1. CHAPTER 1
CENTRAL ELECTRONICS LIMITED
1. COMPANY PROFILE
1.1. ORGANISATION STRUCTURE OF CEL
Fig.1.1.Organization structure of CEL
1
CHAIRMAN &
MANAGING DIRECTOR
GENERAL
MANAGER
(CP & HRD)
Jt. GENERAL
MANAGER
(FINANCE)
EXECUTIVE
DIRECTOR
(OPERATIONS)
AGM
(QUALITY
ASSURANCE)
Jt. GENERAL
MANAGER
(MATERIALS
MANAGEMENT)
GENERAL
MANAGER
(PROJECT
MANAGEMENT)
GENERAL
MANAGER
(SYSTEMS)
Jt. GENERAL
MANAGER
(MICROWAVE)
GENERAL
MANAGER
(SPV)
Jt.GM
(CERAMICS)
Jt. GENERAL
MANAGER
( R & D )
AGM
(FERRITE)
2. 1.2. DIVISIONS OF CEL
Five business groups handle the total commercial operations of the Company. These
are as follows:
SOLAR PHOTOVOLTAIC GROUP (SPV):
CEL, backed by an integrated production facility, has opened up new horizons in the field
of Solar Photovoltaic. It fulfills the various demands from rural & urban areas, thus,
harnessing the solar energy. The products of this division are Solar Cells, Modules and
systems, which serve the industrial needs of Railway Signaling, Microwave Repeaters,
Defense equipments, Obstruction warning lights at airports, etc. and rural needs such as
pumping systems for irrigation, street lighting systems, solar lanterns and rural
telecommunications.
ELECTRONIC SYSTEMS GROUP (ESG):
The Company is a pioneer in manufacturing of Railway Signaling and Safety
Equipments. It manufactures Axle Counters, Railway Level Crossing Warning System,
and Solid State Interlocking System for Railways. The other products of this division
include Electronic Switching System, Cathodic Protection System for underground
pipelines and VSAT.
COMPONENTS GROUP:
A large range of products is manufactured here using state-of-art technologies to meet the
requirements of communications, defense, consumer and industrial sectors. It is divided
into three sub departments. Their products and applications are as follows:
Professional Ferrites:
This department manufactures different types of ferrite cores for high frequency
applications. The different types of cores manufactured are Pot cores, E, U, I, RM,
torroids etc. These are called professional because they require highly sophisticated
techniques for their manufacture and give a superior performance. The various
applications of ferrite cores include TV sets, Communication equipments, computers,
electronic ballasts, switch mode power supplies (SMPS) and Microwave equipments.
2
3. Electronic Ceramics:
This department manufactures piezo-electric transducer elements, high temperature
crucibles, high speed bearings and other alumina products. These products are used in
Defense ammunitions, Ultrasonic cleaners, Buzzers, Sonars, Gas Lighters, Automobiles,
etc.
Microwave Electronics:
This department manufactures microwave components such as Phase Shifters used in
Radars, Direction Finding Systems, Frequency Correlators, Antennas, etc.
1.3. PRODUCTS of CEL
The organization manufactures different products that can be classified according to the
divisions of CEL as follows:
Solar Photovoltaic Group:
• Solar Cells/Modules
• Solar Lantern
• Street Light System
• Home Light System
• Water Pumping System
Electronic Systems Group:
• Single / Multiple Entry / Exit Axle counters
• Universal Axle counters
• Block proving system
• Railway Level Crossing Warning system
• Solid State Interlocking System for Railways
• Cathodic Protection system
• Very Small Aperture Terminal (VSAT)
• Electronic Switching Equipments
3
4. Components Group:
• Different types of ferrite cores like Pot, RM, E, U, I, etc
• Piezoelectric transducer elements
• Special Bearings used in Heavy Water Plants
• Microwave Ferrite Phase shifters
• Direction Finding Systems
1.4. NATION’S PIONEER & WORLD LEADER IN SOLAR
PHOTOVOLTAIC:
In an era of growing energy needs and rising concern for environment, solar energy, the
abundant and pollution free non-conventional energy source, offers the best alternative
solution.
CEL, with its commitment to harness the solar energy, has opened up new vistas in the
field of solar photovoltaic. CEL is the poignant and the largest producer of solar
photovoltaic. Backed by an integrated production facility, CEL has made accumulative
supply of over 1.5 lakhs SPV systems (20 MW) spread over 28 different types, covering
both rural and industrial applications. The company has not only given a fillip to the
Indian SPV market but also exported products to Indonesia, Bhutan, Bangladesh,
Egypt, Cuba, Nepal, Mali, Columbia and Costa Rica.
CEL has successfully transferred technology for manufacturing SPV Modules and
Systems to Rajasthan Electronics & Instruments Ltd. India in 1985 and very recently to
Scientific Studies and Research Center (SSRC), Syria in May 1997. This is the first case
of SPV Technology Export from the Developing World.
CEL’s SPV Modules conform to the international specifications – JPL Block V and IEC
specification no. CEI / IEC 61215. CEL SPV Modules were certified by European Solar
Test Installations (ESTI), JRC, Ispra, Italy.
4
5. 1.5. INNOVATIVE ELECTRONIC SYSTEMS
Signaling & Safety Systems for the Indian Railways:
CEL is the pioneer Public Sector Company supplying Railway Signaling and Safety
equipments to Indian Railways. CEL continually identifies new requirements of the
Railways and develops / manufactures the same in association with Research, Design
and Standards Organization (RDSO) and Railway Board. The Company is currently
engaged in development of Digital Axle Counter in association with RDSO and
Department of Scientific Industrial Research (DSIR).
The product is undergoing extensive field trials in different zones of Indian Railways and
software validation is under progress. The product is expected to be deployed in Indian
Railway’s Signalling network in large numbers by the end of year 2002.
Cathodic Protection Systems:
CEL supplies Automatic Cathodic Protection Systems for the protection of oil / gas
pipelines to organizations like Indian Oil Corporation, ONGC and GAIL. The Company
supplies different types of Cathodic Protection Systems operating with solar photovoltaic
or thermoelectric power sources or operating on grid supply.
1.6. QUALITY POLICY OF CEL
The complete manufacturing operation, marketing and installation services of the
company is certified under ISO 9002 : 1994. The company has enunciated the following
quality policy to meet customer needs and expectations through supply of quality
products and services.
“CEL is committed to strive for leadership in the product marketed by the way of
continuous improvements in the quality of its products and services and meeting the
consumers needs in time and every time at a competitive price”. These shall be
achieved through continuous upgrading of technology and process improvement by
involving all the employees, vendors, dealers and customers.
5
6. “Quality is our basic business principle.”
CHAPTER 2
2. WORKING PRINCIPLE OF UNIVERSAL AXLE COUNTER FOR
RAILWAYS:
2.1. INTRODUCTION:
Axle counters were developed as a substitute for track circuiting. Initially axle counters
were imported from Germany to gain experience and to evaluate their suitability for
adoption on Indian Railways. Having gained acceptability for introduction on a wide
scale on Indian Railways, it was considered to take up indigenous development of axle
counters, which was taken up in collaboration with IIT, Delhi and DOE. Two models of
axle counters known as single entry/exit axle counter and multi entry/exit axle counters
emerged and after extensive laboratory and field trails under various conditions, the
design was finalized and commercialized through private sector as well as public sector.
Based on the feedback from field, a new axle counter has been developed by RDSO,
known as “UNIVERSAL AXLE COUNTER”.
NEED FOR AXLE COUNTERS:
The track circuits are considered as the vital components of signaling system to achieve
safety of train operations. Various Accident Enquiry Committees have recommended to
bring more and more tracks under track circuiting to safeguard against reception of trains
on occupied lines. The track circuiting could not achieve desired progress due to virtual
scarcity of wooden sleepers, prohibitive cost and environmental consciousness in the
country and the world at large. Availability of concrete sleepers have solved the problem
to some extent but track circuiting on loop lines, points and crossings still suffers for
want of adequate supply and insertion of concrete sleepers.
ADVANTAGES:
The advantages of Axle Counter over a conventional track circuit are:
6
7. (i) It does not require wooden sleepers (where concrete sleepers are not
available) except for short track circuits to suppress the counts due to
movement of insulated trolleys.
(ii) An Axle Counter System can cover a very long section of up to 15 km as
compared to 750 meters of maximum length of operation of conventional
track circuit.
(iii) It does not get affected either by flooding of track or poor maintenance of
tracks unlike track circuits, which is highly susceptible to these conditions.
(iv) It does not require insulating joints, thus, rails can be continuously welded.
This reduces track maintenance cost, lower wear and tear of tracks and
vehicles and to increase traveling comfort.
APPLICATIONS:
Axle counters are finding more and more uses on modern safety signaling systems in the
railways. These are being used presently for the following applications:
(i) Monitoring of berthing tracks in station areas and yards.
(ii) Monitoring of point zones in station areas and yards.
(iii) Automatic signaling systems.
(iv) Block section monitoring (between stations) through axle counters using
multiplexers with cable or radio communication (18 GHz).
(v) Level crossing warning system.
7
8. 2.2. FLOW CHART FOR MANUFACTURING OF AXLE COUNTER
Fabrication Electronic Components
Raw Materials
PCB
Rejected Accepted
Rejected Accepted
Mechanical
Components
Rejected Accepted
8
WAVE SOLDERING
CLEANING
INSPECTION
INSPECTION
SHIPMENT
COMPONENT MOUNTING
INSPECTION
CABINET FABRICATION
MECHANICAL FITTING
INSPECTION
CARD TESTING
SYSTEM TESTING
REWORK
STATION
LACQUERING
CABINET WIRING
SYSTEM INTEGRATION
9. Fig.2.2.Flow chart for manufacturing of axle counter
2.3. PRINCIPLE OF WORKING:
Signal aspect for train movement is controlled based on clear or occupied status of the
track section. If a train occupies the track section, signal at the entry point of the section
is made RED and the next train is stopped from entering into the section. When the track
section is clear the signal is made GREEN and the train is allowed to proceed into the
section. The clear or occupied condition of the track section is decided by Axle Counter
by counting the number of axles of train at entry and exit points of the section. The axle
counter compares the IN and OUT counts and in case of count equality TRACK CLEAR
signal is given. In all other conditions TRACK OCCUPIED signal is given.
Signal Signal
R1 R2 Railway Track R3 R4
T1 T2 T3 T4
Entry Point Track Section Exit Point
Signal Control
Relay Output
Cable
Cable
Fig.2.3. Block diagram of axle counter installation
9
EVALUATOR
10. 2.4. BRIEF DESCRIPTION:
The Axle Counter is an electronic device and the complete system consists of:
(i) Track mounting and trackside equipment.
(ii) Transmission media between trackside equipment and central evaluator.
(iii) Central evaluator with EV relays and SUP relays as its output.
(iv) Reset box.
(v) Line verification box.
Track mountings and track side equipments:
The track mounting equipment consists of a pair of transmitter and receiver coils housed
in specially designed housings, which are fixed to flange of a rail section by means of
suitable rail clamps using bolts and nuts. Each detection point has two sets of such tracks
devices mounted on same rail with a fixed stagger between them. The two transmitter
coils of a detection point are connected in series to 5 kHz oscillators housed in electronic
junction box which is installed in a location box by the side of the track. The output of
two receiver coils of a detection point serve as inputs to two receivers amplifiers housed
in the same electronic junction box through cables which are part of the track mounting
equipment. Electronic junction box is powered by 24 V DC supply.
Transmission media between trackside equipment and central
evaluator:
The connection between trackside equipment and central evaluator is made using
balanced twin twisted quad cables of specification IRS: TC/41/90. The output of
electronic junction box and input of central evaluator are matched for an impedance of
about 180 ohms at 5 kHz.
There is attenuation of signal from electronic junction box to central evaluator, which
limits the length of the cable. Other media such as optic fiber and wireless system may
10
11. also be used in place of cable by incorporating appropriate interfacing equipment at
transmitting and receiving ends.
Central evaluators with EV relay and SUP relay as its output:
The signals received from electronic junction boxes are processed in the central evaluator
first by analog circuits and then by digital circuits to produce suitable output in terms of
picking up or dropping of EV and SUP relays. The Dip’s generated by wheels as they
pass over the track devices installed at detection points, after they get processed,
generate count pulses in a fail safe manner.
These pulses are identified as ‘IN COUNTS’ or ‘OUT COUNTS’ depending on the
direction of movement of vehicles over the monitored section. The counts are also
displayed through the 7-segment display on the front panel of the evaluator. The display
unit is useful in fault localization and initial and periodical adjustments.
The evaluator is provided with its own power supply unit known as DC – DC converter
mounted in the same rack and requires 24 V DC supply for its operation. The output of
the EV and SUP relays is used to indicate “TRACK CLEARED” or “TRACK
OCCUPIED” conditions.
Reset Box:
This equipment is installed in the station master’s room to enable resetting of central
evaluator in case of failure of system after observing prescribed procedure. The reset unit
consists of a RESET key (which gets actuated after inserting, turning and pressing), the
counter and 3 LED indications (Red, Yellow and Green). This unit requires 24 V DC
supply for its operation. This unit functions in conjunction with the line verification box.
Line Verification Box:
This box is required to be kept near monitored track portion outside Station Master’s
(SM) office for achieving co-operative feature. This is a box consisting of a lock with a
key fixed inside. The lock gets actuated only when the key is inserted, turned and
pressed. Whenever there is a failure of axle counter, SM will depute his ASM/Switchman
11
12. to verify whether the track section controlled by axle counter is clear or not.
ASM/Switchman after verification of the track, if found clear, will report to SM who in
turn will hand over the key of line verification box for operation.
TYPE OF SYSTEMS:
There are four types of system used in the Indian Railways. They are named below :
(i) One Device (1-D) System.
(ii) Two Device (2-D) System.
(iii) Three Devices (3-D) System.
(iv) Four Devices (4-D) System.
1-D System:
In this system, there is a common detection point at entry and exit point of monitored
section. This system is useful for monitoring the berthing track of terminal yard. A train
after passing the detection point generates pulses equal to axles in it and these pulses are
counted and stored by the evaluator as ‘IN COUNTS’.
At the time of exit of train, the same detection point will be encountered and it generates
the same number of pulses as that during the entry. These pulses are counted and
recorded as ‘OUT COUNTS’ by the evaluator. When the IN COUNTS and OUT
COUNTS are equal, the system gives a “Track clear” indication; otherwise it gives the
“Track occupied” indication.
2-D System:
The principle of working of this system is similar to 1-D System except that in this
system there are two detection points, one at each end of the monitored section. This
system is useful for providing track circuiting on berthing track.
3-D System:
In this system, there are three detection points. The principle of working of this system is
similar to 2-D system. This system is useful for providing track circuitry on points,
crossings and sidings.
4-D System:
In this system, there are four detection points. The principle of working of this system is
similar to 2-D system. The system is useful for providing track circuiting on branch lines,
12
13. sidings and points and diamond crossings. The design of 4-D system is such that it can be
converted into a 2-D system or a 3-D system and vice–versa.
2.5. SPECIFICATIONS:
Universal Axle Counter System mainly comprises of following
equipments:
Table 2.5. Universal Axle Counter Components
S.NO. Descriptions Quantity
1. Rack, ACS-55/56/57 (Common type for all
models)
1 Nos.
2. Evaluator EV – 542 / 543 / 544 1 Nos.
3. DC-DC converter (inside Evaluator only as 10th
Card)
1 Nos.
4. Electronic Junction for 2D system (ACS-55-2D) 2 Nos.
5. Box , JB-533 for 3D system (ACS-56-3D) 3 Nos.
6. For 4D system (ACS-57-4D) 4 Nos.
7. Reset box RB – 257B 1 Nos.
8. Track Device for a 2D system (ACS-55-2D) 2 Nos.
9.
Assembly for a 3D system (ACS-56-3D) 3 Nos.
10. TR-556 for a 4D system (ACS-57-4D) 4 Nos.
11. Line verification box LV – 261 1 Nos.
Table 2.5.1 Universal Axle Counter Components Specification
S.NO. Parameter Specifications
1. No. of Detection Points ACS-55 / 56 / 57 2 / 3 / 4
2. Maximum Train Speed 200 kmph
3. Counting Capacity 1023
4. Max. Line Attenuation (over cable) 20 dB
5. Signal Input (5 KHz) sinusoidal Min. 150 mv.rms Max.
1500 mv.rms
6. Relay Drive Voltage for 1000 ohm
Shelf type 4F / 4B relay or Q Style
Plug in Relay 1000 ohm, 4F / 4B
>10 V
13
14. Power Requirement:
Powers required by various units are as follows:
DC – DC Converter 1.5 Amp max.
24 V (-10% to +20%)
Evaluator 24 V 1.5 Amps
(21.6 – 28.8 V DC)
Junction Box 24 V < 250 mA
(21.6 – 28.8 V DC)
Reset Box 24 V 500 mA
(21.6 – 28.8 V DC) (Only when reset key is pressed)
Environmental Conditions:
Relative Humidity 95 % - 98% Non-Condensing
Temperature range:
Universal Evaluator 0 to + 60 ˚C
Junction Box & Track Devices 0 to + 70 ˚C
PHYSICAL CHARACTERISTICS:
The approximate dimensions and weights of various units of Universal Axle Counter are
given as follows:
Table 2.5.2 Approximate dimensions and weights of various units
Name of UNIT WIDTH
(mm)
DEPTH
(mm)
HEIGHT
(mm)
WEIGHT
(kg)
RACK
SINGLE 570 650 1065 70
DOUBLE 600 650 1460 100
EVALUATOR 482 439 310 21
JUNCTION BOX 208 280 170 5
RESET BOX 255 175 115 2.3
14
15. TRACK DEVICE
ASSEMBLY
515 330 170 15
LINE VERIFICATION
BOX 150 135 80 1.20
Colour:
The rack is painted in a combination of light and dark grey colours. Evaluator, Junction
box and Reset box are also painted in the same colour combination. The track devices are
painted in black colour.
.
IDENTIFICATION:
Rack:
The identification label of the rack is put at the left hand top on the front side of the rack
with inscription.
a) For a 2D system Universal axle Counter, ACS – 55 with EV – 542 Evaluator.
b) For a 3D Universal Axle Counter System, ACS – 56 with EV – 543 Evaluator.
c) For a 4D Universal Axle Counter System, ACS – 57 with EV - 544 Evaluator.
The serial no. label is mounted on the right hand top side of the rack at the back.
Evaluator:
The label “Evaluator, EV - 542”, “EV - 543” or “EV - 544”, for a 2D, 3D or a 4D system
respectively is marked on the front side of the evaluator. The serial no. label is on the
back side.
Junction Box:
On the top (front) of the Junction Box the label “JUNCTION BOX, (JB-533)” given
whiles the serial no. label is on the back plate.
Reset Box:
The label “RB – 257B” is given on the front side. The Sr. No. label is on the back side.
Line Verification Box:
The label “LINE VERIFICATION BOX, LV - 261” is put on the front side and the Sr.
No. label is on the right side cover.
15
16. Track Devices:
Labels indicating the Tx and Rx coil of the Track Devices are given on each track
transducer.
DC – DC Converter:
It is the 10th
Card Module inside the Evaluator and it is marked as “POWER SUPPLY”.
CHAPTER 3
DESCRIPTION OF VARIOUS MODULES OF AXLE COUNTER
SYSTEM:
1. EVALUATOR :
The Evaluator consists of 10 PCB modules. The interconnections between the various
PCB cards are made with the help of a motherboard. The polarization arrangement (to
avoid wrong insertion of modules) is provided on the aluminum modular sheets in
each. Hence it is important to ensure correct fitting of modular shield in each card. In
the Universal Axle Counter System manufactured by Central Electronics Limited,
relevant card number has been number punched for easy identification to ensure
correct fitting of modular shields. A brief description of each P.C. assembly is given
below.
(a) Attenuator/Amplifier & Rectifier Card (Card no. 1) :
This is a double sided PCB (Size: 225mm X 275mm). It contains four identical
channels, each comprising of a 5 kHz high pass filter, a line matching transformer,
attenuator pads, a two stage amplifier and a full wave rectifier. The output of each
channel can be set precisely by means of a lockable shaft potentiometer mounted at the
front end of the PCB module. Typical output is 300 mv (P-P) or 105-mv rms.
(b)Attenuator/Amplifier & Rectifier Card (Card no. 2) :
This is a double sided PCB (Size: 225mm X 275mm). It contains four identical channels,
each comprising of a 5 kHz high pass filter, a line matching transformer, attenuator pads,
a two stage amplifier and a full wave rectifier. The output of each channel can be set
precisely by means of a lockable shaft potentiometer mounted at the front end of the PCB
module. Typical output is 300 mv (P-P) or 105-mv rms.
16
17. For 1D and 2D Systems, there will be one such card (Card no. 1) while for 3D and 4D
Systems, the evaluator will have two nos. of such cards (Card nos. 1 & 2).
(c) Pulse Shaper Card (Card no. 3) :
This is a double sided PCB (Size: 225mm X 275mm). It contains four identical channels,
each consisting of a low pass filter, a Schmitt trigger, an impulse time filter and a 10 V to
5 V level converter. The outputs of these channels are TTL compatible. In addition to
above, each channel comprises of a Trolley Suppression Circuit.
(d)Pulse Shaper Card (Card no. 4) :
This is a double sided PCB (Size: 225mm X 275mm). It contains four identical channels,
each consisting of a low pass filter, a Schmitt trigger, an impulse time filter and a 10 V to
5 V level converter. The outputs of these channels are TTL compatible. In addition to
above, each channel comprises of a Trolley Suppression Circuit.
For 1D and 2D Systems, there will be one such card (Card no. 3) while for 3D and 4D
Systems, the evaluator will have two nos. of such cards (Card nos. 3 & 4).
(e) Logic – I (Card no. 5) :
This is a double sided PCB (Size: 225mm X 275mm). This card generates ‘IN
COUNTS’ and ‘OUT COUNTS’, depending upon the direction of the train
movement, due to the dips caused form the track transducers E, F, G, H. In addition
to main count pulses, duplicate in count and out count pulses are also generated here
for supervision purpose. The ‘IN COUNT’, ‘OUT COUNT’, ‘Duplicate In count’ and
‘Duplicate Out count’ pulses are fed separately to different combiner gates housed in
card 6 (Logic II) and thereafter fed to the counter card (Card 7) for further processing.
As E, F, G, H channel inputs are used only in case of 3D or 4D Systems, card 5 will
be used only with the 3D and 4D Evaluators.
(f) Logic – II (Card no. 6) :
This is also a double sided PCB (Size: 225mm X 275mm). This card houses the
logic circuitry to generate ‘IN COUNTS’, ‘OUT COUNTS’, ‘DUPLICATE IN
COUNTS’ and ‘DUPLICATE OUT COUNTS’ due to the dips caused from channel
inputs from the track detection points A, B, C and D. It also has combiner gates,
which combine the count pulses generated from all the detection points AB, CD, EF
17
18. and GH. The outputs of these gates are fed to the counter card (Card no. 7) for
counting and counts supervision. Card 6 also has an ‘INTERROGATOR’ circuit.
This generates four clock pulse trains. All these four pulse trains are staggered in
phase, with each of these pulse trains having a phase difference of 25 µ seconds as
compared to the subsequent one. The interrogator ensures that even if more than one
in count or more than one out count are fed simultaneously from different detection
point, the final count pulses fed to the counter card get staggered and thus counts are
not missed In addition to above, this PCB also houses the IN/OUT supervision
circuits, both counter checking each other. In case of any malfunction the system
latches to failure condition. This card also houses the 1st
out count inhibit circuit
which ensures latching up of the system in the event of 1st
count getting registered
being an ‘OUT COUNT’ instead of an ‘IN COUNT’.
(g)Counter Comparator (Card no.7) :
This is a double sided PCB (Size: 225mm X 275mm). This card houses two 10 stage
digital counters. One for counting the ‘IN COUNTS’ and the other for ‘OUT
COUNTS’. It also has count super- vision circuits, both for in counts as well as the
out counts, to check the integrity of the counters. In addition, there are two
comparators; one being a duplicate of the other, to compare the counts from the two
counters the ‘IN COUNTER’ and the ‘OUT COUNTER’.
(h)General Supervision Card (Card no. 8) :
This is a double sided PCB (Size: 225mm X 275mm). It houses the following
evaluator circuits:
i. Comparator Supervision.
ii. A series of monoshots forming a chain for static supervision i.e. to
prove the effectiveness of a number of DC levels of the system and
a few ground points.
(i) Relay Driver (Card no. 9) :
This is a double sided PCB (Size: 225mm X 275mm) and it houses the following
circuits:
(i) Level detector circuits for all the 8 channel inputs to ensure the presence
of proper channel input levels.
18
19. (ii) The ‘VOLTAGE MONITOR’, which serves as, a ‘WATCH DOG’ for
the +5V power supply to the Evaluator.
(iii) Relay driver outputs for driving the EV relay and the supervisory relay.
(j) Counts Display Card :
This is a double sided PCB (Size: 225mm X 275mm) containing four seven segment
LED’s for ‘IN COUNTS’ and four seven segment LED’s for ‘OUT COUNTS’ and it
can count up to 1023 counts in both the display. This card is mounted on front panel
of evaluator and counts are recorded in decimal system.
(k)EV & SUP Relay Indication LEDs :
The output of the Evaluator is used to drive two 12 Volts DC, 4F/4B shelf type relays
or 12 Volts DC, Q-style 4F/4B plug-in relays which are used to indicate the track
clear or track occupied indications to control signal aspects. Two 10 mm dia. LEDs
(Green and Red) have been provided in the front side of the Axle Counter Rack in a
metallic strip for locally displaying the position of the above relays. These LEDs have
to be suitably wired at the time of installation as per requirements from the terminal
strip connections provided at the rear side of the Axle Counter Rack.
(l) Mother Board :
This is a double sided PCB (Size: 420 mm X 260 mm) mounted at the back of the
Evaluator. The PCB is mounted at right angles to the other 10 PC Cards and serves
the purpose of providing various interconnections between them. The female parts of
the Euro Connectors are mounted on this PCB and corresponding male parts which
are mounted on the PCBs (Cards 1 to 10) mate with them when the card modules are
inserted in the unit. The mother board also provides access, through MS Couplers, to
feed various inputs like channel inputs from the tracks, power supply and trolley
protection and to feed outputs to the EV and the Supervisory Relays kept in the rack.
(m) Reset Relay :
This is mounted at the back of the Evaluator on the motherboard. A 67DP-24-4C3
OEN Relay is mounted on this PCB with a mounting socket. This Relay resets the
System whenever required to do so.
19
20. 2. ELECTRONIC JUNCTION BOX (EJB) :
The Electronic Junction Box houses PCB modules which are inter-connected through
motherboard. All the incoming / outgoing signals are terminated on the MS Couplers
(7 pin) mounted at the back of the junction box. Two types of outputs are available
from the EJB. The output of the EJB is sent to the Evaluator either through a 4 wire
or a 2-wire system.
(a) 4-Wire System:
In a 4-Wire System, two pairs of under ground cable are required to send transition
signal to evaluator for counting the dips. In this system there are three PCBs
consisting of common oscillator feeding to two transmitter coils in series and two
number of receiver amplifiers, one for each receiver coil. The sequence of cards is,
regulator and oscillator in first position, first amplifier in 2nd
position and second
amplifier in the 3rd
position from left to right.
Detail of individual cards:
CARD No. 1:
Regulator / Oscillator Card. (Size: 200 mm X 110 mm)
This is a single sided PCB (size: 200mm X 110 mm), which generates 5 KHz ±20 Hz
sinusoidal signal which is fed to the transmitter coils in series. The output voltage is
60 V ± 10% (rms) and current supplied is 420 mA ± 10% in the coils in series.
CARD No. 2:
Receiver Amplifier-1. (Size: 200 mm X 110 mm)
This is a single sided PCB of size same as that of card 1 and it rejects any noise over
riding in the signal by means of a two stage tuned amplifier. The output of the
receiver coil (1) is fed to the input of the amplifier. The output of the amplifier is
connected to the Evaluator and voltage is more than 1.2 V (rms).
CARD No. 3:
Receiver Amplifier-2. (Size: 200 mm X 110 mm)
This card is exactly similar to card no. 2 and is used for receiver coil (2).
20
21. (b) 2-Wire System :
In 2-wire system, a 4th
card is inserted in the EJB, which converts the frequency of the
second receiver amplifier signal to 3.5 KHz with the use of converters. Thus, 2-wire
system is having output on 2-wire and consists of 4 cards, namely the regulator /
oscillator card, the receiver amplifier card-1, the receiver amplifier card-2 and 4W /
2W card. This is used in block working at Advance starters only.
The sequence of cards is:
(i) Regulator / Oscillator Card.
(ii) Receiver Amplifier Card-1.
(iii) Receiver Amplifier Card-2.
(iv) 4W / 2W Converter Card
3. RESET BOX :
This box houses one 12 way PIRI terminal strip for terminating IN / OUT signals.
The indication LEDs of the reset box are fitted in LED holders and projected to the
front for indication. Green and Red indications are given for track clear and track
occupied conditions. The Yellow LED indicates co-operative permission for resetting
the Axle Counter.
4. TRACK DEVICE ASSEMBLY :
The Single Rail Track Device Assembly consists of two transmitter and two receiver
coils assembly, which are fitted with suitable mounting arrangements on the rail
camp, which in turn is fitted to the rails. The two transmitter coils at each of the
detection point are fed in series by a 5 KHz sinusoidal signal from the junction box,
which forms an electromagnetic field across the receiver coils. The receiver coil in
turn generates induced voltage. The induced voltage drops to a minimum whenever
there is an axle between the transmitter and the receiver coils.
(a) Track Device Transmitter :
The transmitter coil is placed in a FRP housing and it is potted in place by m-
seal compound. It is fixed on the rail clamp on the outer side of the rail. Each
transmitter coil will be provided with a 10 meter, 24 / 0.2 PVC cable.
21
22. (b) Track Device Receiver :
The receiver coil is housed in a composite aluminium fiber glass housing and is
potted in place by the means of an m-seal compound. The receiver housing is
fixed on the base clamp on the inner side of the rail. Each receiver coil will be
powered with a 10 meter, 24 / 0.2 PVC cable.
5. POWER SUPPLY :
The Power Supply, to the Evaluator is fed by a DC–DC Convertor. The various
output voltage of the DC–DC Convertor are as follows:
+ 5 V@ 5Amp. with ± 0.1% line & load regulation.
+ 5 V@ 5Amp. with ± 0.1% line & load regulation.
+ 10 V isolated @500 mA.
The DC-DC Convertor in turn derives its power from a + 24 V dc source i.e. a battery
bank.
The Junction Box (JB - 531) and the Reset Box (RB – 257B) are also powered from +
24 V dc battery bank.
All the supplies have over current protection while 5V supply has additional crow bar
protection at 6.2 volts.
PRODUCTION TESTING & TEST PROCEDURE:
The semi – conductor devices like diodes and transistors used are of high reliability type.
The other vital components like ICs mostly are the commercial grade ICs which will
undergo burn in at 60°C with dc power ‘ON’ for 72 hours.
This will eliminate the failure of critical components after the assembly of the PCB.
WAVE SOLDERING:
All the PCB’s assembly will be wave soldered for good reliability and also coated with
lacquer to withstand climatic conditions.
22
23. INSPECTION:
Each unit will be examined for proper workmanship, fitness, finish and proper markings.
Also each unit will be tested thoroughly as per the test schedules mentioned in the test
report before the final shipment.
SPECIAL FEATURES
The Universal Axle Counter has the following special features:
PCB LAYOUT:
Better PCB layouts to have supply feeding and decoupling for better noise immunity.
MOTHER BOARD:
The use of mother board gives extra noise immunity as compared to back panel wiring.
RACK:
The Evaluator is housed in a rack fabricated out of M.S. sheet. This gives good noise
immunity against electromagnetic interference.
SHIELDING:
The Rack is well shielded for better noise immunity. All the metallic frames of the rack
are interconnected to the main frame by means of 34 / 0.3 wire. Shielded cables will be
used in system, shield of which is connected to the back panel of the Evaluator.
CARD INSERTION:
Each Card along with a module is guided separately.
CARD MODULES:
Each Card is provided with a module along with the identification label.
CARD POLARISATION:
Polarizing holes on the card modules and guiding pins from the Mother Board side are
used to provide card polarization to ensure correct card slotting.
23
24. MODULE TIGHTENING SCREWS AND CARD HANDLES:
Module tightening screws are provided to fix the cards along with the module in the unit
smoothly. By loosening, the cards can be removed from the unit. Two card handles are
provided on each module. The modules can be taken out with the help of these handles.
COUNTS DISPLAY:
The Counts display is given on a PCB and mounted on the front panel inside and is
viewed through display viewing plate at the front panel of the Evaluator.
EVALUATOR MARKINGS:
In each unit input /output labels, the supply, channel markings and trolley protection A /
B, C / D are marked.
CHAPTER 4
4. OTHER PRODUCTS OF CEL
4.1. SPV PRODUCTS:
SOLAR WATER PUMPING SYSTEMS:
A Solar Photovoltaic Water Pumping System essentially consists of an SPV panel or
array directly powering a water pump. Water pumped during the day can be stored in the
storage tanks for use during the night.
CEL offers SPV Water Pumping Systems for both shallow as well as deep well
conditions. Such systems have been deployed all over the country. The system has also
been exported to many developing countries.
The generated electricity from the SPV array is fed to the pump through a switch.
Normally low storage batteries are provided, as the water can be stored in the storage
tanks if required.
SOLAR PHOTOVOLTAIC LIGHTING SYSTEMS:
CEL’s Solar Photovoltaic Lighting Systems are ideal sources for providing
indoor/outdoor illumination in remote and unelectrified settlements/ villages. The SPV
Lighting System essentially consists of an SPV panel battery, a charge controller and
24
25. lights. The SPV panel converts the sunlight incident on it directly to DC electricity that
can be stored in the battery and used to energize the lights when required. The charge
controller prevents the overcharging and deep discharge of the battery.
SPV INDOOR LIGHTING SYSTEMS:
Two types of indoor lighting systems are available (DLS-02 and DLS-04) depending on
the lighting requirements. DLS-02 has two numbers of 9W luminous efficiency lamps
with wall mounting fittings. DLS-04 has four such lamps. Each lamp can give the output
of 60-watt incandescent lamp.
SPV OUTDOORS LIGHTING SYSTEMS:
These systems use a weather proof 18-watt or 20-watt fluorescent tube light fittings. Two
models SLS-03 and SLS-06 are available depending on hours of operation in day.
Switching ON at dusk and OFF after specified hours of operation is automatic. The SPV
panel, battery and the tube-light fittings are mounted on a 4M long pole.
SOLAR LANTERNS:
CEL Solar Lantern is a versatile and a reliable source of lighting. It consists of a lantern,
a SPV module and a connecting cable. The SPV module when exposed to light charges
the battery in the lantern. This stored energy in the battery is used to operate the lamp
when required.
SPV MODULE:
A number of high-grade crystalline silicon solar cells, interconnected in series
combination and hermetically sealed with a toughened glass cover, form a SPV module.
SALIENT FEATURES:
ENVIRONMENTAL FRIENDLY
PORTABLE
RUGGED AND DEPENDABLE
25
26. APPLICATIONS:
EMERGENCY LIGHTING SOURCE
LIGHTING SOURCE IN REMOTE VILLAGES
LIGHTING AT PICNIC SPOTS AND FARM HOUSES
GARDEN LIGHTING
LIGHTING AT MILITARY OUTPOSTS
4.2. MILESTONES OF SPV SYSTEMS DEVELOPMENT AT CEL
SPV operated Radio set in Jammu & Kashmir - 1978
SPV Irrigation Water Pumping System installed at Kalyani, West Bengal – 1979
SPV Pumping System for drinking water near Jaipur – 1980
SPV Community Lighting Systems installed at SOS children’s village, Leh,
Ladakh, J&K – 1980
SPV Community Television Systems installed at Kalyani, West Bengal – 1980
Special SPV Power Pack for the first Indian scientific expedition to Antarctica
– 1981
First SPV Power System for unmanned off-shore oil well platform of ONGC –
1982
SPV operated Diesel Dispensing Pump – 1982
Export of SPV Water Pumping and other System – 1983
First SPV powered stand-alone Street Lighting System in Salojipali, Andhra
Pradesh – 1983
SPV foldable modules for Everest-84 Expedition – 1984
SPV systems for Direct Reception community TV sets of Doordarshan – 1985
SPV Systems for Cathodic Protection of oil pipelines – 1985
SPV systems for Vaccine Refrigeration in village Health Centers –1985
26
27. Design and supply of first SPV Systems for very low powered unmanned TV
transmitter (VLPT) & TV Receiver Only (from INSAT) (TVRO) terminals of
Doordarshan - 1986
Supply of SPV Power System for weather monitoring, lighting and entertainment
at an Avalanche Study Station at Rohtang Pass (ALT : 3600 meters/12000 ft.) in
the Himalayas – 1986
SPV powered Lighting and Television System for army at Siachin (ALT : 3600 –
5500 meters / 12000 ft.) in the Himalayas – 1987
Supply of first 2 KW power SPV Village Power Pack – 1987
SPV systems for warning signals at Unmanned Railway Level Crossings – 1988
SPV Rural Deep well Water Pumping Systems for National Drinking Water
Mission – 1989
SPV Power System for Rural Telecommunication transmission and switching
equipments – 1989
Supply and installation of SPV Systems in village Hitam-ulu, Sumatra,
Indonesia – 1990
SPV Lighting Systems for Adult Education under National Literacy Mission –
1990
Supply and installation of 6 KW Power Plant at Kariawali village in U.P. – 1990
Supply and installation of Asia’s first 100 KW SPV Power Plant at Kalyanpur
village near Aligarh, U.P. – 1992
10 KW Power Generator for M.S. Swaminathan Foundation at Taramani,
Madras – 1993
Supply of Foldable Lightweight SPV modules for powering Man pack
Communication – 1993
Equipments for the defense services to operate in the temperature range from –
30°C to +55°C.
4.3. CATHODIC PROTECTION SYSTEM
27
28. INTRODUCTION:
M/s Indian Oil Corporation Limited is presently laying 18” dia., 437 Km. long pipe line
in 2 segments for augmenting the capacity of existing OD 498 Km. long Haldia-Barauni
Crude Oil pipeline from Haldia to Barauni.
Owner intends to provide permanent cathodic protection system consisting of 13 nos. of
impressed current cathodic protection station to cathodically protect the underground
coated pipeline for a design life of 35 years.
BASIS IN BRIEF:
Permanent CP System has been designed for CTE coating having coating resistance of
7000 ohm / m factor of safety as 1.3. Designed life of anode bed is 35 years and that of
the CP system is 20 years.
SUMMARY OF PERMANENT CP SYSTEMS:
Designed current density considered for design 125 microA/sq. metes.
Total no. of CP stations 13 Nos.
Total designed current for entire span 103.8 A
Max. Design current of CP station 10 A
Total no. of 22 Kg high silicone chrome anode 250
PROJECT INFORMATION:
The Haldia – Barauni Augmentation pipeline is starting from Haldia and it terminates
approximately 473 Km. away at HBPCL near Barauni.
Coating Details:
The pipelines shall have yard coated coal for tar coating with fiberglass reinforcement.
The coating resistance in normal soil shall be 7000 Ω/m.
Depth of pipeline:
Generally the HBPCL has proposed the pipeline to be laid at minimum depth of 1 meter
from the ground level. Depth may increase to 9 meters. or more depending on the soil.
28
29. High silicon-chrome anode and anode beds:
The anodes shall be High Silicon Chromium cast iron, cylindrical type. Anodes shall be
provided with encapsulated heads and heat sink caps connected at top.
The technical data of the Hi-Si-Cr-Fe anodes assembly shall be as under.
ANODE TYPE : Hi-Si-Cr-Fe Anode
DIMENSIONS : 65 mm. Dia. & 1 meter long
WEIGHT : 22 Kg.
4.3. FERRITES PRODUCTS:
INTRODUCTION TO FERRITES:
Ferrites are dense homogeneous ceramic structures having a general molecular formula
MFe2O4 where M is an oxide of a divalent metal. When M has more than one metal than
it is called Mixed Ferrite.
Ferrite has a process flexibility, which permits easy and economic moulding into much
different geometry. Besides there, Ferrites are advantageous because they have high
electrical resistivity resulting in some eddy current loses over a wide frequency range,
high permeability and time and temperature stability as compared to other metallic
magnetic materials such as silicon steels.
The ferrites are used in Transformers, Telecommunications, TV industry, Antennas,
Defense Equipments, etc.
Application of different types of Ferrite cores:
The ferrite cores that are produced in CEL are available in different sizes and their uses
are as follows:
a) Pot cores & RM cores:
These are used in stable low loss Filters, Inductors requiring high Q, Chokes,
Proximity switches, R.F. Transformers, low power Converters & Inverters etc. for
Telecommunications, Axle Counter System for Railways and other Professional
electronic applications.
29
30. b) Toroids :
They are used in Pulse Transformers, Delay lines, Chokes, Converter / Inverter
Transformers, Wide Band Transformers, Impedance matching Transformers, etc.
c) Blocks:
They are used for Transmitter and Receiver application of Axle Counters. They
can also be used as building blocks for making high power transmitters.
d) E, EI, ETD & EC Cores :
These types of cores are used in the Inverter/Converter Filters, Chokes, Inverters
for Fluorescent Lamps and Flash Light Inverters, Switch Mode Power Supply for
Television and Computers, etc.
e) U & UI Cores :
These cores are used in Insulation Testers, DC-to-DC Converters, DC halogen
lamp Inverters, Ultrasonic Cleaners and high voltage Inverters. By stacking of
these cores, high power transformers in Kilowatt range can be manufactured.
FERRITE PROCESS FLOW CHART
30
Iron Oxide
Zinc Oxide
Manganese
Oxide
Batch
Mixing
CALCINATION
(PREFIRING)
MILLING
GRANULATION
(SPRAY DRYING)
BINDERLUBRICANT
PRESSING
SINTERING LAPPING PRODUCTION
TESTING
AIR GAP
ADJUSTMENT
PRINTING
STORES
AND
DESPATCH
31. Fig.4.1.Ferrite process flow chart
CHAPTER 5
5. NEW PRODUCTS:
5.1. SINGLE SECTION DIGITAL AXLE COUNTER
A state-of-the-art Digital Axle Counter has been developed by CEL for track monitoring
of single section in railways.
The system is designed with :
• High frequency track coils.
• Track side electronic counting unit including vital relay drive.
The system has two detection points for monitoring either end of the section. When the
train is entering the section the wheel counts are registered and stored in the 1st
SSDAC
unit. When the train is entering the section the wheel counts are registered and stored in
the 2nd
SSDAC unit. After exchange of counts stored in both SSDAC1 and SSDAC2
units, the section is declared as ‘CLEAR’ in case the counts are equal. Otherwise the
section is shown as ‘OCCUPIED’.
The health of SSDAC1 and SSDAC2 units are continuously monitored and proved in
vital relay drive circuits.
The vital relay drive is available independently at either end of the section from SSDAC1
and SSDAC2 units.
5.2. SOLID STATE INTERLOCKING
Solid State Interlocking (SSI) is Signaling System to select and operate the routes in
station for guiding the movement of the trains. The system replaces the conventional
Route Relay Interlocking. The system is designed with “2 out of 2” Microprocessor with
hot standby. The system has software redundancy.
The operator panel is used to control and command and display the status of SSI.
31
QUALITY
ASSURANCE
32. FEATURES:
• System capacity: 450 Input, 72 Output.
• Dual Microprocessor Based (2 out of 2) Fail-safe design.
• Hot standby for High System Availability.
• On Line self-diagnostic facility.
• Data Logging with Time Stamping of all SSI Inputs and Outputs for Off-line analysis.
• Onto Isolated Inputs and Outputs.
• Modular design for easy maintenance and expansion.
5.3. SOLAR POWERED RAILWAY LEVEL CROSSING RADIO
WARNING SYSTEM:
(SOLARGUARD ™)
CEL has developed this system, in association with Research, Designs and Standards
Organization (RDSO) for providing early warning of a train / locomotive approaching
unmanned level crossing, to the people and road traffic crossing the Railway line.
SYSTEM OPERATION:
A track device actuated solar powered VHF transmitter located 3-4 Kms, from the level
crossing (i.e. Far End) sends a coded radio signal towards the level crossing when an
approaching train crosses the Far End. The radio signal is received by solar powered
receiver located at the level crossing (Gate End) which after decoding the signal actuates
an Audio- Visual Alarm for forewarning the traffic. The system is ideal for remote
railway level crossings. The ruggedized system is under extensive field trials.
32
33. CHAPTER 6
EPILOGUE
These 30 days Industrial Training has led me to understand the various designing,
assembling and the manufacturing processes of equipments in the industry, CEL
Sahibabad.
It has also enhanced my knowledge about the functioning and management of an
industry, which I am sure, will be beneficial to me in my career. On the very first day of
my training which was started on 30th
June 2016 our mentor told us about the basic
structure of the organization, how it works, what they manufacture and in country what
they are contributing. I feel very good to know that Central Electronics Limited is nations
pioneer for manufacturing Solar Photovoltaic Cell. They are contributing a lot in the field
of green and clean energy because they also manufacture Solar Cells and plates. As per
my background is from Mechanical Engineering so I get opportunity to start my training
in the department who manufactures Universal Axle Counter. Basically Universal Axle
Counter is used in the railways coaches for signaling purpose. It plays very important role
in Indian Railways to run the train. It was a very good experience for me at CEL, I learn a
lot. During my training I also visited their other part which is dedicated to DRDO and
manufactures components used in rocket and missiles in their emission system. I also
gone through their Automated Solar Cell plant in which only CNC and other robotics do
the work by own
SURJEET PANDEY
B.tech Final Year
33
