a report on emt & solar panel production REIL

EMT & Solar Panel Production

CHAPTER 1 COMPANY PROFILE 1.1 INTRODUCTION REIL is Rajasthan Electronics & Instruments Ltd. It is a public sector unit and it has a prominent place amongst the electronics industry of Rajasthan. It was established in 1981. It is situated at the Kanakpura industrial area about 12 Kms from Jaipur city. REIL has a joint venture between the Government of India & the Government of Rajasthan, through their respective institutions. Government of India & Government of Rajasthan holds 51% & 49 % share in this company respectively. REIL has completed twenty-five years in service of the nation, especially the rural India, rendering services and products in the technology areas of electronics, renewable energy, information technology and industrial electronics. The products address needs of the dairy sector, rural lighting energy, energy metering and egovernance.

Fig 1.1 View of REIL

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EMT & Solar Panel Production REIL subscribes to the belief that the path to social and economic progress of the country lies through the villages and is committed to the up liftment of the rural economy by taking technology to the villages. REIL is an ISO9001 public sector undertaking started as a joint venture between RIICO (Rajasthan State Industrial Development & Investment Corporation) and Instrumentation Limited, Kota. During my training period I have taken my training in four department of this organization. These are - Agro dairy division, Renewable energy division, Industrial electronics division and Quality a REIL aims at retaining its primacy in the area of Rural Electronics, Non-conventional Energy Systems and Information Technology by developing, manufacturing and marketing quality products and by offering quality services. The company was conferred the status of a "MINI RATNA" by the Department of Public Enterprises, Ministry of Industry, Government of India in 1997 on account of it's good all round performance and excellent products. The company has added another feather in it is cap by establishing a Quality Management system for its operations and has been certified as an ISO 9001 firm w.e.f. 31st July, 1998. The area of business extends to manufacturing and marketing of electronic products are Agro-Dairy division, Renewable energy division or Industrial Electronics division Information Technology. Recognition of REIL‟s achievements in the field of rural electronics has come in a variety of ways- in customer satisfaction, in its prestigious establishment of the Rural Electronics Technology Center in 1990 and in an award of the Department of Electronics for excellence in Electronic- now named as department of Information Technology under Ministry of communication and Information Technology, for the year 1991 and 2001.[1] REIL‟s remarkable performance in India and abroad has encouraged the company to its sights on international markets with are newed thrust. In more than two decades of its existence REIL has played a vital assurance department. The Company, through its market driven in-house Research & Development(R&D), (recognized by the Ministry of Science and Technology, Government of India), has developed and introduced a number of new products such as data processor Electronic Milk Tester (DPEMT), Electronic Milk Weighed System, Automatic Milk Collection Station, Data Processor Milk Collection Unit (DP-MCU),Raw Milk Reception Dock (RMRD) Automation System, PC based Society Accounting & Management System, Animal Database Management System, Smart Automatic Milk Collection Station (SAMCS), Auto Zero EMT, Solar EMT in the diary sector.

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EMT & Solar Panel Production REIL is also in the business of Renewable Energy through Solar PhotoVoltaic (SPV) Technology where It started its operations, in 1986, with manufacture of SPV Modules and Systems. Since then it has supplied and installed numerous SPV Stand alone Street Lighting System, SPV de-centralized Domestic Lighting Systems, SPV Water drinking Systems, SPV Dusk Dawn Switching Systems, SPV Lanterns, SPV powered Railway Signaling Systems, Microwave Repeater Stations, Satellite Ground Terminals and Grid Interactive Power Plants etc. In this area Company has produced SPV Modules of about 8 MW generating capacity. REIL entered the business segment of voter identity card, in 1994, with state-of-art technology i.e. digital imaging and data processing technology, for large scale production of EPIC cards. It also produced over 60 Lac cards for the state of Gujarat. It is also into development and manufacture of Electronic Energy Meters, for domestic user connection, with diversified range of futuristic products like keypad based pre-paid energy meters and smart card based pre-paid meters. It already supplied about 100000 Electronic Energy Meters to State Electricity Boards. The company has a strong in-house Govt. recognized Research & Development Division which has enabled the company to effect considerable improvements in the initial adopted technologies. Indigenisation of the Milk Testing equipment and incorporating the latest State-of-the-Art microprocessor designs over the initial and older LSI designs has enabled more features and new add-on equipment has been developed to provide integrated system solutions. A prestigious collaboration with the Department of Electronics (DoE) in 1990 for the establishment of Rural Electronics Technology Centre and an award from DoE for Excellence in Electronics in 1991, testify REIL's achievements in the field of Rural Electronics. The Consistency in Excellence is recognized with repeated award for Excellence in Electronics for the year 2001, given by the Ministry of Communication and information theory. Rajasthan Electronics & Instruments Limited (REIL), as a commercial organization, has been in operation for the past 27 years with a proven track record of profitable performance, professional management and service to the rural masses through electronic products for the dairy/milk cooperatives and renewable energy sectors. REIL commenced its foray in the Dairy sector with the manufacture of Electronic Milk Testers under the technology license from National Dairy Development Board (NDDB), by using the AIET/ECE/PTS/3

EMT & Solar Panel Production technology developed overseas by Foss, Denmark. The Company entered the area of Renewable Energy through Solar PhotoVoltaic (SPV) technology, in the year 1985. The Company started its operations with manufacture of SPV Modules and control electronics for SPV powered village Street Lights.

1.2 PRODUCT IN WHICH REIL IS INVOLVED (a) Electronic Milk Tester (b) Automatic Milk Collection Station (AMCS) (c) Data Processor- Electronic Milk Tester (d) Electronic SNF Tester (e) Solar Photo Voltaic Modules (SPV) (f) Radio Frequency Identification (RFID) (g) Spot Billing Machine During my training I have gone through the four department of REIL these are Renewable energy division, agro dairy division, industrial electronics division and quality assurance department. I also visited the Research & Development department of REIL

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CHAPTER 2 AGRO DAIRY DIVISION 2.1 INTRODUCTION The electronics division kicked off its operations in 1982, the year of formation of the company and has notched up many credits in the last one and a half-decade. The operations started with the electronics milk tester, under technical collaboration with FOSS electric of Denmark and assembly of electronic milk tester (EMT), from kits supplied by the collaborator initially. The company has rapidly absorbed and assimilated the technology, successfully indigenized the product and in response to customer requirement (based on micro-controller technology) to suit the needs of the products into a more versatile system, developed in-house through its own development efforts, called the Milk Collection Station.

2.2 ELECTRONIC MILK TESTER During my training period the first division was agro dairy division and the main product of agro division is electronic milk tester, It measures the fat content instanteously on a digital read out. it does not involve the use of corrosive chemicals. It works on light scattering principle.

Fig 2.2(a) Electronic milk fat tester

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EMT & Solar Panel Production It operates on AC-main as well as on battery within built battery charger & automatic switch over to battery in case of power failure .Basic objective in the dairy development program is to increase the production of milk. Milk collection depends on prompt payment of fair and correct price to encourage producers to increase milk production. The system of payment based on quality (i.e. fat content ) discourages adulteration and encourages producers to increase production of high quality milk. it is further necessary that each sample of milk should be tested of its quality and testing should be completed within 2 to 3 hours time, in order to make correct payment. Milk sample would also get spoiled if not tested immediately in the absence of facilities to preserve them, especially at village level. Old traditional „GERBER‟ method of testing milk by chemicals has many inherent drawbacks, such as human error, multistep method, handling of corrosive chemicals and different type of glassware. All these add to the cost and time to milk testing. A quicker reliable and economical method of milk fat testing has therefore become inevitable and an immediate problem to solve. In the light of some problems faced by “GERBER” method of testing, it was felt prudent, to involve a system which should solve these problems. The process of fat measuring by EMT has involved basic principle, diluents preparation, homonization, auto zero setting etc.

Fig 2.2(b) EMT assembly room

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2.3 FEATURES OF EMT  Auto zero facility  Performs 110-130 samples per hour  Instant measurement and display of milk fat  Instant calculation of amount payable  Facility to feed milk weight directly through keypad in absence of weighing machine  Operation with 4*4matrix hexadecimal keypad  Printing facility  Instant transmission of data‟s on remote display  7 segment LED  Suitable for interface with electronic weighing machine through serial port  Data storage up to 800 members for 30 days  Data transmission speed 2400 baud  Data storage on EEPROM  Built in battery charger  Runs on mains and battery both 

Slip printout by 80 columns serial dot matrix printer.

Fig 2.3 Features of EMT

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2.4 TECHNICAL SPECIFICATION OF EMT Performance Data Installation Measuring range

0-13% fat

Requirements Power Supply

AC: 220-24OV (Max + 10%, Min 15%) DC: 12V, 6A (Max 16 V; Min 10.5V) A fully-charged 120 AH battery will last for at least 10 hours of operation.

Capacity

120-150 samples/hour

Accuracy (Sd)

0.06% for 0-5% fat

Ambient temperature

5-45 0C

Dimensions (HxWxD)

23x31x53 cm

Space requirement

60x80 cm

Weight (without diluent)

16 kg.

0.10% for 5-8% fat 0.20% for 8-13% fat Repeatability (Sd)

0.03% for 0-5% fat 0.04% for 5-8% fat 0.08% for 8-13% fat

Sample volume Diluent volume

0.5 ml/test

6.5 ml/test

Table 2.4 Technical specifications of EMT

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2.5 BASIC PRINCIPLE OF EMT Electron milk tester is based on the photometric measurement of light scattered by the milk sample. The light is scattered by the fat globules, acting as small prisms. Not only fat globules to the light scattering but also the proteins may affect the measurement. To eliminate their influence, it is necessary to dissolve them. EDTA solution is used for this purpose. 

All the fat globules do not have the same size. The measuring system requires a Constant globule size to provide a mixed relation between the amount of light scattered to the fat content. The range of globule size is limited in the milk tester to a very narrow region outside the natural range. This is achieved by homogenizing and bringing the globule size into the range of 0.5 to 1.5 microns.



Light rays from a photo lamp pass through the layer of fluid in the cuvette and are scattered according to the sample of fat globules in the sample. More is the amount of fat present in the cuvette, more is the light scattered and less light scattered and less light passes through the cuvette. The rays that do pass through the cuvette strike photocell, producing a current proportional to the light intensity. The current is fed to a digital read out unit which gives direct fat percentage read out.

Fig.2.5 Front view of EMT

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EMT & Solar Panel Production Different assemblies of EMT are as follows-

2.5.1 Photometer The photometer consists of a lamp, lamp housing and detector assembly. The detector assembly includes the cuvette and photocell.

Fig 2.5.1 Assembly of photometer

2.5.2 Cuvette It is made of two hundred glass discs. One has a ground depression of 0.4 mm the other has two small holes to provide inlet and outlet to the cuvette.

2.5.3 Photocell It is a selenium barriers / silicon detector photocell. Care should be taken not to expose this photocell to light when not in operation.

Fig 2.5.3 Photocell AIET/ECE/PTS/10


2.5.4 Temperature testing (thermo block) Temperature of the thermo block is set with the help of power PCB. Maximum temperature is 50.1 to 50.2 degree Celsius and minimum temperature is 49.1 degree Celsius. All measurement are done with the help of electronic thermo meter.

Fig 2.5.4 Thermo block

2.6 PREPARATION OF DILUENT (a) Diluent is used to dilute the milk sample and dissolve the proteins. (b) Chemicals required to prepare 10 liters of diluent are as follows: 

EDTA sachet - 52.6 gm containing EDTA powder 45.0gms ,disodium Hydroxide 7.6gm Diluent



Triton-x-100 -- 0.5ml (10 drops) ( Emulsifier )

 Antifoam -- 0.5ml (10 drops)

2.6.1 Procedure  Take a clean 10 liter plastic container and add one liter clean water. Add contents of EDTA sachet, containing diluents' powder for 10 liter solution add 0.5 ml of triton-X-100 and 0.5 ml antifoam. Put the lid on the container and shake it until all the chemical are dissolved, then add liter clean water to prepare 10lt of solution and shake again to mix the solution.  The PH of this solution should be between 9.5 to 10.1 diluents before the antifoam becomes inactive. Diluents can be kept longer if antifoam is added to the solution from time to time (0.5ml for every 2 weeks). warm up before starting measurement. This is done by switch on the EMT half an hour to one hour before measure.

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2.7 SUB ASSEMBLIES

Fig 2.7 EMT Tree

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2.7.1 Cable assembly In this all cables are assembled for different purposes use in EMT.

2.7.2 Charging regulator It has two functions When battery has been discharged it limits charging current to 5 amps, and other is When battery has been fully charged and reaches 14.1D charging regulator turns off charging current entirely.

2.7.3 Control panel Output of power is given to measure PCB where current from photocell is led to 3 position switch to IC where current is converted to voltage.

2.7.4 Power supply (power PCB) This is a serial regulator with no current limit. Base current goes to ground via resistor.

2.7.5 Thermo block It is used for temperature control. it consists of Heater resistance, thermo fuse NTC, steel coil. An NTC resistor sensor is located in a hole at rear of thermo block. Temperature control of power supply PCB contains a bridge circuit which is adjusted to balance when NTC is 50degreeC.

2.7.6 Dispenser unit It consists of EDTA powder (dissolves proteins except fat) + distilled water + titrounax (lubricant) +antifoam (reduce foam).

2.7.7 Homogenizr Unit It uniforms fat globules solution enters and a film is made of sample. If the fat is of high amount film is thick so light is more saturated thus voltage decreases. If fat is less film is thin, voltage increase

Fig 2.7.7 Homogenizr unit

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2.8 TECHNICAL FAULTS IN EMT 2.8.1 Rear panel checking All components of the rear panel are checked using a millimeter. It is a part of final quality control. Continuities of the circuit are checked.

Fig 2.8.1 Rear panel of EMT

2.8.2 PCB calibration 2.8.2.1 Measure PCB PCBs are programmed as per need and requirements and fat content. REPEAT and ZERO buttons are checked for functionality. 2.8.2.2 Power Supply PCB It has two operations, Temperature control and Voltage level supply(Low 5.9 V to 9.9V) both are tested. 2.8.2.3 Charger PCB It is checked for charging at 14.1 V for a 5 ampere battery.

2.8.3 Valve testing There are three types of valve which are classified on the basis of the pressure at which they work. These are 

Red valve takes diluents to dispenser unit from inlet.



Green valve dispenser to dispenser again.



Blue valve outlet of checked sample (waste).

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2.8.4 PCB cleaning PCBs are cleaned with the chemicals meant for the same. All the dust gets removed and PCB is ready for installation after this.

Fig 2.8.4 Calibration of EMT

2.8.5 Mechanical testing Mechanical connections and joints are checked. Attachments are tightened to provide strength to the machine.

2.8.6 Life test It is done to check mechanical faults and leakage after overall testing to see how the device is working in practical situations.

Fig 2.8.6 Life Test Machine

2.8.7 Dispenser test Leakage of the milk and diluents chambers is checked. If found, dispensers are sent back for repairing. AIET/ECE/PTS/15


2.9 INSTALLATION OF EMT  Place of installation should be such that there should be sufficient space for diluents container and battery also.  Check 1amp fuse in the main fuse holder and 10 ampere fuse in the battery  Connect power cable on mains. Use only 12v motor car batter. Connect red lead of battery cable to „+‟ pole of battery and black lead to „-„ pole. Connect other end of electronic milk tester.  Set selector switch at line/battery & mains switch at ON. Power will now be supplied to EMT from battery. As long as main switch is at ON position, current from mains will keep the battery charged. If the power fails, battery will still be able to supply enough current several hours of operation.  Prepare the diluent in the container.  Connect one end of the plastic thick pipe to the INLET stub at the back of EMT and attach the filter unit to the other end which is then placed in the diluents container.  Connect one end of the plastic thin pipe to the OUTLET stub and place the other end in the waste container.  Place empty beaker under milk intake tube and push „milk in‟ and „MILK OUT‟ buttons alternatively until no bubbles are seen in syringes. End by pushing „MILK OUT‟ button.

Fig 2.9 Installation of EMT AIET/ECE/PTS/16


2.10 PROCESS OF MEASUREMENT (a) Set power switch at ON (b) Set battery switch at LINE/BATTERY. (c) Fill bottle with diluents (d) Empty bucket for waste. (e) Do not start procedure three until EMT has been switched ON at least half an hour. (f) Setting display at 0.00. (g) Place milk beaker under milk intake. (h) Push milk in, milk out. (i) Move mix beaker to mix intake. (j) Raise and lower handle 6 times. (k) Push repeat button so display blinks. (l) Push zero buttons so display reads 0.00. (m) Push repeat so display doesn‟t blink (one decimal).

PROCESS FLOW CHART COMPONENTS

FINISHED INST. ( EMT )

RICEIPT STORE

CLEANING AND PACKING

COMPONENT SOTORE

SUB ASSEMBLY

BASIC UNIT ASSEMBLY

SUB ASSEMBLY STORE

INWARD GOODS INSPECTION

ASSEMBLY CHECKS

SUB ASSYQUALITY CONTROL

CALIBRATION

BURN IN TEST

ELECTRICAL CHECKS

MECHANICAL CHECKS

Fig 2.10 Process Flow Chart

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EMT & Solar Panel Production After drying and zero setting measurement can begin. First result after zero check /zero setting should not be recorded as it will be little low. Therefore measure the first sample after zero check twice and record only second result. Turn the milk sample gently upside down a few times. Place the sample under milk intake and fully press³MILK IN´ button. Slowly remove the sample without touching the milk intake tube. Place clean milk under milk intake so that it fills into notch on the side of EMT Press „MIXOUT‟ button in all way and diluent into mix beaker. Move mix beaker to mix intake tube and position it so that it rest in notch operator homogenizer handle up and down 3 times in a steady measurement when the handle is pressed down and the third time let it test in bottom position and result will soon appear on the display empty the mix beaker completely and in ready for the next sample.

2.10.1 End of Measurement Place a clean, empty mix beaker under milk intake tube and press „MILK IN‟ and „MIXOUT‟ buttons twice alternately to fill mix beaker with diluent. Place the mix beaker under mix take and operate the handle up and down six times to flush the cuvette. Switch off the EMT.

2.10.2 De-airing the homogenize Air will enter the homogenizer if the handle is raised when there is no liquid present at the mix intake tube. Place the mix beaker under milk intake tube and press „MILK IN‟ & „MILK OUT‟ buttons twice to fill the beaker with diluents. Now place the filled mix beaker under the MIX INTAKE tube and raise the handle. Loosen the bleeder screw on the top of mix intake valve. Let the handle drop by its own weight and tighten the bleeder screw again. Operate the handle three more times up and down to be sure that all air is out of the system

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CHAPTER 3 VARIANT OF ELECTRONIC MILK TESTER 3.1 OPTICAL MILK ANALYZER The optical milk analyzer work on the principle of photometric measurement of light allowed passing through the measurement device in accordance with the milk density. The milk density is measured accurately and result is displayed quickly on a display after temperature correction to the actual sample temperature for the convenient read out by the user and the milk producer. The instrument allows capturing of milk FAT from an electronic milk tester and displays FAT and SNF% on optical milk analyzer LCD. Option for display of CLR is also available. The instrument is simple, economical, reliable and rugged for milk analysis. The instrument can be integrated with automatic milk collection unit for quick measurement of milk parameter, processing and storing them for record. The instrument is ideally suited for the village milk collection centers, milk chilling centers etc.

3.1.1 Features 

Display % solid-non-fat (SNF).

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Result is independent of sample temperature.



Simple and inexpensive method of milk analysis.



Effect of air bubbles on accuracy eliminated.



Performs 150 tests per hours.



Quick measurement and instant digital read out on LCD.



Low power consumption.

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3.2 DATA PROCESSOR ELECTRONIC MILK TESTER (DPEMT) Data processor electronic milk tester (DPEMT) comprise of four main units, electronic milk tester, milk weighing system & remote display. EMT measures the fat content of the milk. The membership codes of individual member are entered manually by keyboard. The weight can be entered either manually or captured automatically. The equipment gives the print out of the transaction of milk brought in by each producer. Data processor electronic milk tester work on the principle of photometric measurement of light scattered by the fat globules present in the milk sample. The measuring procedure follows the conventional system of dilution , mixing and photometric measurement.

Fig 3.2 Data Processor EMT

3.2.1 Technical Specifications Measuring Range

0-13% fat

Capacity

110-130 Samples per hour

Sample Volume

0.5 ml/test

Diluent Volume

6.5 ml/test Table 3.2.1 Technical Specifications

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3.2.2 Features  Performs 110-130 sample per hour. Instant measurement and display of milk fat.  Instant calculation of amount payable.  Facility to feed milk weight directly through keypad in the absence of weighing machine.  7 segment display.  Printing facility.  Instant transmission of data remote display.  Runs on mains and battery both.  Built in battery charger. Data storage up to 800 members for days.

3.3 AUTOMATIC ELECTRONIC MILK TESTER Automatic Electronic Milk Tester (Auto EMT) manufactured by REIL is simple, economical and accurate milk fat testing instrument. Manual operation has been automated by using high torque AC synchronous motor to make more reliable, rugged and to ensure proper homogenization for higher fat sample. Percentage of fat content is displayed quickly and accurately on a digital read out.

3.3.1 Working Principle Automatic Electronic Milk Tester works on the photometric measurement of light scattered by the fat globules present in the milk sample. The measuring procedure follows the automated system of dilution, mixing, homogenization and photometric

Fig 3.3 Automatic Milk Tester AIET/ECE/PTS/21


3.3.2 Technical Specifications Measuring Range

0-13% fat

Capacity

150-180 Samples per hour

Sample Volume

0.5 ml/test

Diluent Volume

6.5 ml/test

Table 3.3.2 Technical specification of Auto EMT

3.3.3 Features  Auto intake of milk sample  Auto homogenization  Auto zeroing  Process indication  Quick and instant read-out  Runs on mains  Measures up to 13% fat  Requires small quantity of milk  Performs 150Min.-180Max. test per hour  Inexpensive method of testing.

3.4 MILKO SCAN MINOR The milko scan minor is an alternative because of its lower cost and less time used per sample. It is easy to use and has a finite performance. The results are presented to you in approximately 90 seconds and enable you to standardize milk or perform milk payment analysis on fat and other parameters. With milko scan minor you get a simple analysis of whole range of parameters. It is possible to prepare a sample set on the pc before collecting results and prepare a manual sample. This makes it easy for non skilled users to operate the instruments. Analysis of milk and cream can take place instantly. There is no need for special sample treatment and no use of hazardous chemicals, making milko scan minor very safe and inexpensive to use.

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Fig 3.4 Milko scan Tester

3.4.1 Features (a) Save timeWith FOSS Milko Scan Minor PC software, many of the time-consuming tasks related to milk analysis can be carried out by means of an external PC. The simplified procedures for data collection, calibration adjustment and data storage provides for greater efficiency and productivity in your daily work. (b) Data collectionAll results can automatically be collected, displayed and stored for calculation and adjustment of the basic calibrations. All results can be saved, printed and exported to other software programs. This ensures greater data security and reduces manual data entry. (c) Export and import of dataThe results can be exported for use in other software programs. Measured results can be imported and used in various sample sets. Results can be exported and printed on any printer via the PC. (d) EmulatorEmulator software is included in order to provide training and demonstrations and for fast and easy learning of the software. (e) CompatibilityThe Milko Scan Minor PC software is approved to run under Windows 2000 and Windows XP with service pack 2. (f) Local language optionGerman as well as English language is integrated in the PC software. AIET/ECE/PTS/23

EMT & Solar Panel Production (g) Sample IDSample ID can be entered before or after data collection.

3.4.2 Anaylazer Features (a) Pre-calibrated for milk and cream. (b) Automatic cleaning and zero-setting. (c) Unique FOSS Standard sample. (d) No hazardous chemicals. (e) Easy and cost-effective. (f) Analysis of cold samples.

3.4.3 PC SOFTWARE FEATURES (a) Automatic data collection (b) Calibration adjustment (c) Import/export of results (d) Print-out via PC

3.4.4 APPLICATIONS (a) Cow‟s milk (b) Skim milk (c) Buffalo milk (d) Goat‟s milk

3.4.5 PARAMETERS TO BE MEASURE (a) Fat (b)Protein (c) Lactose (d) Total solids (e) Solids –non-fat (f) Freezing point depression (g) Simple analysis of milk composition with milko-scan minor.

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CHAPTER4 RENEWABLE ENERGY DIVISION 4.1 INTRODUCTION The REIL entered into the solar photovoltaic industry in 1985.It started its operation by setting up a manufacturing facility for SPV modules and has expanded its area of operations through manufacture of balance of systems for large number of applications, utilizing its electronics product manufacturing facility. The company products are result of its own inhouse development efforts. The company has a capacity of 2MW per year on single shift basis. Solar photovoltaic based application products, sub-systems most of which were developed in-house, in SPV segment, the company manufacture SOV modules and application systems including domestic lighting system, street lighting system, chargeable power packs for the rural, telecom, railway & defence sectors.[4]

Fig 4.1 Solar panel

4.2 SILICON Silicon is important part of solar cell. Solar cell is made up of silicon. It has some special chemical properties, especially in its crystalline form. An atom of silicon has 14 electrons, arranged in three different shells. The first two shells, those closest to the center, are

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EMT & Solar Panel Production completely full. The outer shell is only half full, having only four electrons. A silicon atom will always look for ways to fill up its last shell (which would like to have eight electrons). To do this it will share electrons with four of its neighbour silicon atoms. It‟s like every atom holds hands with its neighbours, except that in this case, each atoms has four hands joined to four neighbours. Pure silicon is poor conductor of electricity because none of its electrons are free to move about, as electrons are in good conductors such as copper. Instead, the electrons are all locked in the crystalline structure.

Fig 4.2 Silicon Structure

4.2.1 Silicon In Solar Cell A solar cell has silicon with impurities other atoms mixed in with the silicon atoms. Consider silicon with an atom of phosphorous here and there, may be one for every million silicon atoms. Phosphorous has five electrons in its outer shell, not four. It still bonds with its silicon neighbour atoms, but in a sense, the phosphorous has one electron that doesn‟t have anyone to hold hands with. It doesn‟t form part of bond, but there is a positive proton in the phosphorous nucleus holding it in place. When energy is added to pure silicon, as in the form of heat, it can cause a few electrons to break free of their bonds and leave their atoms. A hole is left behind in each case. These electrons then wander randomly around the crystalline lattice looking for another hole to fall into. These electrons are called free carriers, and can carry electrical current. There are so few of them in pure silicon, however, that they aren‟t very useful. It turns out that it takes a lot less energy to knock loose one of our extra phosphorous electrons because they aren‟t tied up in a bond their neighbours aren‟t holding them back. As a result, most of these electrons do break free, and we have a lot more free carriers than we would have in pure

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EMT & Solar Panel Production silicon. The process of adding impurities on purpose is called doping and when doped with phosphorous, the resulting silicon is called N- type because of the prevalence of free electrons. N-type doped silicon is a much better conductor than pure silicon. That is only one part of solar cell is N-type the other part is doped with Boron; which has only three electrons in its outer shell instead of four, to become P-type silicon. Instead of having free electrons, P-type silicon has free holes. Holes carry the opposite (positive) charge, they move around just like electrons do.

4.2.2 N-Type Plus P-Type Silicon In photovoltaic module both N-type silicon and P- type silicon. Photovoltaic cell always has at least one electric field. Without an electric field, the cell wouldn‟t work and this electric field is forms when the N- type and P-type silicon are in contact. The free electrons in the N side looks all holes to fall into, the free holes on P side, and there‟s a mad rush to fill them in. Silicon was all electrically neutral. The extra electrons were balanced out by the extra protons in the phosphorous and the missing electrons (holes) were balanced out by the missing protons in the Boron. When the and electrons mix at the junction between N- type and P- type silicon, however, that neutrality is disrupted. At the junction electrons and protons are mix and form a barrier, making it harder and harder for electrons on the N side to cross to the P side.

Fig 4.2.2 N Type + P Type SI

4.3 TYPES OF PHOTOVOLTAIC SYSTEM PV systems are categorized into three types: autonomous, hybrid and grid-connected.

4.3.1 Autonomous system Autonomous systems are completely independent of other power sources. These type of systems are generally used to power remote homes, cottages or lodges as well as in applications such as remote monitoring and water pumping.

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EMT & Solar Panel Production In most cases, an autonomous system will require batteries for storage. Such systems are particularly useful and cost- effective for summer applications, when access to a site is difficult or costly, or when maintenance needs to be minimized.

4.3.2 Hybrid system Hybrid systems receive a portion of their power from one or more additional sources. In practice, PV modules are often paired with wind generator or a fuel-fired generator. Such systems usually require batteries for storage. They are most appropriate when energy demand is high (in the winter or year-round), when power must be available on demand.

Fig 4.3(b) Hybrid Power System

4.3.3 Grid-connected System It allow you to reduce your consumption from the electricity grid and, in some instances, to feed the surplus energy back into the grid. Since power is normally stored in the grid itself, batteries are not necessary unless you want some form of autonomous power during outages. These systems are used in buildings, homes or cottages.

Fig 4.3(c) Grid Connected System AIET/ECE/PTS/28


4.4 SOLAR PHOTO VOLTAIC CELL Solar cells, also called photovoltaic‟s (PV) by solar cell scientists, convert sunlight directly into electricity. Solar cells are often used to power calculators and watches. They are made of semiconducting materials similar to those used in computer chips. When sunlight is absorbed by these materials, the solar energy knocks electrons loose from their atoms, allowing the electrons to flow through the material to produce electricity. This process of converting light (photons) to electricity (voltage) is called the photovoltaic (PV) effect.

Fig4.4 Working of Solar photovoltaic cell To utilize this resource of energy, REIL use solar cells, which convert Solar Energy into Electrical Energy. A solar generates approximately 0.5 volts. Higher voltage and current are obtained by connecting these cells in series or in parallel.

4.4.1 Types Of Cell Solar cells can be categorized into five classes, depending upon their crystal structure. (a) High Efficiency Silicon Cell The purification of Si in this type of cell is very high. Hence its efficiency is high. It is used for laboratory devices having efficiency up to 30%. Example cadmium telluride efficiency is 28%. (b) Crystalline Silicon Cell It has high mechanical strength and these are less degraded with time. This is made using crystallization of Si around one Si crystal; hence it is called Single Crystalline Si Cell. It is

AIET/ECE/PTS/29

EMT & Solar Panel Production best suited for general purpose application. Float zone - efficiency is 23%CZ (commercial) ± efficiency is 13%.

Fig 4.4.1(b) Crystalline silicon cell (c) Multi-Crystalline Silicon Cell It is made by crystallization of Si around many crystals of silicon. It has less mechanical strength than single Crystalline Silicon material, efficiency of this cell is 12 %.

Fig 4.4.1(c) Multi-Crystalline Silicon Cell

(d) Amorphous Silicon Cell This cell doesn‟t have any Si crystal. Simply spreading a layer of p-type Si powder, and then N-type Si powder over it. Its mechanical strength is very low. Efficiency is 20%.

Fig 4.4.1(d) Amorphous Silicon Cell

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EMT & Solar Panel Production (e) Thin Film Silicon Cell It is made by very thin film of Si p-type and n-type materials and is used for special purpose. Efficiency is 25 %.

Fig 4.4.1(e) Thin Film Silicon Cell

4.5 TYPES OF DIFFERENT MODULES USED There is different type of solar module which I saw in REIL during my summer Vocational training period. A group of cells connected in series or in parallel and then properly laminated over a glass after curing is known as module. These modules are then fitted onto the areas receiving sunlight. More often these are placed so that upper part of the module is in the South Direction. Solar modules of different wattage and made as per orders and requirements. These are all designed to charge a 12-V battery. The approximation o/p voltage of a module is 16V-18V. Modules are made of following powers.

(a)18 Watt Module For making this, a total of 36 cells are connected in series. The o/p voltage

is

approximately 0.45V to 0.5V and the o/p current is approx. 2.2A. This 36 cell series is called a string the o/p of this string, when illuminated by the sunlight is found to be approx. 38watts. It has 4 rows, each containing 9 cells.

(b)75 Watt Module Here also, a total of 36 cells are connected in series, which is called string. But the cells used are Suido-Square having o/p voltage0.45V-0.5V &o/p current 4.5A. The o/p power of the string is found to be approx. 75 watts. It also has 4 rows, each containing 9 cells. (c)150 Watt Module These are also designed by Suido-Square cells. A total number of 72 cells are connected in series. The module has 6 rows and each row contain 12 cells.

AIET/ECE/PTS/31

EMT & Solar Panel Production Thus a total of 12*6=72 cells are used. The o/p voltage, current and power of each cell is the same as that of 75-watt module. The total power obtained is approx. 150 watts.[5]

4.6 CONSTRUCTION AND PRINCIPLE OF SOLAR CELL Solar cell is a simple p-n junction. It is made up of silicon, since in Si, the minority carrier concentration is low, hence they do not disturb the flow of electrons and holes, generated by the solar energy. Less charge carriers can get recombined due to low minority carrier concentration and we get higher value of current and power. For making p-n junction it is doped with gaseous Boron (p-type) from one side and solid phosphorous (n-type) from other side. The doping concentration is taken same for both the impurities. Due to different doping state difference of impurities (i.e. gaseous and solid), a one side shifted p-n junction is formed. This junction is shifted towards the n-side. Hence, the light is always made to incident at the n-side, so that the photons can reach the junction. When the high-energy photons reach the depletion region, they impart sufficient energy to an electron to break its covalent bond. This electron comes in conduction band and begins to behave free electron. At the same instant, a hole is also generated due to broken covalent bond.

Fig4.6 Construction of solar panel Hence, we can say that two charge carriers are generated by one high-energy photon. These carriers move to opposite direction due to potential barrier at the junction and constitute a AIET/ECE/PTS/32

EMT & Solar Panel Production current. One must condition of generation of mobile charge carrier is that the incident photon must have higher energy than the band gap of the semiconductor. The induced current is directly proportional to the surface area of the cell, at which the light is incident. A bare solar cell has some conducting lines made up of Silver oxide for collection of charge carriers from all the portions of the surface. These carriers are supplied to the bus bar. This is the place, from where the external terminals are connected by using copper strips. These cells are made up in different shapes and sizes, like circular, square, suedo-square, cut shaped etc. In these, Psuedo-Square is optimized size between circular and square to utilize most of the surface area & for less wastage in the process of shaping. The maximum conversion efficiency for laboratory devices is up to 20%, but for commercial cells, it lies between 10% to 15%.

4.7 SPV MODULE Photovoltaic‟s (or PV) is the field of technology and research related to the application of solar cells for energy by converting solar energy (sunlight, including ultra violet radiation) directly into electricity. Due to the growing demand for clean sources of energy, the manufacture of solar cells and photovoltaic arrays has expanded dramatically in recent years. Photovoltaic‟s is the direct conversion of light into electricity at the atomic level. Some materials exhibit a property known as the photoelectric effect that causes them to absorb photons of light and release electrons. When these free electrons are captured, an electric current result that can be used as electricity.

Fig 4.7 SPV Module Photovoltaic cells are connected electrically in series and/or parallel circuits to produce higher voltages, currents and power levels.. Photovoltaic panels include one or more PV

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EMT & Solar Panel Production modules assembled as a pre-wired, field-installable unit. A photo voltaic array is the complete power-generating unit, consisting of any number of P materials.

4.8 PROCESS FOR PRODUCTION OF SPV MODULE The

manufacturing process for Solar cell module is not much typical but requires a careful

handling since the sub-assemblies are costlier. A bare cell is expensive and hence requires a careful handling. The manufacturing process of a solar power module contains the following steps as-

PROCESS FLOW CHART FOR SPV PRODUCTION

INSPECTION STRING STORE

PRODUCTION COMPONENTS STORE

TABBING OF CELLS

INSPECTION AND REPAIRING

STRINGING

OK LAMINATION

LAY UP

CURING

VISUAL & ELECT. INSPECTION

TRIMMING

OK CHANNELLING

TERMINAL BOX FITTING AND SOLDERING

GOODS STORE

REGRADE

OK

FINAL INSPECTION

NOT OK

Fig4.8 Process Flow Chart of SPV Production

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4.8.1 Surface texturingForming pyramid like structure on Si wafer does it. This helps in decreasing the top surface reflection of solar radiation from the cell surface.

4.8.2 P-n junction formationTo a p type base of Si wafer, an n type usually phosphorus is diffused on it.

4.8.3 Back p+ junction formationThis is done by depositing an Aluminum layer and alloying it to the wafer at about 800degreeC

4.8.4 Antireflection layer depositionIt can be deposited before or after the formation of metal contacts. Usually any dielectric material having refractive index between Silicon & glass is used with an optimum thickness of 70nm.Materials used are Titanium Oxide, Tantalum oxide, Silicon Nitride and Aluminum oxide.

4.8.5 TabblingThis is the process of making terminals of a bare cell by soldering copper strips to the bus bar.

Fig 4.8.5 Tabbling

4.8.6 Row makingA row of nine cells is made by connecting positive surface of one cell to the negative surface of another cell.

Fig 4.8.6 Row making AIET/ECE/PTS/35


4.8.7 StringingFour rows are connected in series to give a total of 36 cells in series connection. This assembly is called a string and the process is called Stringing. STRING MAKING JIG

74W

5W

Fig 4.8.7 Stringing Process 4.8.7(a) String checking This String is checked visually for any kind of faults, which are as follows Reverse String  Dry Point  Dry Soldering  Loose Connection  Chip(Micro Broken)

4.8.7(b) Lay Up Lay Up is a process of placing laminating material to the either side of the string. The laminating materials are as listed  Top Glass (Toughened Glass)  E.V.A. (Ethylene Vinyl Acetate) sheet  Crane Glass  Polyester Taddler AIET/ECE/PTS/36


4.8.8 Lamination The above laminating materials are attached to the string on both sides by the process of lamination. This process takes place at 110degree C in laminating press. The module after Lay Up is placed in the press for 11minutes, which is equivalent to one cycle of the press. First five minutes, soaking takes place. This is the process to generate true vacuum in the module. Each air particle is stored from the inner part of the module. After these five minutes, heating takes place for three minutes. And for last three minutes, the heated module is pressed to attain a one-piece assembly.

Fig 4.8.8 Lamination Machine

4.8.9 Curing This process comes after the lamination to attain the full strength of laminating material. for this, the module is placed into 120degree temperature for 20 minutes.

Fig 4.8.9 Curing Machine

AIET/ECE/PTS/37


4.8.10 Trimming The resultant module from curing process has some extra laminating materials. These materials are then cut and the final module is then obtained. 4.8.11 Electrical Inspection This inspection is done to check the output performance of the module 4.8.12 Channeling Now to provide structural support to the module, channels are fixed around it. These channels prevent any damage to the module. A terminal box is also fitted for external connections and for mounting safety diodes and then the final product is cleaned and sent to and sent to he finished goods store.[38]

4.9 FEATURES OF SPV CELLS (a) High efficiency monocrystalline Silicon Solar Cells connected in series. (b) Lamination using TEDLAR, Crane glass and EVA provides environmental protection. (c) Solar cells laminated between UV resistant polymer (EVA) and high transmitivity toughened glass surface. (d) Rugged weather proof nylon terminal box for output connections. (e) Anodized aluminum frame provides structural support for mounting and shock resistance. (f) Manufactured to stringent quality standards and tested to withstand adverse environmental conditions.[5]

Fig 4.9 Solar Cell Uses

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4.10 APPLICATIONS OF SPV  Domestic lighting systems  Street lighting  Water pumping  Battery charging  Community TV system  Microwave repeater station  Railway signaling and lighting systems  Rural radio phones and exchanges  Offshore platforms  Desalination plants  Cathodic protection systems  Portable lantern  Power pack for village electrification  Crop sprayer  Sign boards & Glow signals

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CHAPTER 5 QUALITY ASSURANCE & ENGINEERING DEPARTMENT 5.1 INTRODUCTION Every company has a cell for checking the quality of its good, so that the consumers can use the product without any difficult for a long time. REIL has a department for quality assurance and control. I also went through this department where I saw the various function of this department. In REIL, Q.A. department has two major operations. (a) Solar Module Checking. (b) EMT Checking.

5.2 INWARD GOODS CHECKING The raw material bought by REIL for the production of EMT and Solar Module are firstly checked, if they are faulty or not. If they are faulty, they are returned otherwise forwarded to manufacturing cell. It called inward goods checking. In this type of checking, out of a group of say 60 pieces, 5 pieces are checked randomly. If they all are found to be good, then all are passed to production department, and if not then, all pieces are checked one by one. The faulty pieces are forwarded for replacement. Subassembly Quality Control: This department also checks the quality of subassemblies, made by the raw goods by REIL. Final Goods Inspection: After the final product is obtained; it is again checked for quality control.

5.2.1 SPV Checking It has three major phases. (a) Inward Goods Checking- first of all, the bare cells are checked for required quality. (b) String Checking- After making string, it is checked visually. The main faults in a string are

Reverse String.



Loose Connection.



Chip ( Micro broken).

(c) Electrical Inspection- This is used to check the performance of the module under normal working condition. AIET/ECE/PTS/40


CHAPTER 6 INDUSTRIAL PRODUCTS

6.1 SPOT BILLING MACHINE The Spot Billing Machine (SBM) is a Hand Held Computer, in which the program is stored along with all the relevant data, for issue of electricity bills, right at the customer premises, immediately after the meter reading is read and input to SBM. The storage of program and data is done through a Personal Computer (Host PC) and is called pre-journey configuration for the specific meter-reader route, user-connection record including type of connection, applicable tariff, previous reading, past payments etc. The master data pertaining to the tariff tables, type of connection, consumer profile are stored on the Host PC, and made available for uploading on to the SBM at the time of configuration. Once the pre-configuration is over the SBM is ready for field operations. The meter-reader reports at the consumer site, accesses the customers account on SBM and record the current reading. On the basis of the last reading and tariff structure, a bill would be generated instantly. Payment in non-cash mode can also be collected then and there. In such case, the receipt would also be generated.

Fig 6.1 Spot billing machine AIET/ECE/PTS/41

EMT & Solar Panel Production The payment could be collected through non-cash modes. A collection report can be prepared at the end of trip. After a journey is over the transaction data files are transferred from SBM to the Host PC, over a communication cable connected to serial communication port. The SBM requires about three hours for full charging after which it can be used continuously for 7-8 hours. A pre-implementation study is a pre-requisite for such projects, to identify the system requirements and user requirements. The customization can be done as per the user requirements.

6.1.1 Specifications (a) High Speed CPU (b) 256 KB program memory (c) 4 MB data memory (d) Real Time Clock (e) LCD display unit (4 rows x 20 character) with backlight (f) 30 Keys soft silicon rubber Keypad (g) High speed serial port / program port (115 Kbps) (h) Built-in 24 column Impact printer (i) Built in 2.2 AH Lithium-Ion or 1.7 AH Ni MH battery

6.1.2 Features (a) The bill is immediately generated. (b) The collection of dues, through non-cash instruments, is performed in the field. (c) Variety of reports can be prepared. (d) Utility Bill with all relevant details. (e) Receipt against the Bill. (f) Day end Collection report. (g) Duplicate receipt.

6.2 Solar Water Pumping System Solar photovoltaic water pumping system is modular, flexible and are of two basic types i.e. Shallow well type & Deep well type.The pumping system are extremely rugged, maintenance free & do not need any other external source of power. D.C. power is generated at site itself and fed to the pump. They are ideally suitable for those are as where AIET/ECE/PTS/42

EMT & Solar Panel Production conventional grid supply is either erratic or non-existent. Also SPV pumps require only one time investment with no recurring cost and have a long life.[6] 6.2.1 Applications (a) Drinking water. (b) Irrigation. (c) Agriculture related use. (d) Horticulture. (e) Animal Husbandry. (f) Poultry farming. (g) High value corps

6.3 SPV RAILWAY SIGNALING SYSTEM SPV system provides reliable and economical power for energizing the signal motor and lamps at isolated railway signals that are far from grid power. REIL has supplied and installed over 340 SPV Signaling Systems on various sections of Western Railways. These systems are working satisfactorily under adverse climatic conditions of very high temperature, dust-storms, etc. REIL's SPV Modules are approved by R.D.S.O., Ministry of Railways vide their approval No. STS/E/Cell Solar.

Fig 6.3 Railway signalling system

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6.3.1 Specifications Each system consists of the following: (a) SPV Module - 35Wp (b) Battery - 12V, 80AH (c) Signaling PCB to energies front & back bulb with automatic dusk to dawn switching (d) Charge control unit.

6.3.2 Features (a) Automatic switching and hence unmanned operation. (b) Optimal use of grid power. (c) Energy saving up to 30%. (d) Enhancement of pole-lamp life. (e) Highly efficient, reliable and economical. (f) System design can take care of any grid load / safety precautions. (g) No seasonal time setting required. (h) Highly weather proof and totally maintenance free sensor.

6.4 SPV Dusk-Dawn system Solar Photo Voltaic (SPV) Dusk Dawn System is an energy saving device used for automatic switching of street lighting systems, making proper use of grid power and increasing the life of the lamps by switching the street lights for a optimum period .The system is highly reliable and efficient for years of continuous flaw-less operation. The system's operation is based on sensing the ambient light level which actuates the electronic controller to switch ON the street lights in the evening and switch OFF in the morning.

Fig 6.4 SPV dusk-dawn system AIET/ECE/PTS/44

EMT & Solar Panel Production The sensor is totally maintenance free and encapsulated in an environment proof housing making it more reliable even in adverse atmospheric conditions. The system has the advantage of automatic setting of switching timings irrespective of whether it is winter or summer, thus making it a totally unmanned operation. Once a setting for a particular darkness level is done, it remains unchanged throughout the year.

6.4.1 Features (a) Automatic switching and hence unmanned (b) Optimal use of grid power. (c) Energy saving up to 30%. (d) Enhancement of pole-lamp life. (e) Highly efficient, reliable and economical. (f) System design can take care of any grid load / safety precautions. (g) No seasonal time setting required. (h) Highly weather proof and totally maintenance free sensor. (i) Protection against line to line, line to neutral & line to earth fault. (j) Manual by-pass in case of system failure.[7]

6.5 SPV DOMESTIC LIGHTENING SYSTEM This system provides un-interrupted light and is completely noiseless, smoke-free andfree from fire hazards. The independent lighting system consisting of 2 CFL fixtures, astorage battery powered by the SPV Module provides 4 hours of light per day. Duringday time SPV module charges the battery. At night battery operates CFL bulbs and provides light in remote areas.[7]

Fig 6.5 SPV Domestic lightening System AIET/ECE/PTS/45

EMT & Solar Panel Production 6.5.1 Applications (a) Rural areas which have no grid supply. (b) Farm Houses (c) Urban house holds which face frequent power cutsd. (d) Out-of-the-way holiday locations. (e) Holiday cottages & caravans.

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CONCLUSION

The summer training of 4 weeks in REIL played an important role to develop myself. It was a golden opportunity for me to get the practical knowledge and hands on experience from the things about which I had theoretical knowledge from the course curriculum. Hence I can say that taking training in such an organization proved to be very beneficial for me. All those that we read in our books theoretically, by this training I observed all those practically. I learnt quite a lot about agro-electronics products such as Electronic Milk Tester and also renewable energy source as SPV module. The first phase of training has proved to be quite fruitful. It provided an opportunity to encounter with such important machines. The architecture of company has various units. They are linked and controlled working of whole plant is making the student realize that engineering is not just learning the structural description and working of various machines. But the greater part is planning proper management. I am very grateful to those persons who helped directly & indirectly in the successful completion of this practical training and this will surely be fruitful in future.

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REFERENCE TABLE

S.No [1] [2] [3] [4] [5] [6] [7]

Link Name www.reiljp.com www.scribd.com www.reilsolar.com

http://www.inelrel.com/renewable_energy.html www.enfsolar.com/directory/panel/2559 www.reiljp.com/pdf/dpemt.pdf http://www.solarserver.com/solar-magazine/solar-news/top-solarnews.html

Page No. 02 07 38 25 32 43 45

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BIBLIOGRAPHY SITES 

http://www.solarserver.com/solar-magazine/solar-news/top-solar-news.html



www.reiljp.com/pdf/dpemt.pdf



www.enfsolar.com/directory/panel/2559



www.reiljp.com



www.scribd.com

 http://www.webstatschecker.com/stats/keyword/reil_jaipur 

www.reilsolar.com



http://www.inelrel.com/renewable_energy.html

AIET/ECE/PTS/49

a report on emt & solar panel production REIL

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