A SIX WEEK INDUSTRIAL TRAINING REPORT ON

BHARAT HEAVY ELECTRICAL LTD HARIDWAR Submitted for partial fulfillment of award of

BACHELOR OF TECHNOLOGY

Degree in

ELECTRONICS AND COMMUNICATION ENGG

Under the Guidance of

VIKAS SINGLA (senior Engineer, BHEL)

RAJ KUMAR GOEL INSTITUTE OF TECHNOLOGYGHAZIABAD

SUBMITTED TO SUBMITTED BY

Mr. ABHINAV BANSAL MANISH KUMAR PANDEY ROLL NO. - 1003331054 ( ECE DEPARTMENT) ECE 7TH SEM SEC - A

ABSTRACT

I had done my training in BHEL in Telecommunication area . In this field I learnt about telephony and its types, electronics Exchange and cards used in exchange, types of tone used in telephony , how a call is made , types of connection used i.e through cabling or through wireless connection, facility provided by exchange in telephone. BHEL is the largest engineering and manufacturing enterprise in India in the energy related infrastructure sector today and one of the MAHARATNA company. The wide network of BHEL's 14 manufacturing division, four power Sector regional centers, over 150 project sites, eight service centers and 18 regional offices, enables the Company to promptly serve its customers and provide them with suitable products, systems and services – efficiently and at competitive prices. Product of BHEL are boiler , Gas generator, hydro generator ,Steam turbines, gas turbines , Hydro turbines, AC motors ,Transformers, Wind mill, Valves, Electrostatics precipators etc. The financial turnover during the year 2007-08 was 21,401 crores rupees and current in 2012-13 turnover is 1,20,000 crores rupees.I express my sincere thanks and gratitude to BHEL authorities for allowing me to undergo the training in this prestigious organization. I will always remain indebted to them for their constant interest and excellent guidance in my training work, moreover for providing me with an opportunity to work and gain experience.

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CERTIFICATE

This is to certify that MANISH KUMAR PANDEY hisundergone six week training here in our organization BharatHeavy Electrical Limited, Haridwar (UK). His discipline andperformance during the training period was excellent. We wish hima very prosperous and bright career in future.

(VIKASH SINGLA) (V.K. JOSHI) Sr. Engineer Sr. Technician

(WEX-TELECOM) (WEX-TELECOM)

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ACKNOWLEDGEMENTS

I am extremely thankful and pay gratitude to Mr. Puneet Srivastva(HOD , ECE Department,rkgit) sir for giving me opportunity for training . I would like to thank my respected parents, who always encouraged me and taught me to thinkand workout innovatively what so ever be the field of life. My sincere thanks goes to Mr.Vikash singla (Sr. Engineer) Telecom for his prodigious guidance, persuasion, andpainstaking attitude, reformative and prudential suggestion throughout my summer trainingschedule.

Special thanks go to Mr.V.K.Joshi (Sr.Technician) Telecom. Who helped me a lot ingiving minute details of Telecom. Department and enlightened me with the knowledge ofExchange equipments and their working.

Last but not the least, my sincere thanks to all the staff members and friends for instilling in mea sense of self-confidence.

NAME: MANISH KUMAR PANDEY

BRANCH: (ELECTRONICS & COMM. ENGG.)

Academic Year: 2010-2014

Institute: RAJ KUMAR GOEL INSTITUTE OFTECHNOLOGY

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INTRODUCTION ABOUT B.H.E.L.

TELECOMMUNICATION SYSTEM IN BHEL, HARDWAR.

VOCATION TRAINING REPORT: 2014

CONTENTS

1. Introduction.

2. The Organization.

3. Telecommunications.

4. Electronic Exchange(s).

5. Telephone Lines.

6. Connection Types.

7. General faults occurring in an Exchange.

8. Special User Features of Various Exchanges.

9. Optical Fiber System.

10. Maintenance.

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1. INTRODUCTION.

In past few years the field of communication has been developing with no leaps or bounds. Ithas become a necessity of each human being to be connected with each other. Telephone israpidly becoming a tool to quench this thirst.

In Automatic Telephony, operators are not required to establish connections manually betweenthe different calling and the called subscribers as are required in the case of manual telephonesystems. In these system subscribers those selves establish required connections by operatingthe different switches placed at the central place known as the EXCHANGE from theirtelephones at remote place from it. The automatic telephone systems are rapidly replacingmanual ones due to their outstanding merits over the latter types, some of which areenumerated below:

* In Automatic Telephony higher level of secrecy is maintained due to absence of Operators who can overhear the conversation if they like in the manual telephone Systems. The working of an Automatic Telephone system does not depend for its efficiency On the personal efficiencies of the operators.

* There is no possibility of the calls being missed or wrong metering being done due to faultsof operators or due to phonetic errors between the subscribers and the operators.

As no operator is required, the running cost of the exchange is reduced.

COMMUNICATION Dia.I

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2. THE ORGANIZATION.

BHEL was primarily set up to meet the needs of the power sector in the country. Thefirst plant was established nearly 35 years ago at Bhopal, which heralded the genesis of theheavy electrical equipment in India. BHEL is today the largest engineering enterprise in India,with excellent track record of performance, making profits continuously since 1971-72. Itachieved a sales turnover of Rs. 3154 carores with a pretax Profit of Rs.201 carores, in 1990-91.

The areas of BHEL operations broadly cover conversion, transmission, utilization andconservation of energy in core sectors of the economy like Power, Industry and Transportation,etc., and fulfill vital infrastructure needs of the country.

Today, BHEL has 13 manufacturing divisions, 8 service centers and 4 Power SectorRegional Centers, in addition to over 150 project sites spread all over India and even abroad toprovide prompt and effective service to customers.

BHEL Hardwar is one of the premier organizations which is honored by I.S.O.-9002specifications.

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3. TELECOMMUNICATION.

BHEL manufactures EPABX and MAX systems based on C-Dot technology and hasplans to make other ranges of telecommunication equipment also.

These are basically used for connecting links between various modules like peripherals,exchange and its equipments. It is necessary to run a number of internal cables of suitableconductors between the following stages and frames:-

1. Handset to exchange's cable chamber2. Cable chamber to M.D.F.3. M.D.F. to I.D.F.4. I.D.F. to Number Block5. Number Block to Exchange Equipment6. Between two exchanges7. Between two cities8. Between two countries

Prior to advent of Electronic Exchanges inter-connection of various circuits are made bymechanical contacts that are operated by mechanical movements produced by the attraction ofan iron armature of an electromagnet or by the operation of an electric motor. There are somedisadvantages of such systems for using mechanical contacts, due to following reasons: Contacts are subjected to wear and tear. Require adjustments time to time. Maintenance is highly precise. Prone to corrosion. Etc...

But now-a-days Electronic Exchanges are used. In Electronic exchange electronic deviceseffect the inter-connection between different transmission circuits and Electro-mechanicalrelays and switches are dispensed with. Such electronic devices remove difficulties associatedwith mechanical contacts. The greatest advantage of using electronic devices in place ofelectromechanical devices is that no time is loosed in making a connection and a very highspeed of operation is possible.

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4. ELECTRONIC EXCHANGES.

Electronic Exchanges are of two types:1. Tone type2. Pulse type

1. Tone type : In this type of exchange sine waves are used. There speed of dialing for a givennumber is more than that of Pulse type.

2. Pulse type : In this type of exchange square wave is used due to which the dialing speed islesser. The telephone apparatus used for both types are different in construction. But now daysboth types of apparatus are integrated in a single machine in which switch-over can be madevia a selector switch.

TONES USED IN MODERN TELEPHONY

Dial Tone : When handset is picked up from the cradle, then Dial tone is heard if a free lineis available. This means that the instrument is ready to send the signals to the exchange. Whenthe subscriber takes up the receiver then signals are sent M.D.F. then to I.D.F., line Numberblock and to Peripherals where in various line-cards are mounted in a shelf. Whencorresponding number on the line-card is free then the Ringer section of that Peripheralgenerates a signal called tone. This tone is a continuous burble sound of 400 Hz. modulated by25Hz. and is sent to the calling subscriber as soon as his line seizes the free line. The subscribermust not dial before receiving this tone; otherwise he is liable to get wrong connection. If hedoes not get this tone, he should try after some time.

Busy Tone : When the called subscriber is engaged with other call, this tone is heard. It consistsof a sound of 400 Hz. which is regularly interrupted at equal intervals. It is generally on for0.75 sec. and off for also 0.75 sec.

Ringing Tone : When a number is dialed then telephone of the called subscriber starts ringing.Calling subscriber should get this information and this is indicated by sending ringing tone ofinterrupted 400 Hz. supplies modulated by 25 Hz. and its durations are generally equal to theduration of ringing current, which rings the bell. It may be 0.4 sec. on, 0.2 sec. off , 0.4 sec. onand 2 sec. off and so on or it may be 0.75 sec. on and 0.75 sec. Off and so on. When thisringing tone is received, the calling subscriber knows that the connection is completed and thatthe bell of the called subscriber is ringing.

Number Unobtainable Tone: This tone is sent when the number dialed cannot be obtained. Ifany subscriber dials which is not actually connected to the exchange, this indication is send.This is also a tone of 400 Hz. with interruption of 200 msec. every 3 sec.

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Now-a-days push button type telephone apparatus are used. This apparatus can be explodedinto following sections:

1. Ringer section 2. Speech section (Transmitter and Receiver section)

3. Voltage limiter section

From telephone exchange two wires or connectors run for each number, in which one is neutraland the other is main or positive. For the telephone circuit to work the necessary supply isprovided by the exchange. Like other circuits telephone also operates when a circuit isestablished between calling and called subscriber. When one dials a number then thecorresponding relays at the exchange established a circuit automatically. The telephoneexchange supplies 40-60 volt D.C. and 110/20 Hz. to operate this circuit. This is requiredbecause of voltage drop that may creep in long transmission wires. As soon as the handset ispicked-up this 48-volt D.C. supply is available at voltage limiter section, dialing pulsegenerator and speech section.

In telephone dialing two types of frequencies are used which are:* High band tone (1216 Hz. to 1645 Hz.)* Low band tone (701 Hz. to 936 Hz.)

Frequencies used in TelephonyThe numbers from 1 to 5 falls in low band and 6 to 9, 0 falls in high band. Till the handset ison-hook, the ringing section of the apparatus is on through telephone line but on lifting thehandset the ringing section becomes off, also the dialing and speech section becomes ready. Onlifting the handset first the dial tone is received which is amplified by the amplifier of speechsection.When a number is pressed on the keyboard, the dialing pulses are made on and off according tothe number dialed. For example if 5 is pressed then dialing pulses are made on and off 5 times.This process can be heard on the receiver. There is a gap of 1 sec. between consecutivelypressed numbers.When the handset is placed on or is lifted from the instrument a switch is operated called thehook-switch. The main function of this switch is to toggle between telephone-line and ringer,dialing & speech sections of the telephone. When the handset is on the telephone then ringersection of the telephone is on while on lifting it ringer section is disconnected and dialingsection is connected.

How the telephone call is made:

Telephone call is characterized into two sections:1. Outgoing calls : Generally a voltage of 48V-60V D.C. always remains on the telephone linebut as the handset is picked-up the voltage limiter drops this voltage to 9-12V. On hearing thedial tone it is confirmed that the apparatus is ready to work and after dialing the number aringing pulse is send to the called party. When the calling party picks-up the handset the billingmeter of the exchange becomes activated. There is a counter in the exchange, which counts thepulse and converts them into calls.

2. Incoming calls : These are just opposite of outgoing calls. In the incoming calls thetelephone detects the ringing signal from the exchange and provides the ring. At the instance ofringing signal, there remains a voltage of 75-110V./20 Hz. on the telephone. A high voltage(A.C.) is sent from the ringer section of the exchange to start the ringer circuit of the telephone.When the ringing signal is received it should be properly isolated as it may give a shock. Thisringing circuit is on until the handset is not picked-up at the called party. The duration of thistone, if unattended, is 1 minute after which an engage tone is heard. After lifting the handset acircuit is established and a call is made.

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Electronic Exchange Dig.II

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There are various powers providing circuits available in the exchange to run the circuitry.These are broadly categorized in two categories: * Outside the exchange* Inside the exchange

Outside the Exchange :

Since the voltage supplied in Indian Subcontinent is 220-volts/50 Hz. A.C. but for the normalworking of the exchange 48(46-53) volts of D.C. is required.

Hence a Rectifier circuit, backed with battery array for power-failures, is used. Thisrectifier block not only rectifies the input supply but also works as a battery charger. It isknown as Float rectifier cum charger.

Battery backup is utilized for smooth operation of the exchange during power failures. Forbattery back-up lead acid battery array is used in parallel to the supply from the rectifier block,so that during power failures the exchange supplies are not terminated.

Inside the Exchange:

Inside the telephone exchange various types of power supplies are used for powering variousmodules (for example: - Line-cards, Ringer). Some of them are: -

# -5 V. 12 A # +5 V. 12 A

# +12 V. 6A.

From M.D.F. a number of cables, based upon the requirement of a place, are connected tocabinets. On the cabinets these cables are divided into cables of 20 pairs. Now every 20 paircable goes to the distribution box (D.B.). At the D.B. this 20 pair cable is further divided intotwo parts of 10 pairs each. These pairs are then connected to the subscriber ports via jumpers.The line from these ports then goes to the subscribers through single pair cables which areusually of P.V.C. type. These wires are connected to the instrument via Rosette-Box.

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M.D.F.: -This frame serves the following purposes: -

It is place where both external and internal cables are terminated. The external individualscable carry conductors from subscribers who are necessarily from the same locality and assuch their numbers cannot be in numerical order. On the other hand, the internal cableconductors come from apparatus side in numerical order. This cross-section between thetwo cables is done on the M.D.F. through jumper wires.

It carries all the protectors used in the exchange. The different protectors that are used are(a) Fuses, (b) Heat coils, and (c) lightning protectors.

This M.D.F. is an ideal place for testing purpose. Both the internal and the external cablesare available at this frame and, therefore, both external and internal wiring and lines can betested for this purpose.

I.D.F.: -These frames like M.D.F. consists of a large number of verticals with horizontal cross-

arms fitted with tag blocks at both the ends. The cable from M.D.F. is terminated on themultiple sides from where connections are extended to metering and from the exchange sidecables are run to the respected line-cards. The two tag blocks are joined by means of jumperwires as in the M.D.F., so that any subscriber can be given connection to any uniselector on theline-card. The subscriber and, therefore, their uniselector are divided into different groups andit is necessary for these groups to originate more or less the same amount of traffic for smoothdistribution among different trunks.

CARDS :- In an electronic exchange a no of cards are used some of these are named below. These

cards are-z-24 ANALOG EXTENSION CARDua 32 DIGITAL EXTENSION CARDatr 2 DIT CARD USED THROUGH PROPER LINEnddi ANALOG TRUNK CARD USED AS JUNCTION TO JUNCTIONcpu3 CENTRAL PROCESSING UNITintof INTERFACE CARDmmsfd FLOPPY DRIVE USED BY OWNERsuvg VOICE CARD(ex. No is busy try after some time)idtl8 LOOP DAILINGpcm2 DIGITAL TRUNK CARD USED THRUGH OFCgpa-1 CONFRENCE CALL

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These cards serve allthe essential works of a telephone connection.

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NEW MDF Dig.III

OLD MDF Dig.IV

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5. TELEPHONE LINES.

In BHEL-Hardwar three types of telephone lines are used. They are: - MAX Lines EPABX Lines C-DOT Lines

MAX Lines:

Before MAX Ex. Lines are used only Internal Exchange. But New (CORAL) MAXlines are used for both internal (Intercom) and external communication links BHEL.

EPABX Lines :EPABX lines are used for both internal and external communication links in BHEL. If

the user wants to dial outside the periphery of BHEL, he can use these lines. There are about500 lines available here. These lines are distributed in 17 line-cards with 24 line numbers ineach. Its I.D.F. section has 40 tag blocks. 96 numbers available here are connected via digitallines in which a host of facilities are provided that can be accessed using code 69.

C-DOT Lines :These lines are the direct telephone lines from C-DOT The facility they provide is

called DID (Direct Inward Dialing). It has 24 lines and any BHEL number starting with digit 5can be accessed using code 48.

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6. CONNECTION TYPES.

Types of Connections:* With wires i.e. Cables* Wireless Microwave Links through Satellite

Cables : Two types of Cables are used. They are:

1) Underground cables: These types of cables run under the earth and are basically used toconnect the exchange to the subscriber's Distribution Box (D.B.). They are further of two typesbased upon their construction and the insulating material used.

a. Paper core A.T.C. (Armored Tin Cable) b. Jelly filled A.T.C. (Armored Tin Cable)

2) Overhead cables: These types of cables are used to connect the equipments inside theexchange and to connect the peripheral devices to the subscriber's Distribution Box (DB) They are generally of P.V.C. type.

In an exchange, based upon the number of conductor pairs, following types of cables are used:* Single Pair cable* 2 Pairs cable* 5 Pairs cable* 10 Pairs cable* 20 Pairs cable* 50 Pairs cable* 100 Pairs cable

Color-coding:TYPE OF CABLECOLOR OF WIRES

Single pair Blue-White

2 Pair cable Blue-White/Orange-White

5 Pair cable Blue-White/Orange-White/Green-White/Brown-White/Grey-White

10 Pair cable Blue-White/Orange-White/Green-White/Brown-White/ Grey-White/Blue-Red/Orange-Red/Green-Red/Brown-Red/Grey-Red

20 Pair cable Blue-White/Orange-White/Green-White/Brown-White/Gray-White/Blue- White-Blue/Orange-White-Blue/Green-White-Blue/Brown-White-Blue/Gray-White-Blue/Blue-White-Orange/Orange-White-Orange/Green-White-Orange/Brown-White-Orange/Gray-White-Orange/Blue-White-Green/ Orange-White-Green/ Green-White-Green/Brown-White-Green/Gray-White-Green.

For 100 pairs cable the color-coding is same as that of the above 20 pairs cable except That the mate color is changed after each bunch of 20 pairs.

PAIRMATE COLOR1st 20 pairs White2nd 20 pairsYellow3rd 20 pairsBlack4th 20pairsViolet5th 20 pairs Red

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7. General faults occurring in an Exchange.

There are mainly two types of faults that often occur in the Exchange. These are basically* Faults that occur from Line* Faults that occur due to Instrument

A. Faults that occur from Line:

Due to line three types of faults may occur. They are categorized as under:

1. Break fault: They are also called as Disconnection faults. They can occur in the connectorsat home, in line or in exchange. In common they are broadly called as "Telephone is dead".

2. Loop fault: They are also called as Line-Shorting faults. In this fault connectors are shortedprior the instrument forming a local loop. If unattended for a long time they may cause severedamage to the Exchange.

3. Earth fault: This fault may occur due to:* wetting of connectors* Water in Rosette-Box* Weak insulation or* Oxidation of copper wireConnectors can either touch from earth, with other connector or with any conductor (such asmetallic table, frame etc.)

Problems that can occur due to line faults:1. Subscriber can not dial a number.2. Ring Trip i.e. connection from the exchange breaks after one ring.3. False Ring 4. Low speech5. One sided speech

Faults that occur due to instrument:These may be:* The number is not being dialed* One way speechReceiver coil is faulty

Faults that occur due to instrument: cont’d

* Plunger or Push switch faulty. Dial tone breaks after two or three rings. From second subscriber bell is heard to be going but at first subscriber only dial tone Is heard.* Instrument circuitry faulty. When loop or earth fault is received than exchange can be affected so it is wedged as soon aspossible because if not wedge for longer it can damage line-card too.

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To sense these faults first line-side is checked and then exchange side is checked atexchange. If however exchange side is correct then line faults after detection are handed over tothe concerned lineman for further checking.

8. LIST OF SPECIAL USER FEATURES ON VARIOUS EXCHANGES. A) MAX (CORAL INDIA PVT.LTD.NOIDA) Manufacturer: - JEUMONT SCHINEDIER, FRANCE Capacity: - 2700 lines

CALL PICK UP: 89-xxxx to pick up a call ringing at another locationxxxx.

CALL TRANSFER: 2 Parties conversing, any party can dial 3rd party, thenconversion among them Hang –up . The party on line now talk to 3rd party

PARTY CONFERENCE: While speaking with a party: a). (From Pulse Instrument: -- If CALLER requires dialing 3rdparty b). During conversation and maintaining talks, then dial 4. (From Tone Instrument: -- If CALLER requires dialing 3rdparty c). During conversation and maintaining talks, then flash, anddial 4.

MALICIOUS CALL TRACE: Dial 29 during conversation, to trace amalicious call From a MAX Extension. Then enquire from 4999 or 4424.

APPOINTMENT REMINDER: Dial 80-xx-yy {xx=hr, yy=min}. To Cancel: Dial 27.

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B) EPABX=ALCATEL 4400 Manufacturer: - ALCATEL, FRANCE Capacity: - 500 lines (96 DIGITAL, 404 ANALOG) Technology used: - P.C.M. - T.D.M.

1. TONE MODE DIAL: Dial # before no.{If instrument is not tone enabled ) 2. CALL TRANSFER: Hook FLASH: Do Hook Flash - On hearing prompt "Please dial." Dial the no., wait for party to respond, then Disconnect.

3. ENQUIRY CALL: FLASH (from Tone mode instrument.) or 2 (from Pulse mode) During converse’s, to put the party on HOLD. Then, dial a 3rd party and speak.

4. BROKER CALL: (After ENQUIRY CALL): Dial 1 To go BACK & FORTH, between two parties (one party in conversation & other On HOLD)

5. CONFERENCE-3 PARTY: While talking to 1st party, first make ENQUIRY CALL (Put on hold){FLASH from Tone; or 2 from Pulse}. Then - Dial 3rd party - Flash-- Dial 3.

6. AUTO CALLBACK: Dial 5 to book auto-callback when a busy PABX hangs up. ( To cancel auto-callback request: Dial 67 or/and 848)

7. PASSWORD MODIFICATION: 847-0000-xxxx (0000=old password; xxxx = new Password). This facility is available on STD enabled extensions only.

8. LAST CALLER CALLBACK: 851 {to ring the last unattended PABX Caller}

9. APPOINTMENT REMINDER: 852 then dial the time as {xx (hr) xx (min)} To cancel: 853

10. LAST NO. REDIAL: 854 User can use this if instrument. Doesn’t have a Redial Button.

11. CALL PICKUP: 72 - XXXX to pickup a call ringing at another extension.

12. CALL-PARK / RETRIEVE: It is used during an incoming or outgoing call, to speak From a different set. (To park from own (speaking) set: FLASH-855- dial own extension number. Then "Hang-up". The call is now parked, and the other party is kept on hold. (To pick up from a different set: 855- dial own extension number) (To pick up from own set (later, if not taken elsewhere) 855)

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9. OPTICAL FIBER SYSTEM.

Fiber optical transmission medium is fast emerging as an alternative and strongcompetitor to coaxial cables in telecommunication networks.

Long distance data transmission in electrical cables suffers from ground loop problems.The merits of the optical fiber stem from the fact tat the basic material used in theirconstruction is nonmetallic and electrically non conductive.

In contrast, the nonmetallic and totally dielectric fiber optical cable are immune to radio

frequency an other electromagnetic interferences. Ground loop and common mode voltageproblem do not exist and data can be transmitted between points of vastly different potential. Inoptical cables the information is transmitted by packets of photons which have no charge.There is no possibility of sparks or short circuit when a fiber is cut. The bandwidth highcompared to that of the electrical cables. The standard RG-58 coaxial cable has bandwidthdistance product of a typical optical fiber is about 100 MHz-Km.

Fiber cables are about the thickness of a human hair any dirt obstructing the optical port causespoor transmission. The thin dimension results in a low weight for given length when comparedto electrical cables. However, being thin and somewhat brittle in nature, fiber tend to breakeasily if bent beyond a certain limit a direct viewing into the optical point can be harmful to theeyes.

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10. MAINTENANCE.

The subject of maintenance of Automatic Telephone Exchange can be broadly divided undertwo categories: -

1. Prevention of Service Failures.2. Location of Faults and their removal.

Prevention of Service Failures can be done in following ways: -1. Suitable design and adoption of suitable adjustment standards of the equipment parts of theexchange can minimize failures in service.

2. Some preventive measures may also reduce service failures viz. keeping the rooms dust free,maintaining temperature and humidity under tolerable limits using air-conditioners etc...

3. Routine inspection, routine tests and routine adjustments also help in preventing servicefailures.When faults occur in some parts of the exchange, they should be detected and removed asquickly as possible.

Various tools are also used to check the faults in the telephone lines.For checking fault inside the exchange

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11. REFERENCE

A) www.bhelhwr.co.in

B) www.wekipedia.org/wiki/bharat_heavy_electricals

C) Telecommunication systems Engineering BY Willilam C. Lindsey

D) V.K Joshi (senior Technician in BHEL , Haridwar)

E) www.thehindubusinessline.com/companies/bhel-sets-rs-8379cr-target-for-201213/article3272758.ece

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