dlw report

7/27/2019 Dlw Report

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ABOUT DLW

(DIESEL LOCOMOTIVE WORKS)

ORGANISATION

A flagship production unit of Indian Railways offering complete range of products in itsarea of operation with annual turnover of over 2124 Corer.

State of the art Design and Manufacturing facility to manufacture 290 locomotives perannum with wide range of related products viz. DG Sets, Loco components and sub-assemblies.

Supply of spares required to maintain Diesel Locomotives and DG sets. Unbeatable trail-blazing track record in providing cost-effective, eco-friendly and

reliable solutions to ever increasing transportation needs for over four decades.

Fully geared to meet specific transportation needs by putting Price - Value - Technologyequation perfectly right. A large base of delighted customers among many countries viz. Myanmar, Sri Lanka,

Malaysia, Vietnam, Bangladesh, Tanzania, Angola, to name a few, bearing testimony to

product leadership in its category.

Staff Status in DLW (As on 1st Oct'2009) Total Staff in DLW 5974,Production Staff2362

MILESTONES

Transfer of Technology Agreement

DLW entered in an agreement with General Motors of USA (now EMD) for technology oftransfer to manufacture high horse-power 4000HP AC-AC GT46MAC and GT46PAC

locomotives in India making India the only country outside North-America to have this leading

edge technology.

Returns from Transfer of Technology

First PKD WDG-4 locomotive turned out in August 1999. First DLW built 4000 HP *WDG-4 Freight loco turned out in March 2000. First DLW built 4000 HP WDP-4 loco turned out in April 2002.

Locomotive design projects

WDG4 locomotive with IGBT base TCC (Siemens & EMD) turned out. Indigenous AC-AC control for WDG4 (with distributed power controls). Indigenous AC-AC control for WDP4 (with hotel load capability) . WDP4 locomotive with IGBT base TCC & Hotel load capability.

*Note: Nomenclature (Naming) of DLW Locomotives:D Diesel Type

W Wide (width of gauge)


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G Goods P Passenger

M Multipurpose

x Any numbers in the name represent the horsepower (hp=x1000)A 100 hp

B 200 hp

C 300 hp ; and so on...Hence WDG-3A stands for Wide Diesel Goods- 3100 hp engine & WDP-4 represents WideDiesel Passenger- 4000hp 5

LOCOMOTIVES PRODUCED BY DLW

BROAD GAUGE MAIN LINE FREIGHT LOCOMOTIVE: WDG 3A

TECHNICAL INFORMATION

Diesel Electric main line, heavy duty goods service locomotive, with 16 cylinder ALCO engine

and AC/DC traction with micro processor controls.

Wheel Arrangement Co-Co

Track Gauge 1676 mmWeight 123 t

Length over Buffers 19132 mmWheel Diameter 1092 mm

Gear Ratio 18 : 74

Min radius ofCurvature

117 m

Maximum Speed 105 Kmph


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Diesel Engine Type : 251 B,16

Cycle.- V

HP 3100Brake IRAB-1

Loco Air, Dynamic

Train AirFuel Tank Capacity 6000 litres

BROAD GAUGE MAIN LINE MIXED SERVICE LOCOMOTIVE:

WDM3D

TECHNICAL INFORMATION

Diesel Electric Locomotive with micro processor control suitable for main line mixed Service

train operation.

Wheel Arrangement Co-Co

Track Gauge 1676 mm

Weight 117 t

Max. Axle Load 19.5 t

Length over Buffer 18650 mm

Wheel Diameter 1092 mm

Gear Ratio 18 : 65


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Maximum Speed 120 Kmph

Diesel Engine Type : 251 B-16 Cyl.

V type (uprated)

HP 3300 HP (standardUIC condition)

Transmission Electric AC / DC

Brake IRAB-1 system

Loco Air, Dynamic, Hand

Train Air

Fuel Tank Capacity 5000 litres

WDG4 - 4000 HP GOODS LOCOMOTIVE

Broad Gauge freight traffic Co-Co diesel electric locomotive with 16 Cylinder 4000 HP engine,

AC-AC transmission, microprocessor controlled propulsion and braking with high traction high

speed cast steel trucks.

Diesel Engine

16 Cylinder 710 G3B, 2 stroke, turbochargedafter cooled Fuel Efficient Engine


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Injection SystemDirect Unit Injector GovernorWoodward Compression Ratio- 16:1 Lube Oil Sump Capacity950 Lts

Transmission

Electrical AC-AC 6 Traction motor ( 3 in parallel per bogie). SuspensionAxle hung / taper roller bearing Gear Ratio90:17

WDP44000 HP PASSENGER LOCOMOTIVE

State-of-Art, Microprocessor controlled AC-AC, Passenger Locomotive Powered with 16-

710G3B 4000HP Turbo charged Two stroke Engine. Fabricated rigid design Under frame, twostage suspension, High Traction High Speed 3 axle (HTSC) light weight cast truck frameattribute to high adhesion performance.

Diesel Engine

16 Cylinder 710 G3B, 2 stroke, turbochargedafter cooled Fuel Efficient Engine Injection SystemDirect Unit Injector GovernorWoodward Compression Ratio- 16:1 Lube Oil Sump Capacity1073 Lts

Transmission

Electrical AC-AC 4 Traction motor ( 3 in parallel per bogie) SuspensionAxle hung / taper roller bearing


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TAS: TRACTION ASSEMBLY SHOP

TAS is the unit in which all the locomotive parts are assembled that include:

1. CP (Control Panel)2. Alternator

3. Traction Motors

4. 16 cylinder Diesel Engine

5. Master Control

6. Cab

7. Auxiliary Generator & Exciter

8. Governor

9. Crank Case Exhauster

10. Mechanical Assembly

1. Control PanelThe CP or the Control Panel (w.r.t. WG3A loco) consists of:

Control Switch Display Unit LED Panel Microprocessor based Control Unit Reverser BKT Valves Hooter CK1/CK2/CK3

The top portion of CP has sensors and relays connected to the microprocessor unit. The displayunit of microprocessor shows working condition of items in engine (electrical equipments apart

from engine). The LED Panel displays the overload, auxiliary generator failure, hot engine,

rectilinear fuse blown, etc. The battery ammeter shows the charging state of the batteries.

REV: Field wiring goes to reverser (REV) and hence it is used to control the polarity of thefield which in turn controls the direction of train.

BKT: It is a switch which in one direction is used to motor the loco while in other it is used for

dynamic braking.

Microprocessor based Control Unit: On-board microprocessors control engine speed, fuelinjection, and excitation of the alternator. These computers also interconnect with improved

systems to detect slipping or sliding of the driving wheels, producing faster correction and

improved adhesion. An additional function of the microprocessor is to monitor performance ofall locomotive systems, thereby increasing their reliability and making the correction of

problems easier.


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Why not feed direct DC to the traction motors via DC generators?

In a DC generator, the rotor is the coil. Alternators normally rotate the magnet, which is lighterthan the coil. Since alternators are built to spin the lighter component instead of the heavier one

they generally weigh only one-third as much as generators of the same capacity. DC generators,

in particular, require more maintenance because of wear on the parts that brush against oneanother in the commutator switch and the stress of rotating the heaviest component instead of thelightest. Also, when generators are run at higher speeds, electricity tends to arc, or jump the gap

separating metal parts. The arcing damages parts and could make generators hazardous to touch.

Alternators can run at high speeds without arcing problems.

3. TRACTION MOTOR

Its an electric motor providing the primary rotationaltorque of the engine, usually for conversion into linear

motion (traction).

Traction motors are used in electrically powered railvehicles such as electric multiple units and electric

locomotives, other electric vehicles such as electric

milk floats, elevators and conveyors as well as vehicles

with electrical transmission systems such as diesel-electric and electric hybrid vehicles. Traditionally,

these are DC series-wound motors, usually running on

approximately 600 volts.

4. 16 Cylinder Diesel Engine

It is an internal-combustion engine in which heat caused by air compression ignites the fuel. Atthe instant fuel is injected into a diesel engines combustion chambers, the air inside is hot

enough to ignite the fuel on contact. Diesel engines, therefore, do not need spark plugs, which

are required to ignite the air-fuel mixture in gasoline engines. The Diesel engine has 16cylinders. Pistons inside the cylinders are connected by rods to a crankshaft. As the pistons move

up and down in their cylinders, they cause the crankshaft to rotate. The crankshafts rotational

force is carried by a transmission to a drive shaft, which turns axles, causing mechanical output.

Eight 8V and four 2V Batteries are used in series to run a more powerful starter motor, which

turns the crankshaft to initiate ignition in a diesel engine for the first time.

5. Master Control

Its the unit that has the handles to regulate the speed of the loco as well as the direction of

motion. It has numbering from 0-9 and each increment causes rise in speed in forward direction.It can also be used to reverse the direction of motion by pushing the handle in the opposite sense.

It is present on the control desk of the cab.


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6. Cab

Its the drivers cabin with 2 control desks, the Control Panel (CP) and chairs for the driver. TheCab is at one end of the locomotive with limited visibility if the locomotive is not operated cab

forward. Each control desk has the Independent SA9 brake for braking of the engine alone and

Auto Brake A9 for the braking of the entire loco. It also has the following components: LED Panel Buttons of various engine LED lights (front and side) Automatic sand throw button (to prevent sliding of wheels on inclined tracks) Master Control Gauges to monitor booster air pressure and fuel & lube oil pressures. Speedometer Service Brakes (Independent and Auto brakes described above) Emergency Brake (Type of Air brake to halt the train in the distance nearly equal to the

length of the train, to be used only during an emergency)

7. Auxiliary Generator and Exciter

The Alternator has these two components. The exciter and the auxiliary generator consist of two

armatures on a single shaft. The auxiliary generator supplies a constant voltage of around 72Vfor supplying power to charge the battery for the control equipment and to power the locomotive

lights. The Exciter supplies excitation for the main generator.

Starting of Engine

The supply from the batteries is given to the exciter. The exciter has armature and field windings.

Hence it starts rotating as it receives the supply voltage. The Exciter is coupled with the rotor of

the alternator which in turn is connected with the propeller shaft. When the propeller rotates at aparticular rpm, the engine gets started. Its just like starting a bike. The kick must be powerful

enough to start its engine. Later the engine runs on diesel oil (fuel). As soon as the engine starts,

the auxiliary generator also coupled with the alternator starts charging the batteries. Its potentialis maintained at ~72V.

8. Governor

It is the device that has the following functions:

1. To control engine speed

2. Deliver fuel (Diesel oil) according to load

3. To mediate electrical demand and diesel engine output

9. Crank case exhauster

It is the device used to evacuate the diesel engine chamber.

10. Mechanical Assembly


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All mechanical parts on the engine apart from the above mentioned units may be grouped in this

category. It essentially consists of:

Base frame Wheels Air Brakes Batteries Sand Box Vacuum brakes Fuel tank (Loco fuel oil tank capacity is 3000L) etc

Ai r Braking System of Locomotives:

On a train, the brake shoes are pressed directly against the wheel rim. A compressor generates

air pressure that is stored in air tanks.

Air hoses connect the brakes on all the train cars into one system. Applying air pressure into the

system releases the brakes, and releasing air pressure from the system applies the brakes.

HARNESS SECTION

With the help of the harness board, we can have layout of wires which are required for control of

loco. If it were not there then will be great difficulty in connecting the diffrent wires.

There are three types of harness boards,

1. Group 1

2. Group 2(e.g. GroupWDG-3A)

3. Group 3

In terms of voltage level there the harness boards can be divided into two categories.

1. High voltage

2. Low voltage

BATTERY SECTION

IN THE LOCO batteries are used only for starting purpose.

Two types of the batteries are used:

1. Lead Acid Battery

2. Nickel Cadmium battery

LEAD ACID BATTERY


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Sulphuric acid (H2so4) of specific gravity 1.25 is used. There are 8 batteries 8v each; total 64v is required for a loco. Each battery has 2 cells of 2v each. Each battery is charged for 72 hours and discharge for 10 hours through grid

Through heat dissipation. After this again 10 hours charging is required.

After having completed this process the battery is ready for use.

In the loco the battery is charged through auxiliary circuit which is provided by alternator.

NICKEL CADMIUM BATTERY

This battery is called as no maintenance battery because no maintenance is required because of

absence of any acid part. The rating of this battery is 150A-H

BATTERY CHARGER

Charging of the Battery is done at 15 A and 70 V.

Rating of the charger used:

Input- 360-460 V.

LTS: LOCOMOTIVE TESTING SHOP

It is the shop where the final testing of the engine is performed before the engine is dispatched foruse by the Indian railways.

The important electricalinspections and tests performed are:

FIR Impulse Insulation Registering (IR) High Potential Test Battery Connection Digital I/O checking (for microprocessor control unit) Fuel pressure adjustment Engine Cranking Auxiliary Generator Check AC Voltage Check Temperature switch check Load cable connection and load test Loco Normalization test (In which load cable is disconnected) Traction Motor boot application


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DM Boot application Track test and dynamic brake checking Running operation Brake safety devices Static air pressure (SAP) test for motor cooling Rotary machine inspection Locomotive Brake Systems

a) Charging

b) Pressure gauges

c) Compressor governor

d) Main Reservoir Leakage

e) Reservoir Check Valve

f) Brake Pipe Leakage

g) Air Compressor Check

h) Auto brake valve

i) Brake Pipe Maintaining Feature

j) Independent Brake

k) Cut off Valve

l) Lead or Trail Selector

m) Dynamic Interlock

n) Brake Cylinder Leakage

o) Brake-in-two

p) Main Reservoir Safety Valve

q) Vigilance Control

r) Remote Control Locomotives


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AN OUTLINE OF LOCO TESTING:Electric locomotives must be tested at normal line voltage. A general outline of loco testing is asmentioned below. However, its a mere picture of whats actually done. The actual no. of tests is very

large and it was out of the scope of the training.1. Engine is brought to the shop LTS

2. its inspected properly for any visible locomotive errors.3. Fuel Oil tank is tested for leakage.

4. This is done by filling it with water.

5. Indene solution (0.68 kg in 1000L of water) is filled in expansion tank

6. Lube oil filling

7. Air compressor/expresser setting is tested

8. Crank shaft deletion and lube oil circulation tests are performed.

9. Initial working and temperature checking is done:

Lube oil pressure: 4-5 kg/cm

Fuel oil pressure: 3.5-4.5 kg/cm

10. Load Test:

All load connections are made Crank case vacuum is checked U tube water manometer is used to measure the pressure of fuel oil. At full load,

a) Lube oil pressure: 6.5-7.5 kg/cm

b) Fuel oil pressure: 2.8 kg/cm

c) Turbo Discharge pressure should be the same both in driver cab gauge and

Mercury manometer in testing centre.

d) Booster Air pressure: 1.6-1.6-1.79 kg/cm for 46"-52" DWM2 loco1.7-9.0-1.79 kg/cm for 52"-59" DWDG2 loco

e) Temperature of engine cooling water is 80C

11. Air Brake tests:

The Independent and auto brakes as well as the emergency brakes are tested. Also the brake pipe andbrake cylinders are tested for leakages. At the same time compressors are tested either by orifice testor by the time taken to charge the main reservoir from 0 KPa to 550.

INSULATION RESISTANCE AND HIGH-POTENTIAL TEST

CAUTION: Before making a high potential test, the insulation resistance should be checked with a 500Vmegger.Do not conduct high-potential test on a circuit with a megger reading of less than 1M as the circuitmay be damaged.

INSULATION RESISTANCE (NEW LOCOMOTIVE)

Have multi conductor plugs attached to the governor and tachometer generator. Open battery switch ,BS


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Open ground cut-switches GRCO1 & GRCO2 Disconnect the battery leads in the battery compartment then close the battery switch -BS. Close all switches and circuit breaker in the control compartment and on the control stand (or

gauge panel).

Move engine control switch ECS to RUN Position. Move reveres handled to forward or reverse position. Breaking switch must be in motoring.

Move main handle to 6th Notch position.

Remove EXCP, TRP PANEL CARDS. Tie all high- voltage terminal points together on theexcitation panel. These points are 34B,34T,34S,34A,34C,34,D,34E,34F34G,34F,36,R23 and40V.

Tie all control-Voltage terminal point together on the transition panel, voltage-regulator andengine control panel. On the engine-control panel, 34S and 34T are high-voltage points.

In the power circuit of rectifier unit, short AC terminal(R,Y &B) and DC terminal (GA11&GA2)Put jumper between AC and DC terminals(R & GA11).

Measure insulation resistance between blower motor terminal R-28 and locomotive frame. Measure insulation resistance (1 m ohm) between power circuit and locomotive frame.(The

braided shunt of a "P" or "s" Contractors is a convenient place to clamp megger lead).

Tie a jumper from the braided shunt of CK-1 to braided shunt of CK-2 & CK-3. Measure insulation resistance between control circuit and locomotive frame. Connect megger to aCK contactor and ground.

Measure insulation resistance between power and control circuit to be sure that they are not tiedtogether.

Before making a high potential test be sure that the indicated insulation resistance of itemHIGH-POTENTIAL TEST-POWER CIRCUIT:

Ground control circuit to locomotive frame. Short out load ammeter with hi-pot wire. Attach one terminal of high-potential transformer to locomotive frame and the other side to any

convenient point in the traction motor circuit such as the main contact of a P and S contactor.

Apply high potential:

New locomotive : Apply 2000V for one minute.Locomotive in service : Apply 1050 for one minute.

HIGH POTENTIAL TEST- CONTROL AND AUXILIARY CIRCUITS:

Check wiring and terminal boards. Correct loose connection and faulty insulation. Close all switches and breakers. Remove temporary ground. Short out the battery charging ammeter with high potential wire. Also short out Led panel

terminal with high potential wire.

Attach ungrounded side of high-potential transformer to main movable contact of CK contractor. Apply high potential of 680 for one minute. Open all switches, set main handle and Engine control switch(ECS) to idle .close

Ground cutout switches GRCO1 & 2 . Remove all ties on all control voltage terminal pointAnd insert back EXCP TRP & VRP panel cards. Remove all shorting/jumpers.


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Reconnect battery leads. Make sure that leads are connected correctly with respect to batterypolarity.

AUXILIARY AND ALARM CIRCUITS SEQUENCE AND RELAY SEQUENCE

CHECK:

PRELIMINARY:

Have all switches of battery switch open controller handles in off and idle and ECS switch in idle. Block CK1 ck2 ck3 contractors open with a 1/16 inch thick rubber sheet placed between contacts

with the arc chutes removed. Insulation must allowed sufficient movement of contact armature toopen and close interlocks.

Ring out train lines from coupler sockets to terminal boards. Charge locomotive air system with at list 70 PSI shop air. If locomotive has safety control use

foot pedal to hold safety control off and make a full independent application to keep safely

control suppressed.

Close battery switch BS.

Close master battery breaker MB1 and main control breaker and MB2.DIESEL ENGINE SPEED CONTROL SEQUENCE (Motoring Dynamic Breaking):

PERLIMINARY (MOTORING):

Close master battery breaker MB1 & main control breaker MB2.close master circuit breakersMCB_1 &2 close master fuel-pump breakers MFPB_1 &2 and fuel pump breaker FPB14.

Have main handle in idle and reverse handle in off the safety control relay DMR should beenergized.

Have M.U. stop button in the RUN position.SEQUENCE CHECK (MOTORING):

Move the main handle from idle to 8th notch .noting the operating of the operation of the dieselengine speed set relays.ESR1, ESR2, ESR3 and ESR4 at each notch.

With main handle in 6th notch keep (the switches MUSO) &2 in "STOP" position-diesel enginespeed set relay ESR4 should be the only relay energized. Reset MUSD & 2 in RUN position.

Open all miniature circuit breakers-MB, MB MCB1, MCB2. "DMR" should drop off. OpenMEPB1 2 and FPB.


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MAIN RECEIVING SUBSTATION (MRS)Substation generally consist of pump, DG sets, and control panels .The control panel is used to

Control the supply .It is the point from where load is monitored. Different parts of sub statio are as

follows :

Transformers control panels Bus coupler Relays circuit breaker Capacitor Capacitor bank Switch board attendant

DIFFRENT TYPES OF TRANSFORMERS USED IN DLW

1. Distribution transformer

2. Power transformer

3. Potential transformers

DISTRIBUTION TRANSFORMERS:

These transformers are used for the distribution purposes. They are basically step down transformers.

The load on the distribution transformer. The load on the distribution transformer varies over a wide

period of 24 hours. The primary of distribution transformer is always energized so core losses are

designed to have very low value of core losses.

MAIN CHARACTERSTICS OF DISTRIBUTION TRANSFORMERS:

1. Low core losses

2. Low on state losses

3. Good voltage regulation

4. Low leakage reactance

5. High day efficiency

The rating of different distribution transformers used in DLW are 150 KVA, 250 KVA,400 KVA,750KVA. These transformers are used according to the shop requirement or colony requirement.

POWER TRANSFORMER:

Power transformer are used at the sending and receiving end of a long transmission line for stepping

down and stepping up voltages.


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MAIN CHARACTERSTICS OF POWER TRANSFORMER:

1. Low losses at full load

2. Very poor voltage regulation

3. High full load efficiency

4. Low on status losses

5. Leakage reactance is variable

The power transformer which is used in DLW gets 33 KV supply from UPPCL and this supply is step

downed to 11 KV. This supply is fed to different feeders of DLW. The three phase transformer which is

used has following properties. Primary side i.e. HV side the winding are delta connected. Secondary side

i.e. LV side the winding are STAR connected.

POTENTIAL TRANSFORMER:

This is an instrument transformer which is used to measure the voltage of a line. Mostly they take record

of line voltage whether it is proper or not. In DLW it is used in control panels.

CONTROL PANEL

This unit controls the rating of the transformer. From here one can control the switching of transformer

And also the charging of transmission line. From control panel the DC set is also controlled.800KW and

1700KW DC sets are used in DLW as an alternate source of supply. There are 25 control panels in the

MRS each of capacity 350 MVA. With each panel there is wattmeter, ammeter, voltmeter attached.

BUSCOUPLER

This is used to couple two buses incomer and outgoing one.bus coupler is the main device so it is

generally protected from overloading. The maintenance of this device is not easy so for maintenance of

this duplicate bus coupler is used.

RELAYS AND CIRCUIT BREAKERS

RELAYS:

Relays and circuit breaker are used for the protection of the power system from different faults which are

occurring in the power system. A relay is simple electromechanical switch made up with electromagnet

and set of contacts. Relays are found i all sorts of devices.

The relays which are used in the substation are fol lows,

1. over current relay

2. under voltage relay

3. Different relays


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4. Directional relay (Reverse power relay).This relay is used for the protection of bus coupler because it

senses the direction of power flow.

These relay does not anticipate the fault but come in to action when the fault has happened .When faults

occur it sends a trip a signal to circuit breaker finally breaks the circuit and isolates the faulty part of

power system.

CIRCUIT BREAKERS:

Circuit breaker, electrical device that cuts off the electric current through a circuit under abnormalconditions. The most familiar household circuit breaker protect circuit, Against overloading or

over heating to prevent and electrical shock.

Circuit breaker also provides protection against short circuits. A short circuit is caused by acontact between the neutral and grounded, side of the electrical line and the live side of the line.

Defective insulation or other parts can cause shorts. Shorts circuit offer very low resistance to

current which allows large current to flow through the circuit sometimes melting the wires or

causing a fire. Circuit breakers in the live side of the electrical line can stop short circuits bycutting connection when the current gets too high.

Circuit breaker is used to break the circuit at a point in transmission .The rating of circuit breakerdepends on the current handled by transmission network .This also depends on transient response

of the system .some of circuit breaker are microprocessor based. They automatically controlled

by closed loop system.

Circuit breaker that deals with high level of current especially direct current, have methods ofgetting rid of the energy in the arc and stopping the current. In oil breakers the design of the

circuit breaker forces the arc of broken circuit through a sealed container of oil or gases .The arc

heats the oil around it. The hot oil begins to circulate in the tank, carrying heat and energy away

from the arc. Air-blast circuit breaks send the arc through compressed air, which is immediately

released to the outside carrying the heat and energy of the arc with it.

TYPES OF CIRCUIT BREAKERS USED IN DLW:1. Oil circuit breaker

2. Air circuit breaker microprocessor based

3. Vacuum circuit breaker of maintenance less circuit breaker

CAPACITOR BANK

In the electrical system the power factor plays very important role because by improving the power factor

one can losses and tariff. Generally power factor should not be brought below 0.8 for industrial loads.


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The main reason for the reduction of the power factor is due inductive loads primarily induction machines

which is low power factor machine. It reduces power factor because it draws huge demagnetizing current

from supply. To improve factor capacitor banks are placed in parallel with power supply.

REASONS FOR IMPROVEMENT OF POWER FACTOR:

1. Reduced losses

2. Reactive power decreases active power increases

3. Reduction in tariff

4. Efficiency of machines increases

ADVANTAGES OF USING CAPACITOR BANK:

1. Easy to increase the capacity of bank

2. Reliability of the system is high

3. Controlling the bank is easy4. Maintenance is easy

5. No flow of circuiting current

In DLW, 600 KVAR capacitor bank is used for the improvement of power factor.


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MAINTENANCE SERVICE SHOP

(MSS)

WINDING SHOP

In this shop motor winding, taping, wiring of motor is done.

MATERIAL COMMONLY USED IN WINDING:

1. Film Leatheriod paper: The leatheriod paper covered with film layer is called filmleatheriod paper. It is available in sheets and weight having thickness of 5 mile to 15

mils. it is costly and better than leatheriod paper. it is also used for insulating the slots of

motor.

2. Empire cloth: it is yellow color cloth having a layer of wax to protect it from moisture. Itis available in meters having the width of one meter with thickness of 7 mils to 10 mils. It

is highly flexible, good mechanical and dielectric strength. It is also non-hydroscope. It is

used for insulating the slots of the motor.

3. Pressphan Paper: it is also used for insulating the slots of the motor. Its surfaces lightlyglazed and available in thickness of 3 mils and 5 mils 10 mils. it is in brown in color.

4. Micanite: it is a combination of soft mica, shellac and adhesive pasted on paper or clothknown as micanite paper or micanite cloth.ir is available in thickness of 2 to 6 mm in the

Winding

ShopElectronics

lab

Meter

LabO.H.


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form of sheets. it has good dielectric strength and can withstand, very high voltage before

using it is required some preheating. it is used in high voltage machines.

5. Fiber: it is coffee brown color sheets having thickness of 1 to 15 mm. it is used formaking wedges for covering the coils in the slots and makes bobbins, panel board etc.

6. Cotton Tape: it is white cotton cloth having width of 12, 20, and 25mm and length of 25,50 meters rolls.

7. Empire Tape: it is made of empire cloth having length of 12, 20, and 25mm and lengthof 25 and 50 meters rolls. It is not affected by moisture. It is also used for taping the coils.

8. Glass tape: made of glass and cotton. Used for taping the high temperature machine.9. Solder, soldering flux, winding thread: solder is made of with lead and tin. Soldering

flux is helping agent during soldering, it also prevent oxidation. Winding thread is used

for winding the coils and available in balls.

Data during dismantling the winding

Number of slots Number of coils Types of winding Number of poles Number of coil groups Number of coils per group Coil pitch Group connection Phase connection

Data after dismantling the Winding

Size of winding Size of coil Number of turns per coil Weight of coil Type of insulation


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SHAPE OF COIL:

Mush Coil: A coil having both active sides is equal in shape and size is calledmush coil. This coil is prepared on single formal in the shape of V or U. these

types of coils are commonly used in the winding.

Skew coil: A coil having one active side bigger than other is called skew coil.These coils are providing more cooling for winding. These types of coil are

mostly used in higher capacity machines.

Diamond Coil: First the coil is prepared and then its both sides pulled up to giveproper shape.

Involutes coil: This types of coil made of with strips and bars. it is used whereless space is available.

Combination Coil: Combination of diamond and involutes coil is calledcombination coil. This coil has one side like diamond and other side like involutes

type coil.

Types of winding

Single layers winding Double layers winding Concentrated winding Distributed winding Whole coil winding Half coil winding Flat loop winding Chain winding

Meter section

Calibration of meter is done and the fault in the meter is detected.

Calibration

Error detection of any meter is called calibration. Calibration is a comparison between

measurements-one of known magnitude or correctness made or set with one device andanother measurement made in as similar a way as possible with a second device. The

device with the known or assigned correctness is called the standard. The second device

is the unit under test (UUT), test instrument (TI).

RTD (Resistance temperature Detector): it is a type of temperature sensor .its range is 0-

400 C. it is k type.


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Thermocouple:

Two different type of metal are join at one end is called thermocouple .it shows partial

different.

Substandard Meter:

In this type of meter there is no any error. Error tends to zero.

ELECTRONICS LAB

In this lab only repairing of control panel, PCB, transistor checking, IC checking is done.

Rectifiers/Inverters

The output from the main alternator is AC but it can be used in a locomotive with either DC or

AC traction motors. DC motors were the traditional type used for many years but, in the last 10

years, AC motors have become standard for new locomotives. They are cheaper to build and

cost less to maintain and, with electronic management can be very finely controlled. To see

more on the difference between DC and AC traction technology.

To convert the AC output from the main alternator to DC, rectifiers are required. If the motors

are DC, the output from the rectifiers is used directly. If the motors are AC, the DC output from

the rectifiers is converted to 3-phase AC for the traction motors.

QT-200(PCB DIAGNOSTIC AND FUNCTIONAL TEST SYSTEM)

Qmax is a global leader in the field of Automated Test

Equipment PCB Repair, Diagnostic and Board Functional

Test Systems. TheQT-200 Mixed Signal Functional Test

System is a proven model being used by thousands ofusers

world over for varied applications.QT-200 Can effectively

test Digital, Analog and Mixed Technology ICs in In-Circuit,

as wired condition and gives clear PASS-FAIL results.

Hybrids, ASICs and house-coded ICs can be checked using

QSM signature method. Optional IDDE software makes new

device test program generation easy with graphical user interface.


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OVERHAULING SECTION

Induction motor

The most common motors used in industrial motion control systems, as well as inmain powered home appliances.

Advantage of AC induction motor:1. Simple and rugged design,

2. low-cost,

3. Low maintenance and

4. Direct connection to an AC power source.

BASIC CONSTRUCTION AND OPERATING PRINCIPLE

An AC induction motor has a fixed outer portion, called the stator and a rotor thatspins inside with a carefully engineered air gap between the two.

The rotating magnetic field is created naturally in the stator because of the natureof the supply.

Formula:

The relation between supply frequency f, the no of poles p, and the synchronousspeed is Ns = 120f /p.

Rotor speed: Nr= Ns (1s) , where s is the slip. A synchronous motor always runs at synchronous speed with 0% slip.

TELEPHONE EXCHANGE

There is BSNL network inside the D.L.W Provides telephone connection to D.L.W administration block and their local colony area. The exchange is design to perform satisfactory for a line loop resistance of 1000ohm for

each subscriber


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The local loop is the physical layer or circuits that connect from demarcation point ofcustomer premise to the edge of telecommunication service providers network.

The exchange work of D.C. voltage supply of 50V obtained from battery set which areparallel connected through the charger which operate on 230V A.C. supply

The voltage required when two subscriber talk is 12VIMPORTANT PART IN EXCHANGE

1. BATERRY CHARGER:Charger operates 230 V A.C. supplied to it and provided to 48-50V D.C. to exchange.

Charger is attached with battery in parallel. When power supply cut then charger connect

with battery and start working on battery.

2. BATTERY:In the exchange, batteries are used to operate it. The multiple batteries connected in

parallel with each other as soon as electricity goes off then exchange works with these

battreis.Battery which used for exchange is Lead acid battery which can be

Rechargeable.

LEAD ACID BATTERY:

Invented in 1859, are the oldest type of rechargeable battery.CONSTRUCTION

In complete battery there is positive and negative palate. All negative plate are joinedwith the help of solder at the terminal post. This is called negative terminal and vice-

versa positive terminal for positive plate.

The negative and positive plate are kept in such a manner that every positive plate placedin between two negative plates. In this way the no. of negative plate is used more than

positive plate. Positive and negative plates are kept nary closed to each other.

There is doubt of mixing of the plates thats why separators are used between them woodrubber, glass, ebonite to keep them in distance. There are 4 batteries of 12V each; total 50V voltage is required for exchange. Each

battery has 6 cells each of 2.15V each.


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Electrochemistry: when load is given, current flows through highest side H2SO4 burstand by this action H ion goes to positive plate(PbO2) and SO4

--ions goes to negative

plate(Pb). Then the equation formed at

Positive plate:PbO2 + H2 + H2SO4 => PbSO4 + H2O

(Lead sulphate)

Negative plate:Pb + SO4 => PbSO4 (Lead sulphate)

INTERMEDIATE DITRIBUTION FRAME

A frame that(a) Cross-connect the user cable media to individual user line circuits and(b)May serve as a distribution point for a multi pair cable from the main distribution

frame (M.D.F) to individual cable connected to equipment area remote from these

frame.

The cable that come out from exchange line are installed in the crown type on the wallare called I.D.F.

MAIN DITRIBUTION FRAME

It is signal distribution frame for connecting equipment cables and subscriber carrierequipment.

Termination point within the local exchange. Exchange equipment and terminations of local loops are connected by jumper wire at the

MDF.

The fuse is attached at the back side of the tag block for safety. As when thundering orvibration occurs the fuse gets blow of making the circuits break and thus we can prevent

further damages.


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JUMPER WIRE

Each jumper is a twisted pair. Twisted pairs is cabling is the form of

wiring in which two conductors are

twisted together for the purpose of

Cancelling out electromagnetic

interface (EMI) from external source

,or twisted pair is also used to avoid

unwanted noise from the signal.

ELCTROMAGNETIC INTERFACE (EMI)

It is an disturbance that affect an electric circuit due to either electromagneticradiation emitted from an external source.

The disturbance may interrupt, obstruct, or otherwise degrade or limit theeffective performance of the circuit.

In balance pair operation, the two wires carry equal and opposite signal and thedestination detects the difference between the two.

DISTRIBUTION POLE:

DP is much nearer to the consumer where it is easier to take cable from the

consumer.

DISTRIBUTION BOARD

In telecommunication, a distribution boardis a passive device which terminatescable, alloying arbitrary interconnection to be made.

It is box type boards in which cables pad are distributed according to the no.which are provided to the nearer distribution.

D.C. is installed after the certain interval of the distance make a properdistribution of the cable easier to reach the consumer.


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Distribution board

FAULTS

Line contact: It means that the drop wire has connected either with pole are tree and abusy tone is obtained when we dial the number.

Line earth: It means the wire which is broken is in touch with a pole or earth and there asoft humid sound is coming when we dial the number.

Line disc: The wire has been broken down.


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dlw report

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