, which are

much more damage prone. GDAMS data is also sent to the corporate centre using this

link, as is illustrated in figure. A brief description of the component is given below:-

5.22) SATELLITE-

The third transponder of INSAT-3E with a bandwidth of 18MHz has been

allocated to NTPC to cater to its communication purposes. The bandwidth was

updated to 27MHZ on 19th

of July, 2005.The Kahalgaon satellite Communication

Plan is given below: -

Satellite : INSAT 3E

Location : 55 DEG EAST

Transponder No.:

3

Transponder Bandwidth : 27MHz (6012.00MHz-

6039.00MHz)

Beacon Frequency : 4190.97MHz

Polarization : E/S U/L LINEAR HORIZONTAL

E/S DN/L LINEAR VERTICAL

MCPC Stn. Spt Tx. Setting : 6025MHz

MCPC Stn. Setting : 3800MHz

5.23) ATEA-

The antenna is of CASs grain configuration using shaped reflector

technique to optimize receive gain to noise ratio and the corrugation technique for

primary horn feed to get better symmetry and minimum side lobe of the radiation

pattern. The antenna specification is given below:-


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Type : LIMITED STEERABLE AZ-EL MOUNT

Feed And Reflector : 7.5M dia. CASSEGRAIN WITH SHAPED

REFLECTOR

Tracking : MANUAL DRIVE, AUTO STEP TRACK

EL +5deg - +90deg

AZ -20deg - +20 deg

TX 5.850-6.425GHz

Rx 3.700-4.200GHz

Polarization : LINEAR ORTHOGONAL AND CIRCULAR

6GHz BAND- 51+20logf/6 dB

4GHz BAND 47.5+20logf/4dB

Power Handling

Capacity

: 5KW C W

Antenna Weight : 9 TONNES (Approx)

5.24) TRASCIEVER-

The AAV680 C-Band single Package Transceiver ODU interfaces with the

70MHz/140MHz Indoor Unit having bandwidths of + 18MHz.

In Single Package RF Transceiver there 70 or 140 MHz if input from the indoor

modulation to an RF signal in the C-Band, transmission via antenna and down convert

the L-Band signal (950 1450 MHz) to an IF signal of 70/140 MHz for the

demodulator.

It designed as a single PCB. All SSPA configurations are designed as soft

boards bounded onto aluminum base plates. A low noise amplifier is provided which

receives the weak downlink signal (3.625-4200MHz) and amplifies it to the correct

level before sending it to the SPT for frequency down conversion. It uses HEMT

devices to achieve low noise, high gain and low distortion amplification features. A

Booster is provided to boost up the transmit power of the signal from SPT. For better

reliability, two streams of outdoor C-Band and Ex C-Band transceivers have been

provided. A low noise amplifier is provided which receives the weak downlink signal

(3.625-4.200MHz) and amplifies it to the correct level before sending it to the SPT for

frequency down conversion. It uses HEMT devices to achieve low noise, high gain

and low distortion amplification features. A Booster is provided to boost up the

transmit power of the signal from SPT.


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For better reliability, two streams of outdoor C-Band and Ex C-Band

transceivers have been provided. Redundancy switching equipment performs the

switchover operation when a fault is detected at any one of the streams. Switchover

can be auto/manual and results in less than half a second of traffic interruption.

Independent path switching between the transceivers is allowed. There is a LNA

device. It receives very weak down link signal and amplifies it to the right level

before sending to SPT for the frequency down conversion. This procedure uses High

Electron Mobility Transistor (HETM) for low noise, high gain, and low distortion in

amplification. It requires 12 V DC. Another equipment is used named BOOSTER.

This is used to boost the transmit power of signal from SPT. It has two pats.

1. Power supply board-This converts AC to DC for SSPA.2. SSPA (Solid State Power Amplifier)-This receives RF power from SPT and

amplifies to correct power level.

5.25) RCU-

The redundancy control unit is supplied with +12 or +15 V DC via agile

transceivers. The unit contains-

1. Monitor & control (M & C ) module.2. Window access panel (WAP ).3. IF input power splitter.4. IF output switch.

5.26) M & C-

This module comes with an Intel based microcontroller to link the monitor

and control functions from the outdoor RCU to the indoor DTE (usually PC).

To active remote /local mode, toggle the DIP switch at the outdoor RCU window

access panel.

5.27) MODEM-

The word "modem" is a contraction of the words modulator-demodulator.

The digital satellite modem serves as an interface between the users data terminal

equipment and the IF frequency interface with the up/down converter. The UMOD

has been configured for full duplex operation. The transmit and receive paths are

independent for most applications. In the transmit direction the UMOD accepts user

data at the common interface module (CIM) and directs it across the backplane to the

transmit portion of the terrestrial data interface which converts the users electrical


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format to the format used in UMOD. The data is directed to the optional internal

framing unit for processing and then to the UMOD motherboard. On the motherboard

the data is sent to the channel encoder where scrambling, differential encoding & FEC

encoding is performed. The data is then routed to the transmit filter for digital filtering

and interpolation; then passed to the modulator where the signal is PSK modulated

onto an IF carrier provided by the transmit synthesizer. This modulated carrier is then

amplified in the IF stage, then routed for transmission across the backplane to the IF

OUT connector on the IF panel. In the receive direction the IF signal is input at the IF

IN connector on the IF Panel, passed across the backplane and received by the receive

IF processor on the UMOD motherboard which performs low noise amplification,

automatic gain control and filtering. The signal is then routed to the receive

synthesizer and demodulator where the IF carrier is removed by either BPSK or

QPSK demodulation. The resulting base band data is then directed to the channel

decoder where it is FEC decoded, differentially decoded and descrambled. The data

then passes through the optional IFU daughter card where defaming and other

processing takes place. The data is then routed to the receive portion of the terrestrial

data interface daughter card which converts the receive data and clock to appropriate

formats and directs it across the backplane to the CIM where they can be accessed by

the user.

5.28) MULTIPLEXER-

The Kilomux is an advanced, highly versatile user configurable modular TDM

system providing an efficient method for transmitting data, voice and fax over digital

data services. Its main functions are:-

1. Multiplexing/De-multiplexing operation2. System management3. Interfacing with the optional external system management.

The basic Kilomux system consists of two kilomux units interconnected with each

other. Two main links are there to provide for standby redundancy for the main link.

The Kilomux uses permanent on-demand allocation of main link bandwidth.

The Kilomux is designed for unattended operation. A complete collection of

parameters configuring the kilomux system and each of its modules is determined by

a database which is stored in the non-volatile memory of the Kilomux control module.

Kilomux can store two different databases and can be configured to switchover


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automatically between databases per requirement. It is provided with alarm buffer as

well as LED indicator to display in real time the main link and power supply status.

5.29) ROUTER-

Routers are specialized computers that send your messages and those of every

other Internet user speeding to their destinations along thousands of pathways.. These

are crucial devices that let messages flow between networks rather than within

networks. A router has two separate but related jobs:

(i) the router ensure that information doesn't go where it's not needed. This is

crucial for keeping large volumes of data from clogging the connections of "innocent

bystanders."

(ii) The router makes sure that information does make it to the intended destination.

It joins the two networks, passing information from one to the other and, in some

cases, performing translations of various protocols between the two networks. It also

protects the networks from one another, preventing the traffic on one from

unnecessarily spilling over to the other. As the number of networks attached to one

another grows, the configuration table for handling traffic among them grows, and the

processing power of the router is increased. A configuration table is a collection of

information, including:

(i) Information on which connections lead to particular groups of addresses

(ii) Priorities for connections to be used.

(iii) Rules for handling both routine and special cases of traffic.

ROUTIG OF PACKETS-

The office network connects to the router using an Ethernet connection.

There are two connections between our router and the ISP. One is via the satcom

system and the other via the BSNL ISDN line as is illustrated in figure I. This way the

ISDN line is held as an insurance against a problem with the other faster

connection. In addition to routing packets from one point to another, the router has

rules limiting how computers from outside the network can connect to computersinside the network, how the network appears to the outside world, and other security

functions. While most companies also have a special piece of hardware or software

called a firewall to enforce security, the rules in a router's configuration table are

important to keeping a company's (or family's) network secure.One of the crucial

tasks for any router knows when a packet of information stays on its local network.


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For this, it uses a mechanism called a subnet mask. The subnet mask looks like an IP

address and usually reads "255.255.255.0." This tells the router that all messages with

the sender and receiver having an address sharing the first three groups of numbers

are on the same network, and shouldnt be sent to another network. Thus knowing

where and how to send a message is the most important job of a router. Some simple

routers do this and nothing more. Other routers add additional functions to the jobs

they perform. Rules about where messages from inside a company may be sent and

from which companys messages are accepted can be applied to some routers. Others

may have rules that help minimize the damage from "denial of service" attacks. The

one constant is that modern networks, including the Internet, could not exist without

the router.

5.3) ETWORKIG-

Network is a data processing node that is interconnected for the purpose of

data interconnection. A network can be classified according to the various layers of

OSI. These layers are i) Physical ii) data iii) network iv) transport v) services vi)

presentation vii) application

5.31) PROTOCOL SADSTADARDS -

PROTOCOL-

Set of rules governing communication between network elements(e.g.

computers) defining:

1. syntax = what2. semantics = how3. timing = when (and how fast)

EED FOR STADARDS-

1-Over the past couple of decades many of the networks that were built used

different hardware and software implementations, as a result they were incompatible

and it became difficult for networks using different specifications to communicate

with each other.

2-To address the problem of networks being incompatible and unable to communicate

with each other, the International Organisation for Standardisation (ISO) researched

various network schemes.

3-The ISO recognised there was a need to create a NETWORK MODEL that would

help vendors creates interoperable network implementations.


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STADARDS-

1- Agree-upon rules enabling interoperability2- Thoroughly tested and adhered to.3- Established by standard organization:

a) International standards organization(ISO),b) International telecommunications union telecommunication standards

sector(ITU-T)

c) American National Standards Institute (ANSI)d) Institute of Electrical and Electronics Engineers(IEEE)e) Electronics Industries Association(EIA)

OSI REFERECE MODEL AD APPLICATIOS-

The model was developed by the International Organisation for

Standardisation (ISO) in 1984. It is now considered the primary Architectural model

for inter-computer communications. The Open Systems Interconnection (OSI)

reference model is a descriptive network scheme. It ensures greater compatibility and

interoperability between various types of network technologies.

Figure No.7( OSI layer)

The OSI model describes how information or data makes its way from application

programmes (such as spreadsheets) through a network medium (such as wire) to

another application programme located on another network. The OSI reference model

divides the problem of moving information between computers over a network

medium into SEVEN smaller and more manageable problems. This separation into

smaller more manageable functions is known as layering.


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LAYER 7: APPLICATIO-

The application layer is the OSI layer that is closest to the user .It provides

network services to the users applications. It differs from the other layers in that it

does not provide services to any other OSI layer, but rather, only to applications

outside the OSI model. Examples of such applications are spreadsheet programs,

word processing programs, and bank terminal programs. The application layer

establishes the availability of intended communication partners, synchronizes and

establishes agreement on procedures for error recovery and control of data integrity.

LAYER 6: PRESETATIO-

The presentation layer ensures that the information that the application layer

of one system sends out is readable by the application layer of another system. If

necessary, the presentation layer translates between multiple data formats by using a

common format provides encryption and compression of data. Examples- JPEG,

MPEG, ASCII, EBCDIC, HTML.

LAYER 5: SESSIO-

The session layer defines how to start, control and end conversations (called

sessions) between applications. This includes the control and management of multiple

bi-directional messages using dialogue control. It also synchronizes dialogue between

two hosts' presentation layers and manages their data exchange. The session layer

offers provisions for efficient data transfer. Examples- SQL, ASP.

LAYER 4: TRASPORT-

The transport layer regulates information flow to ensure end-to-end

connectivity between host applications reliably and accurately. The transport layer

segments data from the sending host's system and reassembles the data into a data

stream on the receiving host's system. The boundary between the transport layer and

the session layer can be thought of as the boundary between application protocols and

data-flow protocols. Whereas the application, presentation, and session layers are

concerned with application issues, the lower four layers are concerned with data

transport issues. Layer 4 protocols include TCP (Transmission Control Protocol) and

UDP (User Datagram Protocol).

LAYER 3: ETWORK-

It defines end-to-end delivery of packets. It defines logical addressing so thatany

endpoint can be identified. Defines how routing works and how routes are learned so

that the packets can be delivered. The network layer also defines how to fragment a


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packet into smaller packets to accommodate different media. Routers operate at Layer

3. Examples- IP, IPx.

LAYER 2: DATA LIK-

The data link layer provides access to the networking media and physical

transmission across the media and this enables the data to locate its intended

destination on a network. The data link layer provides reliable transit of data across a

physical link by using the Media Access Control (MAC) addresses .The data link

layer uses the MAC address to define hardware or data link address in order for

multiple stations to share the same medium and still uniquely identify each other.

Concerned with network topology, network access, error notification, ordered

delivery of frames, and flow control. Examples: - Ethernet, Frame Relay, FDDI.

LAYER 1 PHYSICAL LAYER-

The physical layer defines the electrical, mechanical, procedural, and

functional specifications for activating, maintaining, and deactivating the physical

link between communicating network systems. Physical layer specifications define

characteristics such as:

1. voltage levels2. timing of voltage changes3. physical data rates4. maximum transmission distances5. physical connectors

Physical layer implementations can be categorized as either LAN or WAN

specifications.

Figure No.8(layer switch)


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COECTIO-ORIETED AD COECTIOLESS

ETWORKSERVICES-

In general, transport protocols can be characterized as being either connection-

oriented or connectionless. Connection-oriented services must first establish a

connection with the desired service before passing any data. A connectionless service

can send the data without any need to establish a connection first. In general,

connection-oriented services provide some level of delivery guarantee, whereas

connectionless services do not. Connection-oriented service involves three phases:

connection establishment, data transfer, and connection termination. During

connection establishment, the end nodes may reserve resources for the connection.

The end nodes also may negotiate and establish certain criteria for the transfer, such

as a window size used in TCP connections. The data transfer phase occurs when the

actual data is transmitted over the connection. During data transfer, most connection-

oriented services will monitor for lost packets and handle resending them. The

protocol is generally also responsible for putting the packets in the right sequence

before passing the data up the protocol stack.

5.32) LA-

LAN is a high-speed data network that covers a relatively small geographicarea. It typically connects workstations, personal computers, printers, servers, and

other devices. LANs offer computer users many advantages, including shared accessto devices and applications, file exchange between connected users, and

communication between users via electronic mail and other applications.

LA TOPOLOGIES-

LAN topologies define the manner in which network devices are organized.

Three common LAN topologies exist: bus, ring, star.

A bus topology is a linear LAN architecture in which transmissions fromnetwork stations propagate the length of the medium and are received by all other

stations. This is illustrated in Figure.

Figure No. 9( bus topology)


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A ring topology is a LAN architecture that consists of a series of devices

connected to one another by unidirectional transmission links to form a single closed

loop. Both Token Ring/IEEE 802.5 and FDDI networks implement a ring topology.

Figure depicts a logical ring topology.

Figure No 10 (ring topology)

A star topology is a LAN architecture in which the endpoints on a network are

connected to a common central hub, or switch, by dedicated links. Logical bus and

ring topologies are often implemented physically in a star topology, which is

illustrated in Figure.

Figure No.11 (star topology)

5.33) WIDE AREA ETWORK (WA)-

This covers a relatively broad geographic area and that often uses transmission

facilities provided by the common carrier ,such as telephone companies .WAN

technologies generally function at lower three layers of OSI reference model ; the

physical layer ,the data link layer ,and the network layer.

5.34) BASIC HARDWARE COMPOETS

All networks are made of basic hardware building blocks to interconnect

networknodes, such as Network Interface cards (NICs), Bridges, Hubs, Switches, an


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routers.

a) ETWORK ITERFACE CARDS -A network card ,network adapter or NIC is a piece of computer hardware

designed to allow computers to communicate over a computer network .It provides

physical access to a networking medium and provides a low level addressing system

through the use of MAC address .It allows to connect to each other either by using

cables or wirelessly.

b) BRIDGES-

Figure No.12 (bridge)

a network bridge connects multiple network segments at the data link layer of

the OSI model .Bridges are similar to repeaters or network hubs ,devices that connect

network segment to the physical layer ,however a bridge works by using bridging

where traffic from one network is managed rather than simply rebroadcasted to adjust

network segments i.e. when data is given in form of packets it first amplifies it then it

broadcasts to various network segments.

c) HUBS-A hub is a piece of hardware which provides the connectivity of a segment of

a network by directing traffic through the network. It simply copies the data to all of

the nodes connected to the hub .Hubs are commonly used to connect segments of a

LAN. A hub contains multiple ports. When a packet arrives at one port, it is copied to

other ports so that all segments of the LAN can see all packets.


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Figure No.13 (hubs)

d)SWITCHES -These are the devices of the network that directs traffic to the correct node by

filtering and forwarding packets between nodes .Switches operate at the data linklayer and sometimes the network layer of the OSI reference model and therefore

support any packet protocol .Bridges uses MAC address table to direct but switches

uses IP address table therefore it works in the layer 3 of the OSI reference model

e) ROUTERS

Figure No. 14(router)

These are networking devices the forwards data packets along networks by using

header and forwarding tables to determine the best path to forward the packets.

They use protocols such as ICMP to communicate with each other .A router is

usually used to connect at least two network, commonly two LANs, or WANs, or a

LAN and its ISP network.

Routers are usually located at the gateways .the place where two or more network

connects.


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f) ETWORK MEDIA-There are various ways of connection

1. Copper wire -This wire are used in BNC cables, UTP CAT 5, 6, 7 cables etc

2. Optical fiber cable

3. Wireless technology

5.35) TPC KAHALGAO LOCAL AREA ETWORK-

In IT building NTPC WAN is connected to Cisco 2620 router and is hence

connected to E5Matrix ,two hubs ,and a 3com switch are connected with the help of

the UTP line .From IT building connection are made to central stores , administrative

building , CHP control and service building through optical fiber .In each of the

places such as service building ,central building etc connection are made via hubs

and switches .From CISF gate 1 a bridge is connected which is connected by a

telephone line to the bridges of various places such as MGR, EDC, Hospital and

Estate office.

The network with which kahalgaon is connected is star topology ie a hub

network. All the network of various NTPC stations is connected to EOC Noida. For

example Kahalgaon is connected to EOC Noida with the help of satellite. Here there

is a type b antenna of 7.5 m diameter. It is a parabolic dish. We have a multiplexer

which has multiple inputs such as LSD having frequency of 4kbps, HSD of 256 kbps

and voice signal of low frequency i.e. 3-4 kHz. These multiple inputs connected to

multiplexer gives a single output to the satellite modem which amplifies the signal to

frequency to intermediate frequency having frequency of 70 MHz.

Then it is connected to SPT whose function is to transmit and receive at radio

frequency i.e. at 6000 MHz the function of SPT is that transmits radio frequency to

LNA (Low Noise Amplifier) and SSPA (Solid state power amplifier).The output of

both LNA and SSPA are connected to the antenna. The same path is followed when

the signal is to be received. Demodulator and demultiplexer are acting in place of

modulator and multiplexer when the signal is to be received.

5.4) TELEPHOE EXCHAGE

In NTPC Kahalgaon all the telephones are connected to each other with the

help of telephone exchange called intercom. There are also so many function of

telephone exchange like it provide the broadband, CUG (closed user group)

connectivity.


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FEATURE OF EXCHAGE-

1. Connectivity of landline phones.2. Connectivity of CUG cells.3. ITDF integrated testing and diagnostic facility.4. Flexible number system.5. Caller identification system.6. 1 Port capacity for each exchange.7. Provision of various class of service.8. Facility for creating massage.9. Malicious call tare

PRESET STATUS-

Exchange location working intercom.

1. CORAL-PLANT 4962. CORAL.PTS 6103. HICOM-PLANT 430

It used for controlling the entire system. Two types of cards are used in exchange.

a. MCC- master control cardb. PSC-peripheral shelf controller.The MCC is the main CPU of the system, which houses the CPU, memories, PCM

switches and other control logic. The PSC is used for interfacing the peripheral shelf

to the main shelf. The peripherals cards are used for connecting to subscribe lines and

trunk lines. Some PSCs are FLC32 (feature line cards, DCC 16(DIGITAL

COMMUNICATION CARD. The training and switching ckt ate present in the control

cards. The main processor is housed in master control cards. The data base of entire

system is stored in the memory devices in the MCC .

6-COTROL AD ISTRUMETATIO

Thermal power stations employ a great number of equipment performing

number of complex process, the ultimate aim being the conversion of chemical energy

into electricity .In order to have stable generating conditions, always a balance is

maintained that Heat input =Electricity output +losses .But this balance is frequently

disturbed .When this balance is disturbed al the process variables deviate from their

normal values thus creating the necessity for the following:-

(i)Instruments: To measure and indicate the amount of deviations


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(ii)Automatic control: To correct the deviations and bring back to normalcy

(iii)Annunciation: To warn about the excessive deviation if any.

(iv)Protection: To isolate the equipment or process from dangerous operating

condition caused to such excessive deviation

TYPE OF ISTRUMETS-

Instruments to measure the physical quantities such as temperature, pressure,

level flow etc. The other type instruments are the electrical measuring electrical

quantities such as current, voltage etc. Different type of instruments normally in use

is given below.

IDICATORS-

Indicators are of two categories local and remote. Local indicators are self

contained and self operative and are mounted on the site .The remote indicators are

used for telemetering purposes and mounted in the centralized control room and

control panel.

RECORDERS-

Recorders can be of single point measuring a single parameters or multipoint

measuring a number of parameters by a single instrument

POWER STATIO ISTRUMETATIO-

Following are the instruments:-

6.1) TEMPERATURE MEASURIG ISTRUMETS -

The measurement ranges from ambient temperature viz. of air at inlet to F.C

fan to 1300C to 1400C inside the furnace zone .

Temperature measurement is to made from many media such as water, steam,

oil, (fuel oil and lubricating oil), air, flue gas, hydrogen gas, metal temperature of

bearing, turbine top and bottom, generating winding and cores, S.H tube metal etc.

filled system thermometry such as mercury in glass, in steel, vapors filled or gas filled

are used for local indication.

Bimetallic thermometers are also used for local indication .The selection of

thermometer depends on the range of temperature used .Resistance thermometers are

of platinum and copper resistance type .These are generally used up to 300C.

Above 300C thermocouples are used as primary sensors .The common type of

thermocouples used in thermal power stations are chrome-alum or chromel-coper

depending on the temperature.


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6.11) EXPASIO THERMOMETERS-

SOLID ROD THERMOMETERS-

A temperature sensing-controlling device may be designed incorporating in its

construction the principle that some metals expand more than others for the same

temperature range. Such a device is the thermostat used with water heaters.

6.12) ROD TYPE THERMOSTAT-

THE BI- METALLIC STRIP-

Bimetal strips are composed of two metals, as the name implies, whose

coefficients of linear expansion are dissimilar. These two metal plates are welded

together as a sandwich. When heated, both metals expand, but the metal with greatest

coefficient of linear expansion will expand more causing the sandwich to curl up or

down depending on the position of this metal.LIQUID I GLASS THERMOMETERS-

The coefficient of cubical expansion of mercury is about eight time greater

that of glass. Therefore, a glass container holding mercury, when heated, will expand

for less than the mercury it contains. At a high temperature the mercury will occupy a

greater fraction of the volume of the container than it will at a low temperature.

Figure No.15 (bourdon tube thermometer)

Under normal atmospheric conditions mercury normally boils at a temperature

of (347oC). to extend the range of a mercury in glass thermometer beyond this point

the top end of a thermometer bore opens into a bulb which is many times larger in

capacity than the bore. This bulb plus the bore above the mercury, is them filled with


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nitrogen or carbon dioxide gas at a sufficiently high pressure to prevent biiling at the

highest temperature to which the thermometer may be used.

Types of Hg in steel thermometers are-

1- Bourdon tube- the most common and simplest type2- Spiral type- more sensitive and used where compactness is necessary3- Helical type- most sensitive and compact. Pointer may be mounted direct on

end of helix.

THERMOMETER BULBS-

The thermometer bulb may take many forms dependent on the application. For

example, if the temperature of a large enclosure is to be measure the bulb may be in

the form of a U or of a considerable length of small tube into a spiral. This type of

bulb presents the surface area necessary for measuring the temperature of a gas and is

therefore used in this application.

1.Plane Bulb 2.Union Bulb 3. Pocket bulb 4. Wall Mounting 5. Long coil etc.

6.13RICIPLE OF THERMOELPECTRIC EFFECT-

SEEBECK discovered in 1821 that when a junction of Bismuth and copper

was heated an .e.m.f. was produced. The direction of the current was from the

Bismuth to the copper.

Figure No. 16(SEEBECK effect)

This discovery led to the later development of the thermocouple, a suitable

combination of two materials capable of producing an e.m.f the magnitude of which is

related to temperature. The range covered are from a few degrees absolute to 30000C.

Seebeck produced a list of materials the order of which is important. An extract from

the list is given below:


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Type Materials used Approx temp. range(oC)

B Platinum/Rhodium 50 to 1800

E Chromel/Constantan -40 to +750

J Chromel/Alumel -200 to 1200

R Platinum/ Rhodium up to 1600

S Platinum/Rhodium up to 1600

RESISTACE TYPE THERMOMETERS-

The other main system used to measure temperature relies on the fact that as a

wire is heated its electrical resistance increases in proportion to the temperature. We

must, therefore, find a method to measure a changing resistance and display this on a

recorder or indicator. The rapid variation of resistance with temperature certain

semiconductors are employed in the thermally sensitive resistor or thermostat to

measure temperature.

Figure No. 17(resistance thermometer)

Figure No.18 (acoustic pyrometer)


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ACOUSTIC PYROMETER-

It is Used for high temperature measurement in furnace. The velocity of sound

in a medium is proportional to the temperature. Transmitters are placed on one side

and receivers are placed on other side.

6.2) PRESSURE MEASUREMET-

For local indication of pressure and differential pressure ,bourdon tube and

diaphragm type gauges or liquid manometers are used .Remote measurement of

pressure is done by transmitters either electric/electronic or pneumatic coupled with a

secondary instrument indicator /recorder .

PRESSORE MEASURIG DEVICES-

The common pressure measuring devices are:-

1. Manometers using water ,mercury and other liquids of known density for

low pressure measurement

2. Diaphragms, Capsule bellows for measuring medium pressure

3. Bourdon tube gauges for measuring medium and high pressure

4. Transducers of different types for measuring pressures of all ranges for

telemetering purposes.

MAOMETERS-

U -TUBE MAOMETER

P2-P1 =HPG where p is the density of the manometer liquid G is

acceleration due to gravity. If P2 is the pressure applied and P1 is the pressure applied

then the differential pressure working on the fluid is P2-P1 which will raise the

Column of fluid in the low pressure limb to a height H from the new surface of

separation.

ICLIED TUBE MAOMETER -

Figure No.19 (u-tube manometer)


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It gives increased length of column for less differential pressure. Manometers are

available with adjustable inclination depending upon the range required.

DIAPHRGAM, CAPSULES AD BELLOWS

The present day low pressure to medium pressure applications are with

diaphragms. The simplest form of these elements is the single diaphragm instrument.

In this a thin flat plate of circular shape is fixed firmly round the edges .On applying

pressure to one side greater than the one existing on the other the diaphragm deflects

away from the high pressure side the maximum deflection occurring at the centre.

CORRUGATED DIAPHRAM-

By introducing corrugation in the circular diagram the deflection pressure

relationship is maintained for larger movement. Here the deflection is related to

a) The radius of the diagram

b) The radius of each corrugation

c) The depth of corrugation

d) The thickness of material

CAPSULES-

Further improvement of deflection was achieved by forming a capsule out of

two circular diaphragms jointed at the edges

BELLOWS-

A thin walled tube is taken and formed into corrugated shapes by special hydraulic

pressure .The corrugations are called convolutions. The flexibility of the bellow

depend upon

i)The number of convolutions.

ii) The square of the outside diameter of the bellow.

iii) The cube of the wall thickness.

iv) Youngs modulus of elasticity.

BOURDO TUBE GAUGES -

This is the oldest instrument initially to measure pressure from medium to

high ranges .It consists of a metal tube almost elliptical in cross section formed into a

C shape, a long spiral or to flat spiral by special machines, one end of the tube is

closed and sealed and the opposite end is left open and terminated to a block where

the process pressure is applied.


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Figure No. 20( bourdon tube pressure gauge)

If the pressure inside the tube is more than that existing outside , the elliptical

section changes its shape an begins to straighten out ,with the result the free end

deflects in a arc. The deflection is proportional to the pressure difference between

inside and outside pressure .There are other factor affecting the deflection .The usable

part of the movement of the C shape bourdon is of the order of 3mm or 6mm length

of arc in order to make this small movement a measurable amount, some sort of

multiplying mechanism is introduced between the tube and indicating points .Most

commonly used mechanism is sector and pinion movement.

6.3) LEVEL MEASUREMET-

In power station application level can be defined as the height of the liquid or

solid media above or below a reference line usually the base .Levels, below the

reference line may also be required in dynamic condition such as boiler drum etc.

If the dimension of a vessel is known then the volume or mass of its contents can be

determined by measuring the level.

LEVEL MEASUREMET-METHODS-

There are many methods of measuring level the selection of particular system

is largely determined by practical considerations

The methods to be considered can be classified as follows-

1) Direct dipping

2) Direct viewing

3) Floats and liquid displacers

4) Head pressure measurement

6) Ultrasonic

7) Nucleonic


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DIRECT DIPPIG METHODS-

1) DIPSTICKS-

It is simply a calibrated scale inserted into the liquid until the zero of the scale

hits the bottom of the tank, the level is read directly of the scale

2) HOOK GAUGE-

There is difficulty in measuring of the dipstick reading due to parallax. In this

case a hook gauge type is used .It consists simply of a wire cord of corrosion resisting

alloy such as gun metal or stainless steel, bent into U shape with one arm longer

than the other

DIRECT VIEWIG-

(1)SIGHT GLASS-

The sight glass is very useful as a simple arrangement wherein a section of

liquid is brought outside the vessel and displayed alongside the main scale. If the

diameter of the bore of the slight glass is t small enough to introduce small error due

to capillary action the liquid will stand at the same level in the slight glass and the

vessel provided the top of the slight glass is subjected to the same pressure he top of

the vessel The system analogous a U tube manometer .slight glasses are usually

installed with two isolating valves and a blow down valve for clearing purposes .In

high pressure as a boiler drum the gauge is usually fitted with a automatic cut off that

if the slight glass breaks the danger of any one getting injured becomes less

(2)WATER GAUGE CLOSED CIRCUIT TELEVISIO REMOTE DISPLAY-

A CCTV monitor is mounted a few feet away from the gauge and is carefully aligned

with the light path through it .The CCTV monitor is located in the control room .This

system is difficult to operate with high steam pressure.

6.4) FLOW MEASUREMET-

Fluid flow in industrial undertakings occur in two general forms either as a

flow in pipe of conduit or in case of liquid only as a flow in open channel .In

both the cases type rate of flow is of primary importance and in large number of

plants the totalized flow over a specific period is required in addition

RATE OF FLOW MEASURIG ISTRUMETS-

This may be broadly divided into -

a)differential pressure flow meters :-


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i) Orifice pattern.

ii) Venturi and nozzle pattern.

iii) Pilot tube pattern.

iv) Dall tube pattern.

b) Variable area flow meters.

c) Displacement and inferential flow meters.

d) Electromagnetic flow meters .

e) Ultrasonic flow meters .

ORIFICE PATTER-

Figure No.21 (orifice flow meter)DIFFERETIAL PRESSURE FLOWMETERS-

It uses the principle of Bernoullis theorem.

COCETRIC ORIFICE PLATE-

This involves a circular metal plate with a central hole or orifice concentric

with the circumference of the plate. It is fixed between the pipe flanges and is located

by the flange bolts. The orifice is then concentric with the internal bore of the pipe.

VETURI TUBE-

There are virtually three sections of the tube ; the inlet or the upstream cone

,the throat ,and the outlet or downstream cone .Pressure tapings are taken at the inlet

entrance of the cone , and at the throat.

OZZLES-

The nozzle fall between the venture tube and the orifice plate as a means of flow


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measurement.It approximates to a Venturi tube with a curved form of approach,

giving a gradual change of sectional area and has the same order of discharge

coefficient.

Figure No22 (nozzle)


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REFERECES

1. U#3, manual of KhSTPP 4201MW.2. U# 5, literature and Report, KhSTPP.3.

Driplex CPU manual for KhSTPP 3X500 MW.

4. Technical Diary, 500 MW KhSTPP.5. Steam Turbine description, BHEL manual for 500 MW Power

Plant.

6. IT department of KhSTTP.7. Modern Power Station Practice, Third Edition, CEGB, Vol. E.

javed nt pc project

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