A

SUMMER TRAINING REPORT

SUBMITTED TO

ARYA COLLEGE OF ENGINEERING I.T.

TAKEN AT

INTRUMENTATION LTD. KOTA

(25 May 2009 to 24 June 2009)

Submitted to:                  Submitted By:

Miss SHUBA ARYA SUMNESH SAXENA

7th Sem, E.C.E. ( Roll No. 74)

Arya College Of Engineering & I.T.

ACKNOWLEDGEMENT

First of all I wish to express my sincere thanks to the Rajasthan Technical

University, which introduce the scheme of providing practical training for

technical student during the 4-year course of B.TECH.

With the drastic development of technology & speedy

industrializations of the country I consider my self to fortunate to have

undergone practical training in “INSTRUMENTATION LTD.”

I am very thankful to Mr. S. KHATRI (Head of Training Department, I.L) &

other concerned person of IL, Kota for their guidance, constant encouragement,

strong support & kind help of understand many technical aspects in my training

period.

.

SUMNESH SAXENAB.TECH. 4th year.Branch – ECECollege – Arya College Of Engineering & I.T.

PREFACE

I took my practical training of 30 days from 25-05-2009 to 24-06-2009 at

“INSTRUMENTATION LIMITED “ which is a govt. of India enterprises. According to

the rule of Rajasthan Technical University towards the fulfillment of 4 years degree

course of B.TECH. We are supposed to go training of 30 days after 3rd year.

The object of practical training in engineering filed is to co-relate the theory

with practical knowledge & to make student familiar with industrial environment.

I have been fortunate to get practical training in such a industry which has

been continuous by climbing the ladder of development utilizing the latest technology,

here I could gain knowledge of various equipment which are tested & calibrated in the

enterprise.

My report that follow is the summary of all the knowledge that I gained

additional.

SUMNESH SAXENA

CONTENTS

S .No . PARTICULARS PAGE No.

1. INTRODUCTION 04

2. CARD ASSEMBLY 06

3. RAILWAY SIGNALING 19

RELAYS

4. GAS ANALYZERS 29

5. U.P.S. 31

6. QUALITY ASSUARANCE 36

7. TELECOM CENTRE 38

8. CONCLUSION 45

9. BIBLIOGRAPHY 46

INTRODUCTION

“INSTRUMENTATION LTD, KOTA” is a govt. of India enterprises established in Kota

(Raj.) in 1966-67 with the prime objective of attaining self-reliance in the field of

contract & automation for the process industry.

The major products that IL presently manufacturing are: -

1) Process control Instruments

2) Control Valves

3) Railway Signaling System

4) Sets of Telecommunication

5) Microprocessor Based Recorders

6) Digital switching system

7) Rural Automatic Exchange

8) Main Automatic Exchange

9) Panels

10)Defense Products

Today, IL is supplying these control Equipments to various sectors of the industries viz.

power, steel fertilizer, chemical, petrochemical, refineries, cement, paper textiles,

space, oil, gas, the turn over target is more than 150 cores.

It has its plant at Kota, Palakkad with over 25 years of experience and a dedicated

work force. IL has measured all complicities of control system requirements can lead

you right through your project from system design detailed engineering, manufacturing,

installation final commissioning to after sales services & customer training.

IL after establishing itself as an undisputed leader has crossed the Indian border to

supply equipment on turnkey basis in International market. It has supplied

instrumentation on turn key basis for 2 thermal power stations in Malaysia &

established a service center at kufa complex in Iraq, supplied instrumentation for

Ethiopian Petrol company of Ethiopia, supplied instrumentation for Esphahan steel

plant Iran & also a major break through has been made in capturing the market for Hi-

tech digital control system for refineries in the USSR.

All work-center of IL, are well equipped & appropriately upgraded with manufacturing

capability & capacity. The men power are well experienced & also given exposure to

various new technologies. To meet the equipment in working environment, all work

places are adequately dust controlling.

For assembly &testing of hi-tech electronic instrument, totally dust free air conditional

hall are used with static protection.

With the development of technology & speedy industrialization of the country,

I consider myself fortunate one to have undergone practical training in

“INSTRUMENTATION LTD, KOTA”

There are 9 departments or sections in Kota unit:-

(1) Assembly Shop

(2) Telecom Division

(3) Digital Electronics Unit

(4) Maintenance Shop (Electrical)

(5) Railway Relay

(6) Gas Analyzer (Production)

(7) Defense Project Department

(8) PCB Centre

(9) UPS centre

I have visited following sections during my training period that are:-

(1) Card Assembly (PCB centre)

(2) Railways Signaling Relay

(3) Gas Analyzer

(4) UPS (Engineering, Production, Servicing)

(5) Telecom Division

Card Assembly (PCB Centre)

Types of card assembly

1. Through-hole (TH)

2. Surface Mount Technology (SMT)

Surface mount technology (SMT) IS AN ELECTRONICS ASSEMBLYTECHNIQUE

where electronic components are mounted to the surface of printed circuit board

without holes drilled through the board for insertion of component leads. The SMT

devices must be precisely placed on the circuit board and held in the position by solder

paste or glue until the soldering process, which is usually automated, can make

connection.

BENEFITS OF SMT

Reduction in package size results in greater functionality in the same board

area.

Reduction in weight, mobile and handhold electronic items such as video

cameras and cellophanes are example, which have low weight and high

performance.

Reduction in noise. This is primarily due to small electrical paths compared to

leaded components.

Higher operating speeds due to shorter interconnects.

Types of assembling

1. Full SMT board with parts on one or both sides of the board.

2. A combination of through-hole and SMT components.

3. Only through-hole components.

Assembly Procedure for SMT

Surface mount assembly is basically a four-step process:-

1. Print the solder paste/ glue.

2. Place the components.

3. Reflow the paste to form the solder interconnection between the component and

the land area of the board.

4. Clean up.

Equipments used

1. Screen Printer- To print the solder paste / glue on the board.

2. Pick & Place Machine – To place the component on the printed board.

3. Re-Flow Oven – To place the component on the printed board.

4. Wave-Soldering Machine – For soldering of Through – Hole components.

From equipment standpoint, the pick & place machine is the most complicated. It alone

performs functions handled by three to four machines in standard through – Hole

assemblies. The manufacturing line is much simpler, uses less space, requires few

manpower, have a shorter cycle time.

Advantage of SMT

SMT allows production of more reliable assemblies, increased board density, and

reduced weight, volume and cost. Considerable cost saving can also be realized

through a reduction in material as well as the labor costs associated with automated

assembly.

Pick and mount machine:-

This machine is very important it is only one machine at IL , Kota in Rajasthan. This

machine is very costly (6 crores Rs. /-) It picks up small component. With the help of

programming we put in the computer and mount on the PCB. This machine mount

small Component on the PCB at first after this we solder the PCB. After this we solder

the PCB component after this we take out card and test it. When any component short

then we check it manually and remove difficulties and after we give to testing after

testing we clean the card and lequer.

Soldering machine: - It is a big machining in which we insert the card and there is

a sensor. We pass the card on the heating plate. This plate is divided in to three parts

first part is low heated, second one is higher heated and third one is very higher

heated. After this card and heating plat distance is large due to the pullges after this we

pass the card on the melt liquid of Ag+Sn+Pb. Then card is solder by the liquid. Temp.

2400c and we soldered 10 cards at a time and card soldering time is one second.

Activity Flow Chart

COMPONENT FORMING

c

ASSEMBLY OF PCB’S

RECTIFICATION

PRE-SOLDER INSPECTION

KITS FROM STORE

SOLDERING OF PCB’S

CLEANING

REWORK

POST SOLDER INSPECTION

TO TESTING & REPAIR CENTER

Various assembly Processes:-

1. Issue of Kits (Kit Marshalling & Receipt of kit)

2. Numbering

3. Baking

4. Mechanical Assembling

5. Mounting

6. Pre-Solder Inspection

7. Soldering

8. Rework and Touch Up

9. Post-Solder Inspection

10.Final Dispatch

1 .Issue of Kits:

During the assembly of PCB’s several operations are required initially various

components which are required for the purpose of assembly are received from the

store, in the form of kit then following process are made on the PCB’s before final

clearance and dispatch to the testing and repairing center.

2 . Numbering:-

The purpose of numbering the PCB’s is to lay down the procedure for identification &

traceability of the products. The PCB’s are identified at the initial stages and higher

stages by providing the serial no. on them which is of 10 digit code.

3. Baking: -

Before proceeding to the various operations, the baking operation is done due to

following : -

During soldering the card passes through temperature range in

pre-heating and soldering chamber. If baking is not done prior to soldering the card

may be distorted at high temperature. During baking the card becomes dry & it can

bear thermal shocks during soldering.

The baking is done in a furnace at 1200c. The baking erent cards.

It is 1 hour in use of simple layer.

4 Hour in case of 2-4 layers.

8 Hour for above 4 layers.

4 .Mechanical Assembly:-

Although we are using the electronic components in assembly. But some

components are assembled fastened by mechanical tools fasters. Components which

are mechanically assembled are connectors, injectors, switches etc. components,

which are assembled on later stages are:-

1. Those components, which may be spoiled during soldering.

2. Those components that may be provide obstacle during soldering.

5.Mounting:-

After exception of kits mounting is done with the help of following

steps:-

A. Forming: -

After receipt of kit of required PCB, which is to be assembled, the Forming

operation is done with the help of component list (C.L.) in the Following steps: -

Cutting: -

Several components bear long leads & these leads may create problem in

soldering. Hence leads of such components cut in the required length with the

help of required tool.

Bending: -

These are some components, which can’t be used directly in their original

shape. A particular pitch (specified length) is there the leads of their length

components are given the required shape with the help of required tool. The

pitch distance is also maintain during the pending now it become the easiest &

perfect to maintain the pitch distance through tools.

B. Binning: -

With the help of component list, all the components are kept in different boxes

called BINS. It makes simple & easier to mounting of components on the card.

It is done in order

Save product cost

Saving labor cost

C. Mounting: -

During forming operation, the components are kept in different bins (boxes). The

cutting and bending operation is performed. For the required components, now

the components are ready for mounting purpose. The assembler purpose. The

assembler start mounting of there formed components. These are mounted on

PCB’s with the help of proper tools does the mounting properly (manually)

6.Pre-solder inspection: -

As soon as the mounting is over these assembled cards are offered for inspection,

which are known as Pre solder inspection. If any mistake is there in mounting it is

reworked by the assembler and if mounting is ok then these are send for soldering.

7. Soldering: -

These two types of technique are used for the soldering of PCB’s.

A. Through Hole Technology

B. Surface Mount Technology [SMT]

A.Through Hole Technology : -

In this wave-soldering machine are used for soldering through hole components

of the printed circuits.

Wave soldering: - It is done by using the wave-soldering m/c. The wave

soldering is the process consisting of 5 sub process:-

1. Fluxing

2. Pre heating

3. Wave soldering

4. Cleaning

1. Fluxing: -

Fluxing is done to remove the oxidation and other containments; no clean

flux is used as solvents. Fluxer is of form Fluxer type. Excess flux is removed

by using the air knife arrangement.

2. Pre-heating: -

After fluxing & removal of excess flux, the PCB moves to the pre heating

section, where the solder side of the PCB receives hot radiations from

heaters & this the oxidation & other continuation. The PCB is completely dry

& it can bear thermal shocks. Here 6 heaters are there. Their temp, Rises

gradually giving rises of 20 to 250C by each. Heater temperature rises from

220 to 3600c.

3. Wave soldering: -

After pre-heating. We move to wave soldering. Different cards on which the

components like transformer, high power resistance, capacitance to be

mounted are placed on system and soldered by wave soldering.

In WAVE SOLDERING MACHINE ……

a) The card is placed on the card carrier having an arrangement of motion

through bearings and magnets are mounted on it.

b) Now the PCB is placed over foam flux. The flux is isopropyl alcohol which

removes the metal oxide layers on the pins of the component. Here ,

compressed air is mixed with flux to produce foam flux.

c) The PCB is then passed through heater which pre-heat the PCB from

240*C to 340*C temp. The heating is provided in six stages of

temperature range from 240-260-280-300-320-340*C. This is done

because :-

1) To avoid explosion when the cold flux directly comes in contact to hot

solder at 240*C

2) The flux reacts readily with metal oxide layers.

3) The bakelite melts on sudden increase in temperature so to avoid this,

slow heating is done on sudden cooling also, bending in PCB occurs

which destroys the internal connection, so it is also gradually cooled.

4. Cleaning: -

After soldering PCB’s are cleaning by isopropyl alcohol.

B. Surface Mount Technology (SMT): -

In this, flow-soldering method is used for soldering the surface components of

printed circuits. This method is a very efficient and fast technology. It saves the

cost of placing the component &time about 30% more faster than the work

power.

A machine known as PICK AND PLACE machine carries out this

method. It is a semi-automated machine, which works in two planes X & Y

plane. The capacity of this machine is 20,000 components per hour. Pick and

Place machine can be divided into two parts: -

a) PICK AND PLACE machine

b) REFLOW OVEN

a) PICK AND PLACE machine: -

There is fully automated programmable pick & place machine model vitesse of

M/S EUROPLACER.The machine is most versatile. It can place not only chip

components but also components in trays,tubes & tapes.

(close view of pic and place machine)

Important Features of an Automatic SMD Pick & Place System

Component Size: 0402

Component Placement Speed: 20,000Component/hour

Feeder Capacity: 198 feeders.

Ability to handle all type of components, in tape, sticks and trays . Quick

Changeover.

Vision correction to align leaded components.

Head: Two head with 8 nozzles.

Software: The software is window NT based operating program can be

used ON-Line as well as OFF-Line. System.

b) REFLOW OVEN: -

After placing the SMT component on PCB, the PCB is checked

manually and then sent to reflow oven. In this, six stage of heating is

provided from 240*C – 340*C. This temperature range is changed with

the help of a programmed panel.

8. Rework & Touch-up: -

After soldering & cleaning, rework is done. Its advantages are: -

a). Solder defects are rectified

b). Proper touch up is given

9. Post-Solder Inspection: -

It is also called final Inspection. When PCB’s are complete in all aspects, final

inspection is done. After inspection, these are ready for dispatch.

10. Final Dispatch: -

After final Inspection, ejectors are mounted and components, which are assembled

after soldering, are fastened. Then these cards are sent to testing and repair center .

Instrumentation Limited state-of- art Electronic assembly’s plant at Kota is equipped to

assemble & test the PCB’s for through – hole, SMT & combination of both. The unit set

up is clean, Dust free & AC environment, ESD protected. The centrally air condition

PCB assembly & testing area is spread over 20,000 square feet.

Process Capabilities

Fully automatic SMD Double sided SMD & PTH

Fine pitch placement 12 mil BGA Placement 0.04 mm.

Passive Placement 0204 BGA & fine pitch rework

No clean / water soluble solder

Paste & flux conformal coating

Electro-mechanical system assembly

Complete turnkey final assembly

Of your product Functional card / system testing

Inward Good inspection

RAILWAY SIGNALING RELAYS (RSR)

REPORT

1. Introduction

2. What is a relay and where it is used

3. Related terms and their meanings

4. Components

5. Working

6. Calibration

7. Specification of various relays manufactured at instrumentation Ltd. Kota

1. Introduction

Railway Signaling Systems are basically intended for dispatch and control of

trains in the fail-safe manner. These are most vital systems involving human

safety

I.L has executed large turnkey Railway signaling jobs for Western Railway,

Southern-Central Railway, RITES, IRCON, and NTPC etc.

2. What is a relay ?

A relay is a multi switch device with multiple mating contact pairs. The contact

configuration consists of two types of contact pairs-font and back. The back

contact pairs are normally closed and the front contact pairs are normally open.

When a relay is energized the status of front and back contact pairs reverses.

Relay manufactured at instrumentation limited (Kota) are electromechanical type

neutral line and track relays.

They works on the following two main operating principles:-

a. ELECTROMAGNETIC ATTARACTION

b. ELECTROMAGNETIC INDUCTION

The load current flowing through the magnetic coil generates magnetic flux in

the core and this flux is responsible for functioning of relays.

TYPES OF RELAYS:-

I.L manufactures three types of signaling relays. They are: -

a. LINE RELAY

b. TRACK RELAY

c. KEYLOCK RELAY

a) LINE RELAY: -

This type of relay is used for classification of line. It gives signal to lines for up and

down. There are two signals Red and Green. Here, red signal indicates that the line

is busy whereas the green signal indicates that line is clear.

b) TRACK RELAY: -

This type of relay is used for changing track at railway station. As we know only

two lines up and down are present & number of lines are present at railway station.

c) KEYLOCK RELAY: -

These are automatic relay & are used for the protection of accidents when train

arrives &gate is automatically closed. These all types of relays are controlled at

control room

3. Related terms and their meanings:-

Pick up voltage/current:

Minimum voltage/current at which relay operates i.e. normally closed

contact pairs change to normally open.

Drop away volt /current:

Maximum voltage/current at which relay releases fully. i.e. The contacts

acquire their normal positions.

Contact gap:

The voltage/current variation between the first back break and the last

front make, when the voltage/current applied gradually increasing step by step.

Ultimate pick up: -

Minimum voltage/current at which the armature touches the core of the

coil. Ultimate pick up is achieved after all the front contact achieves ‘close’

status.

Operating time: -

The time that is taken by the relay from application of voltage to change

of state of contacts. This is taken on each contact.

Release time:-

The time taken by the relay from removal of rated voltage to change of

state of contacts.

4. COMPONENTS:-

Relay broadly consists of:

a. Contact block assembly

b. Magnetic assembly

c. Armature assembly

d. Relay base

Contact block assembly:

Contact block assembly mounted on the relay base consists of ten

contact blocks. The first two from the coil end are for coil termination and the

rest are used in pairs as mating contacts. The two contacts in each pair

consist of one silver and one sig (silver impregnated graphite) contact. Each

contact block consists of maximum four contacts that can be either silver or

sig contact depending on the configuration. Each contact has a

corresponding mating contact of other type in the adjacent contact block

hence the two forming a switch. The operating card supported by adjust

spring at one and inserted in the slots provided in the operating arm at the

other, is interwoven in slots provided in the contact springs so as to move

only the silver contacts. The sig contacts are kept in position by the slots

provided in adjustment card, which in turn are supported at one end by

suppurated at one end by support spring and by adjustment card bracket at

the other.

Magnetic assembly:

Also mounted on relay base, the magnetic assembly consists of coil,

yoke, pivot plate; adjustment card bracket and armature return spring.

Armature assembly:

The armature riveted with the operating arm is pivoted on the pivot

plate such that it can rotate a small angle in the plane perpendicular to the

line of the armature and the pivot plate.

WORKING:-

As the relay is plugged in the plug board it becomes operational. The contact

pairs are connected with the circuit receiving 3v.. The coil on the other hand receives

supply in two modes-no supply (off) and full supply (on). Full supply given to the relay

is enough for the relay to pick up (energize) and their values (either in current or in

voltage as in case of track relay and line relay respectively) depend on the specification

of the relay. When the coil supply is in ‘off’ condition the back contact – pairs are in

‘open’ status.

As the supply is given to the coil, it develops a magnetic field that attracts the armature

towards itself, since the armature is a magnetic material. The magnetic field provides

the torque for the armature to rotate about the pivot. The magnetic field developed by

the coil depends on the current within. This current will however increase to its peak

value from zero (initially) following exponential curve because of the reverse magnetic

field developed due to induction effect. When the torque on the armature due to

magnetic field increase enough to overcome the opposing the torque of armature

return spring and operating cards, the relay energize and the armature rotates about

the pivot. The operating arm rotates with it. However the rotation if operating arm can

be visualized as linear movement in the direction parallel to the relay since the angle of

rotation is small. This linear movement is transferred to operating card and in turn to

the silver.

CALIBRATION:

Calibration involves adjustment of various electrical and mechanical parameters

for proper functioning of Relay. Calibration is done on a special stand and with tools

made for this purpose. The parameters that are adjusted are:

Pickup / Drop away voltage:

The relay should energize and energize at specific voltage / current. These

parameters are function of various torque acting on armature assembly viz. magnetic

force, armature return spring force and the operating card force. For adjustment the

last two forces are varied to obtain the desired effects.

Contact Pressure:

The SIG contact springs should press against the adjustment card slots with a

pressure not less that 40 grams, this pressure is introduced in the springs by bending

machines at the manufacturing stage. However little adjustment if required, is done at

calibration stage. Tension gauges of suitable range measure the pressure. The

pressure is required to ensure proper contact between silver and SIG contacts.

Contact gap:

Ideally all back contacts should break simultaneously and all the front contacts

should make simultaneously as the relay energizes. But this is not achieved in practice.

So, out of all the back contacts, usually there is one contact to break first and one to

break last Likewise there is one front contact to make first and one to make last. The

voltage / current variation between first back break and last front make should be less

than 0.6V.

None overlapping:

The distance traversed by the contact assembly between the last back contact

break and the front contact make should be not less than 0.3 mm. This is ensuring that

any font and back contacts do not achieve ‘close’ status simultaneously. Test

conducted to achieve this at inspection stage is non-bridging test.

Thrust:

Whenever the silver and SIG contacts mate, the silver contact pushes the SIG

contacts to ensure firm contact. The SIG contacts that are supported by the edge of

adjustment card at its free end moves away from the edge by a distance that should be

not less than 0.4mm. The calibrator with the help of feeler gauge ensures this distance.

Specification of relays manufactured at Instrumentation Ltd. Kota

Type of Relay Rated Pick Up (PU) Drop Off Contact from Contact

Resis

Coil

Resis at

20 C

Relevant

Standards

Q Series neutral line

Q Series neutral line

Q Series neutral line

Q Series neutral line

Track plug in type

Track plug in type

Volt Curr (mA) Volt Curr(mA) Volt Curr(mA

)

Front Back Mohm Ohm

BRS 930 A/

IRS 23 , 34

-Do-

-Do-

BRS

939A/IRS 23,

34

BRS

939A/IRS 23,

34

24

24

24

24

1.4

1.4

80

80

109

109

156

156

< 19.6

< 19.6

< 19.6

< 19.6

-

-

-

-

-

-

120-140

103-117

>3.6

>3.6

>3.6

>3.6

-

-

-

-

-

-

>68%PU

>68%PU

12

8

12

8

2

2

4

8

4

8

1

2

<200

<200

<200

<200

<200

<200

300

300

220

220

9

9

CAULKING OF AG CONTACT

OPERATION MACHINE IN USE

1. Ultrasonic Cleaning of Contact Block 1. Set of Vibronics ultra Sonic Cleaner

500W

2. Caulking 2. Hydrauallic press 2.5T [Hydrauallic

Press

Machine]

3. Checking of contacts by S. blade OK

NOT OK

4. Spot Welding 4.Spot Welder 120 Watt

5. Soldering 5.Soldering Machine

6. Ultra sonic Cleaning of fixed 6.Set of Vibronics Ultra Sonic cleaner

500W

Contact Assembly (SIG)

7. Polishing

8. Bending

9. Vapour Degreasing 9.Vapour Degreasing Plant

10.Baking of fixed contact assembly 10.Furnance

OA ASSEMBLY:

For the production of railway signaling Relay. We required following test stand.

1. IR / IS TEST

IR Test at 500v.dc

IS Test at 1 kV, AC (1 to 2 sees)

Both the test conducted in b / w

(a) Body to terminal (BT)

(b) Terminal to Terminal (TT)

2. NON – BRIDGING TEST

1. Test of physical gap b/w Back and Front Contact at 500v DC

3.ACIMMUNITY TESTING

(1) 300 V, ac (Gradually) Back contact should not break.

(2) 300V, ac (Abruptly) Back contact should not break.

(3) 1000V, ac (Abruptly) Front contact should not make.

GAS ANALYZERS

Gas Analyzers are the instruments used for continuous measurement of percentage of

a particular gas in a gas mixture. It plays an important role in process engineering

where it provides information on composition of a gas mixture in the process leading to

straight forward quality control and cost saving. On the basis of values obtained from

the gas Analysis, there is a possibility of correcting the process and altering it in such a

manner that it is optimized.

Based on the principle of measurement there are broadly following types of Gas

Analyzers that have been manufactured / supplied by IL Kota:-

S.NO. TYPE OF ANALYSER GAS MEASURED

1. Paramagnetic O2

2. Thermal Conductivity H2, SO2, CO2, Ar

3. Infrared CO, CO2, SO2, NH3

4. Zirconia’s Probe type Analyzer O2

All the above Analyzers are continuous measuring type Analyzers i.e. the gas available

in the process which is to be analyzed is continuously fed to the Analyzers, it gets

measured and then goes to exhaust. However the process gas is normally not suitable

for directly feeding to Analyzers. A gas sampling system is used to make the process

gas suitable for feeding to the Analyzer. The sampling system consists of following

accessories:-

1. Gas sampling probe

2. Heating device

3. Condensate removal and filtration device

4. Sample gas cooler

5. Diaphragm pump

6. Pressure Reducer

7. Flow meter

Working Principle:-

1. Paramagnetic Analyzer: - it works on the principle that out of all the gases

oxygen is a gas which is highly paramagnetic in nature i.e. the molecules of

oxygen gas have got the property to get attracted by magnetic field. Based on

this analyzer is used for measurement of oxygen.

2. Thermal Conductivity Analyzer: - this Analyzer works on the principal of

different thermal conductivities of different gases. Hydrogen is a gas, which has

very conductivity as compared to other gases like nitrogen, argon etc. this

analyzer is used in thermal power plants for monitoring of H2 in Turbo generator

cooling.

3. Infra Red Analyzer: -This analyzer works on the principle that all Polly atomic,

non-elemental gases absorb the infrared radiation selectively in a particular

bandwidth or frequency spectrum. Based on this specific absorpt ion of infrared

radiation, the IR analyzer is used for measurement of co, co2, ch4, nh3, and

hydrocarbon etc.

4. Zirconia’s Probe Oxygen Analyzer:-This analyzer work on the principle that a

disc of zirconium oxide material acts as a solid electrolyte, when it is subjected

to different partial pressure of oxygen on its two sides. The mV generated

across the 2 sides of the Zr O2 disc is governed by Nernst equation:-

Emf= KT log 10 (P1/P2)

P2= partial pr. Of O2 in measured gas on one side.

P1=partial pr. Of O2 in reference gas on other side.

T= Absolute temperature.

K= an arithmetic constant

C= cell constant

In the above equation since all other are constant, the Emf generated is a function

of P2 I e % of O2 in measured gas.

UPS (Uninterrupted Power Supply)

What is UPS: -

The basic UPS consist of rectifier/charger, inverter, external source of stored power

(usually a battery), associated circuitry, protective devices and accessories for proper

operation. The basic function of UPS is to continue power supply to critical load within

its specified tolerances during a failure or deterioration of the normal power supply.

Continuity of electric power to critical load shall be maintained for emergency period

with the UPS supplied externally stored power up to the specified time or until the

restoration of normal power source.

Necessity of UPS: -

Main AC is not clean power. It has inherent defects & poses to danger to

sophisticate & sensitive electronic instruments. The sensitive load is frequently

subjected to voltage variation, transients, interruption and frequency variation.

According to IBM the UPS Systems are capable to overcome 99.9% of power line

disturbances.

The most common kind of main disturbances are as follows: -

Disturbances Equipments used

Voltage Variation Voltage Stabilizers

Electrical Noise Insulated Transformer

Frequency Variation UPS

Large Harmonics UPS

Power Failure UPS

The disastrous consequences of such disturbances are now well known to users of

computers. They cause:

Lost data

Scrambled data

Component failures

Down time of complete equipment

Basic Types of UPS: -

OFF LINE UPS

ON LINE UPS

OFF LINE UPS: -

BATTERY

BATTERY

CHARGER

INVERTER

INPUT

In OFF LINE UPS input is directly connected to output.

Inverter is not used in this type of UPS.

Output will be in square form.

Because input is directly connect to output so to reduced disturbances a Buck-

Boost converter is use.

Frequency may vary according to input applied.

ON LINE UPS: -

BY PASS

Static Switch

BATTERY

In ON LINE UPS Input is connected to load through inverter.

Output is in sine form.

Frequency of output is constant.

BATTERY

CHARGER

INVERTER

INPUT

In case of inverter failure there is an emergency system called BY PASS to

directly connect input to output load.

WORKING of UPS: -

The UPS System basically consists of Rectifier, Inverter, Transfer Switch and

Battery.

Under normal condition, the battery charger supplies the entire power necessary

to the inverter for supplying the load, and simultaneously charges the battery in float

charging condition. The battery charger affects charging the battery automatically.

If power failure occurs, the inverter is supplied the DC power from battery and

supplies continuously the stable AC power to the load. After restoration of power the

UPS come back to normal operation.

The transfer switch or static switch is used to transfer load from inverter mode to

bypass mode. In case inverter becomes faulty the load is transferred from inverter to

Bypass automatically.

The battery used in home segment is generally Lb-Acid tubular (wet type)

batteries and require maintenance periodically. The most critical part of maintenance of

battery is to keep level of acid to required level by adding distilled water. Also the life of

battery is of 2-3 years.

In UPS it is general to use Scaled Maintenance FREE Batteries that do not

require any topping of distilled water. These batteries also have limited life of 2-3 years.

However SMF batteries are very sensitive to temperature and their life reduces

drastically if temperature goes above 25 deg C. So it is batter to keep UPS in cooler

places.

Parallel Configuration of UPS: -

To increase the reliability, UPS should be used in parallel redundant

configuration. In this load is equally shared by both UPS, in case of failure at any one,

full load is taken by other UPS . If both UPS fail, then the load is transferred to by pass.

Battery: -

Battery plays an important role in UPS. The higher the back up time, more

batteries are required . This adds cost to the battery and stronger chargers required to

charge the battery. Further batteries have definite 3 to 5 years of life. Also, the life of

batteries gets further detiorated due to high environmental temperature. Therefore,

batteries suitable only for optimum battery back up time must be taken and UPS must

be backed up with a generator to take care of large duration of power outage.

Application: -

In critical and higher end application such as power plants, refinery or industries

using computer-controlled equipments, all the instrumentation & critical loads are on

UPS supply. Failure of controls and tripping of plants causing tremendous loss. As

such reliability of UPS power supply are very important parameter. This is achieved by

using higher configuration of UPS. In one such configuration called parallel redundant

configuration, two UPS are used with their output paralleled. During normal operation

both the UPS supplies 50% load. In case of failure of one UPS or taken out for

maintenance, the other UPS automatically start supplying 100% load. In the worst case

when both UPS fail load is transferred to Automatic Voltage Stabilizer without break in

load through static transfer switch.

QUALITY ASSURANCE

The Eight Quality Management Principles

Each major clause of ISO 9001-2000 has been based upon the following eight Quality

Management principles:-

Customer Focus: Organizations depend on their customer and therefore should

understand current and future customer needs, should meet customer requirements

and strive to exceed customer expectations.

Leadership: Leaders establish unity of purpose, direction and the internal environment

of the organization. They create the environment in which people can become fully

involved in achieving the organizations objectives.

Involvement of people: People at all levels are the essence of an organization and

their full involvement enables their abilities to be used for the organizations benefits.

Process Approach: A desired result is achieved more efficiently when related

resources and activities are managed as a process.

System approach to management: Identifying, understanding and managing a

system of inter related processes for a given objectives contributes to the effectiveness

and efficiency of the organizations.

Continual improvement: A permanent objective of the organization is continual

improvement.

Factual approach to decision making: Effective decisions are based on the logical or

intuitive analysis of data and information.

Mutually beneficial supplier relationships: the ability of the organization and its

suppliers to create value enhanced by mutually beneficial relationships.

QA-UPS

For the purpose of quality of UPS following test are taken:-

1. Temperature testing (At 19deg C and at 40 deg C).

2. After exhausting the battery of UPS again temperature testing.

3. Output should be fixed given by manufacturer.

4. Testing of rectifier output, inverter output and battery output.

5. Ripple testing between battery and rectifier.

QA-PCB

Two types of inspection are there for the purpose of quality assurance

1. Pre solder inspection

2. Post solder inspection

1. Pre solder inspection: -Following inspection are there in pre solder

inspection: -

Card should not have any component having wrong value at any

particular position.

Card should not have defective component.

Card should not have any missing component.

Card should not have any lifted component.

2. Post solder inspection: - Following inspection are there in pre solder

inspection: -

Card should not have any component having wrong value at any

particular position.

Card should not have defective component.

Card should not have any missing component.

Card should not have any lifted component.

Card should not have any solder defects.

Card should not have any unsoldered component.

No shorting should be there.

No disconnection should be there.

TELECOM TECHNOLOGY

This field of telecommunication has evolved from a stage when signs, drum beats and

semaphores were used for long distance communication to a stage when electrical;

radio & electro-optical signals are used. Telecommunication networks carry information

signals among entities, which are geographically apart. Long distance voice

communication is “Telephony”. Early switching systems were manual and operator

oriented. Limitations of operator switching systems were quickly recognized and

automatic exchanges came into existence. Automatic switching can be classified as

electromechanical and electronic. Electromechanical switching systems and are batter

known as strowger switching systems.

With the introduction of automatic switching system various disadvantages of

the manual exchanges were overcome; some of them are:

In a manual exchange the subscriber needs to communicate with the operator

and a common language becomes an important factor. In multilingual areas

this aspect may pose problem. On the other hand, the operation of an

automatic exchange is language independent.

A greater degree of privacy is obtained in automatic exchanges, as no

operator is normally involved in setting up and monitoring a call.

Establishment and release of calls are faster in automatic exchanges. It is not

unusual in manual exchange, for an operator to take quite a few minutes to

notice the end of a conversation and release the circuits. This could be very

annoying particularly to the business subscribers who may like to make a

number of calls in quick succession.

In an automatic exchange, the time required to establish and release a call

remains more or less of the same order irrespective of the load on the system

or the time of the day. In a manual switching system, this may not be true.

However the major disadvantages of this stronger system is its dependence as

moving parts and contacts that are subjected to wear and tear. Also the control

functions in the stronger systems are performed by circuits associated with the

switching element in the system. However in the cross bar system the call

switching equipment and the call control equipment are separate. So these

stronger systems were replaced by the Cross Bar Switching Systems, which

were designed using the common control concept.

INTRODUCTION TO TELECOM DIVISION: -

Telecom division comprises of: -

a) Manufacturing / production

b) Quality Control

c) Production Planning & System

d) Evaluation & Revalidation

e) PCB Assembly Shop

I.L has been pioneer in manufacturing, supplying & servicing of Electronic

Telephones Exchanges based on C-DOT (Centre for Development of Telematics). C-

DOT provides economical means for serving metropolitan, web on & rural environment.

C-DOT has high traffic / load handling capacity up to 8,000,000 BHCA with termination

capacity of 40,000 lines as local exchanges. Thus C-DOT is easy to maintain & highly

reliable.

C-DOT DSS BUILDING MODULES

C-DOT DSS consists of following basic modules: -

a) BASE MODULE

b) CENTRAL MODULE

c) ADMINISTRATIVE MODULE

d) INPUT OUTPUT MODULE

A) BASE MODULE (BM): -

BASE MODULE (BM) is the basic growth unit of the system. It interfaces the

external world to the switch. The interface may be subscriber lines, analog & digital

trunks. Each base module has Interface up to 2024 (2K) terminals. The number of

base modules directly corresponds to exchange size. It carries out majority of calls

processing functions & operation maintenance function with the help of Input Output

Module

FUNCTIONS: -

a) Analog to Digital conversion of all signals on analog lines & trunks.

b) Interface to digital trunks & digital subscriber.

c) Switching the calls between terminal connected to same base module

d) Communication with the administrative module via the control module for

administrative functions

BASE MODULE hardware is spread over four units: -

a) Analog Terminal Unit (ATU): -

For interfacing analog lines & trunks & provides special circuits.

b) Digital Terminal Unit (DTU): -

For interfacing trunks i.e.; MBPS PCM lines.Each digital trunk

synchronization (DTS) card along with the digital trunk channel associated signaling

(DTC) card interfacing 30 digital trunks.

c) Time Switching Unit (TSU): -

It has a time switch for time switching with in the BM, a control switch for

control message communication within the BM & between BM and a service unit for

providing call processing support services

B) CENTRAL MODULE (CM): -

CENTRAL MODULE (CM) is responsible for inter base module calls,

communication between BM & AM and providing local clock and network

synchronization. For this function, CM has a space switch controller and a control

message switch.

CM provides connectivity up to 16 BM. Each BM interfaces with CM via two

512 channel parallel buses each operating at 4 Mbps. These buses are called bus 0 &

bus 1 and each bus carries information of 512 subscribers transmitted by the BM in the

reverse direction after space switch controller (SSC) two parallel buses carry the

switched voice information of 512 subscribers each at 4 Mbps towards the BM.

C) ADMINISTRATIVE MODULE (AM): -

ADMINISTRATIVE MODULE (AM) performs system level resource allocation

& processing on a centralized basis. It performs all the memory and the time

processing support functions and also administrative functions.

D) INPUT OUTPUT MODULE (I/O M): -

INPUT OUTPUT MODULE (I/O M) is a duplex computer that interfaces

various secondary devices like disk drives and up to 8 serial ports for video display

units, which are used for man-machine interface communication

ELECTRONIC EXCHANGES

C-DOT was established with a view to develop a telephone switch to be the

standard equipment in the telephone exchange in the country. The telephone switch is

the heart of the telephone exchange & performs all operation required to connect

subscribers as and when they are desire.

The purpose of telephone exchange as switch is to connect any subscriber to

the other. The two subscribers may be connected to the same exchange or they may

be in the entirely different parts of world.

REMOTE SWITCH UNIT (RSU)

RSU is an integral part of C-DOT architecture. In order to realize a RSU, the

normal BM can be modified for remoting with host exchange via 2Mbps digital links.

The number of 2 Mbps links between the main exchange & RSU is primarily

determined by the traffic. A maximum 16 PCM links can be provided between RSU

main exchanges. Analog & digital trunk interfaces are also implemented in RSU to

support direct parenting of small exchanges from RSU into itself instead of parenting it

to main exchange, which will ultimately save the media required from main exchange.

As far as call processing is concerned, RSU is an autonomus exchange capable of

local call completion operation & maintenance function is handled by the host

exchange. In case of failure of PCM links, RSU goes into stand-alone mode of

operation. In this case, it is not possible to process a call request due to unavailability

of links to the heart & the subscriber is connected to the appropriate tone or

announcement.

During stand-alone mode of operation, the local and incoming termination

calls in RSU are switched and the metering information of the entire RSU subscriber is

stored in the RSU. From there, it is sent to the host whenever the PCM links are

available again.

RURAL AUTOMATIC EXCHANGE (RAX)

C-DOT 128 RAX is a stored program controlled switching system with a

capacity of 128 termination. These termination includes subscriber lines, trunk to other

exchanges, tones etc.

128 RAX has been designed to work as a terminal exchange to the

requirements of rural areas. It can be interfaced with all type of switching equipment

working at present in Indian Telecom Network.

FEATURES: -

a) Non blocking transmission & switching networks

b) Real Time Clock.

c) On Line maintenance.

d) Redundancy

e) Field programming.

f) Automatic System Alarm.

g) Automatic and Manual diagnostics

MAIN AUTOMATIC EXCHANGE (MAX)

The manufacturing of MAX has been stored from early 1991. MAX is

mainly used for local, tandem & transit application for rural, urban & metropolitan

areas. MAX is expandable, large capacity of the order of 2,000 lines or beyond.

The C-DOT DSS of different capacities can be put to use at various

switching modes in the telecommunication network.

FEATURES: -

a) Architecture is flexible to work as a remote module

b) 512 ports RAX is completely non-blocking.

c) It supplies concentration of up to 1:4 on lines.

INTERACTIVE VOICE RESPONSE SYSTEM (IVRS)

C-DOT IVRS is a computer telephony application where in subscriber calls are

answered automatically and the required information is conveyed to subscriber

depending upon service chosen and subscriber input in the form of announcements.

The C-DOT IVRS can also dial subscribers and convey suitable messages depending

on service chosen.

FEATURES: -

a) Low cost hardware and software.

b) Support global dyadic pulse and DTMF detection.

c) Implemented using DSP technology.

d) Multiple applications supported in single system.

e) Supports software packages used in Indian Telecom Network.

f) Applications are configurable.

CONCLUSION

Hence, in last I can say that taking training in such an organization provided to

very beneficial for me. I learn write a lot about UPS unit, PCB unit etc. I also got first

hand knowledge of how an industry practically works.

These all are necessary to know for an Engineering Graduate. Now we can

think a better in the field of an engineering industry by learning such things in the

systematic way.

At the end I would like to thank my co- workers and teachers who helped me in

preparing this meaningful report. I hope this report will be successful to make others

understand about the various technology and process used to prepare various

equipments.

BIBLIOGRAPHY

1) MANUAL PROVIDED BY I.L.

2) I.L website www.ilkota.in