...Necessity of D.C. Motor Starter At starting, when the motor is stationary, there is no back e.m.f. in the armature. Consequently, if the motor is directly switched on to the mains, the armature will draw a heavy current (Ia = V/Ra) because of small armature resistance. As an example, 5 H.P., 220 V shunt motor has a full-load current of 20 A and an armature resistance of about 0.5 . If this motor is directly switched on to supply, it would take an armature current of 220/0.5 = 440 A which is 22 times the full-load current. This high starting current may result in: (i) burning of armature due to excessive heating effect, (ii) damaging the commutator and brushes due to heavy sparking, (iii) excessive voltage drop in the line to which the motor is connected. The result is that the operation of other appliances connected to the line may be impaired and in particular cases, they may refuse to work. In order to avoid excessive current at starting, a variable resistance (known as starting resistance) is inserted in series with the armature circuit. This resistance is gradually reduced as the motor gains speed (and hence Eb increases) and eventually it is cut out completely when the motor has attained full speed. The value of starting resistance is generally such that starting current is limited to 1.25 to 2 times the full-load current. 5.8 Types of D.C. Motor Starters The stalling operation of a d.c. motor consists in the insertion of external resistance into the armature...
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...Starting and Ignition Systems Gas turbines unlike piston engines employ a continuous combustion process to provide the heat input to their working cycle. Once ignited the fuel burns continuously until the engine is shut down, at this point the combustion is extinguished by cutting off the fuel supply. When a gas turbine is started, a means of igniting the fuel is required, in most cases this is provided by an electric spark. One or more ignitor plugs are placed in the combustion chamber usually close to a fuel burner nozzle. When the fuel is switched on the spray from the burner reaches the plug and ignites. Most small gas turbines only have one ignitor plug, but in some cases when an engine is constructed with an annular combustion chamber, two are fitted at opposite sides of the combustion chamber. Ingination Like piston engines GTEs are also fitted with dual ignition systems. These are rated in Joules (watt per second or w/s). The life of the igniters is extended by limiting the amount of energy required. So if continuous use is necessary, for example in heavy rain, snow and or turbulence, power output is reduced. Most systems have low and high output igniters and both are used during start where the low output igniter is used for continuous use. Modern electronic igniter systems can be regulated in energy output (J) as required High Tension Ignition This process is not dissimilar to piston engine ignition systems. A step up transformer or "ignition coil" provides...
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...charging system – system that generate electricity used in the vehicle and charge the battery ignition system – system to ignite the compressed air-fuel mixture ignition switch – main switch of the ignition Battery: battery – the battery is the primary “Source” of electrical energy of a vehicle. it stores chemicals not electricity. two different types of lead in an acid mixture react to produce electrical pressure. chemicals inside the battery: * lead or sponge lead (negative plate) * lead peroxide (positive plate) * sulfuric acid and water (electrolyte) battery functions: 1. engine off – battery energy is used to operate the lighting system and accessory system 2. engine starting – battery energy is used to operate starter motor and provide current for ignition system during cranking 3. engine running – battery energy can be needed when the electrical load exceed the supply from charging system types of battery: * conventional type * low maintenance battery * high maintenance battery * free maintenance battery * hybrid battery * recombination battery battery service: * cleaning * jump-start * charging * adding water * testing battery terminals: * side terminals * post or top terminals * “L” terminal battery construction: 1. case – container which holds and protects all battery components and electrolyte, separates cells and provide space at the for sediments 2. cover – permanently sealed...
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...Final Investigatory Project for Group 5 I. Problems and Setting A. Introduction Batteries, years ago, have taken the world by a storm and have since than became a necessity in one’s household. Sadly, even though they are tremendously useful, batteries have drawbacks, such as semi- affordable costs, limited shelf life and pollution. Our group had an idea on how to make an alternative to this that would not only work like the real thing but would also be healthy to our environment and light in our pockets. This idea turned out to be realty and became the main goal of our Investigatory Project. B. Problems Finding an item that is easy to obtain and at the same time affordable, simple and earth- friendly is not an easy task. After a lot of thought, our group decided to use one of the objects that is almost always present in our daily lives: fruits and vegetables. Will these everyday materials such as apples, bananas, oranges, lemons and potatoes conduct electricity? Well, let’s see about that. C. Hypothesis A circuit is made up of a path, a source and a load. We believe that we should connect them with a (+) and a (-) wire so that the flow will be even with no reverse polarity. The load we thought of using was a battery- operated clock, one of the most common materials found in almost everyone’s household. We believe that it would work because the organic materials we will use have electrolytes that flow freely on its own. Thus, it will flow into conductors to make...
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...Final Investigatory Project for Group 5 I. Problems and Setting A. Introduction Batteries, years ago, have taken the world by a storm and have since than became a necessity in one’s household. Sadly, even though they are tremendously useful, batteries have drawbacks, such as semi- affordable costs, limited shelf life and pollution. Our group had an idea on how to make an alternative to this that would not only work like the real thing but would also be healthy to our environment and light in our pockets. This idea turned out to be realty and became the main goal of our Investigatory Project. B. Problems Finding an item that is easy to obtain and at the same time affordable, simple and earth- friendly is not an easy task. After a lot of thought, our group decided to use one of the objects that is almost always present in our daily lives: fruits and vegetables. Will these everyday materials such as apples, bananas, oranges, lemons and potatoes conduct electricity? Well, let’s see about that. C. Hypothesis A circuit is made up of a path, a source and a load. We believe that we should connect them with a (+) and a (-) wire so that the flow will be even with no reverse polarity. The load we thought of using was a battery- operated clock, one of the most common materials found in almost everyone’s household. We believe that it would work because the organic materials we will use have electrolytes that flow freely on its own. Thus...
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...Revistas Científicas de América Latina, el Caribe, España y Portugal Sistema de Información Científica Duangporn Kantachote, Pakorn Prachyakij, Wilawan Charernjiratrakul, Metta Ongsakul, Yodsawee Duangjitcharoen, Chaiyavat Chaiyasut, Teruhiko Nitoda, Hiroshi Kanzaki Characterization of the antiyeast compound and probiotic properties of a starter Lactobacillus plantarum DW3 for possible use in fermented plant beverages Electronic Journal of Biotechnology, vol. 13, núm. 5, 2010, pp. 1-15, Pontificia Universidad Católica de Valparaíso Chile Available in: http://www.redalyc.org/articulo.oa?id=173318799002 Electronic Journal of Biotechnology, ISSN (Electronic Version): 0717-3458 edbiotec@ucv.cl Pontificia Universidad Católica de Valparaíso Chile How to cite Complete issue More information about this article Journal's homepage www.redalyc.org Non-Profit Academic Project, developed under the Open Acces Initiative Electronic Journal of Biotechnology ISSN: 0717-3458 http://www.ejbiotechnology.info DOI: 10.2225/vol13-issue5-fulltext-1 Characterization of the antiyeast compound and probiotic properties of a starter Lactobacillus plantarum DW3 for possible use in fermented plant beverages Duangporn Kantachote1 1 · Pakorn Prachyakij1 · Wilawan Charernjiratrakul1 Metta Ongsakul · Yodsawee Duangjitcharoen2 · Chaiyavat Chaiyasut2 Teruhiko Nitoda3 · Hiroshi Kanzaki3 1 Department of Microbiology, Faculty of Science, Prince of Songkla University, Thailand...
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...BMW 3- & 5-Series Service and Repair Manual A K Legg Models covered 3-Series (E30) 316 (83 to 88), 316i (88 to 91), 318i (83 to 91), 320i (87 to 91), 325i (87 to 91). Also Touring and Convertible versions of these models 5-Series (E28) 518 (81 to 85), 518i (85 to 88), 525i (81 to 88), 528i (81 to 88), 535i (85 to 88), M535i (85 to 88) 5-Series (E34) 518i (90 to 91), 520i (88 to 91), 525i (88 to 91), 530i (88 to 91), 535i (88 to 91) Engines covered 1596 cc, 1766 cc, 1795 cc, 1990 cc, 2494 cc, 2788 cc, 2986 cc & 3430 cc Does not cover Diesel, dohc or V8 engines, or four-wheel-drive models LAE MIMI and Larry Warren (1948-256-11AA3) © Haynes Publishing 1997 A book in the Haynes Service and Repair Manual Series ABCDE FGHIJ KLMNO PQRST 123 Printed by J H Haynes & Co. Ltd, Sparkford, Nr Yeovil,Somerset BA22 7JJ, England Haynes Publishing Sparkford, Nr Yeovil, Somerset BA22 7JJ, England Haynes North America, Inc 861 Lawrence Drive, Newbury Park, California 91320, USA Editions Haynes S.A. 147/149, rue Saint Honoré, 75001 PARIS, France Haynes Publishing Nordiska AB Box 1504, 751 45 Uppsala, Sweden All rights reserved. No part of this book may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording or by any information storage or retrieval system, without permission in writing from the copyright holder. ISBN 1 85960 236 3 British Library Cataloguing in Publication Data A catalogue record for this book is...
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...Product description: Now a day, automotive battery is also used for IPS, UPS service. The batteries that Rahimafrooz produces are suitable for both automotive and home appliances use. An automotive battery is a type of rechargeable battery that supplies electric energy to an automobile. It is used power the starter motor, the lights, and the ignition system of a vehicle’s engine. An automotive battery may also be a traction battery used for the main power source of a vehicle. Now a day, automotive battery is also used for IPS, UPS service. The batteries that Rahimafrooz produces are suitable for both automotive and home appliances use. Automotive SLI batteries are usually lead-acid batteries, and are made of six galvanic cells in series to provide a 12 volt system. Each cell provides 2.1 volts for a total of 12.6 volt at full charge. Heavy vehicles such as highway trucks or tractors, often equipped with Diesel engines, may have two batteries in series for a 24 volt system, or may have parallel strings of batteries. Lead-acid batteries are made up of plates of lead and separate plates of lead dioxide, which are submerged into an electrolyte solution of about 35% sulfuric acid and 65% water. This causes a chemical reaction that releases electrons, allowing them to flow through conductors to produce electricity. As the battery discharges, the acid of the electrolyte reacts with the materials of the plates, changing their surface to lead sulfate. When the battery is recharged,...
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...Programmable Logic Controllers: Programming Methods and Applications by John R. Hackworth and Frederick D. Hackworth, Jr. Table of Contents Chapter 1 - Ladder Diagram Fundamentals Chapter 2 - The Programmable Logic Controller Chapter 3 - Fundamental PLC Programming Chapter 4 - Advanced Programming Techniques Chapter 5 - Mnemonic Programming Code Chapter 6 - Wiring Techniques Chapter 7 - Analog I/O Chapter 8 - Discrete Position Sensors Chapter 9 - Encoders, Transducers, and Advanced Sensors Chapter 10 - Closed Loop and PID Control Chapter 11 - Motor Controls Chapter 12 - System Integrity and Safety Preface Most textbooks related to programmable controllers start with the basics of ladder logic, Boolean algebra, contacts, coils and all the other aspects of learning to program PLCs. However, once they get more deeply into the subject, they generally narrow the field of view to one particular manufacturer's unit (usually one of the more popular brands and models), and concentrate on programming that device with it's capabilities and peculiarities. This is worthwhile if the desire is to learn to program that unit. However, after finishing the PLC course, the student will most likely be employed in a position designing, programming, and maintaining systems using PLCs of another brand or model, or even more likely, many machines with many different brands and models of PLC. It seems to the authors that it would be more advantageous to approach the...
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...CHAPTER-1 INTRODUCTION 1.1 INTRODUCTION TO SOLAR ENERGY Fig. 1.1(a) Block Diagram of Photovoltaic System Renewable energy is rapidly gaining importance as an energy resource as fossil fuel prices fluctuate. At the educational level, it is therefore critical for engineering and technology students to have an understanding and appreciation of the technologies associated with renewable energy. One of the most popular renewable energy sources is solar energy. Many researches were conducted to develop some methods to increase the efficiency of Photo Voltaic systems (solar panels). One such method is to employ a solar panel tracking system. This project deals with a microcontroller based solar panel is always able to maintain a perpendicular profile to the sun’s rays. Development of solar panel tracking systems has been ongoing for several years now. As the sun moves across the sky during the day, it is advantageous to have the solar panels track the location of the sun, such that the panels are always perpendicular to the solar energy radiated by the sun. This will tend to maximize the amount of power absorbed by the PV systems. It has been estimated that the use of a tracking system, over a fixed system, can increase the power output by 30%-60%. The increase is significant enough to make tracking a viable preposition despite of the enhancement in system cost. It is possible to align the tracking heliostat normal to sun using electronic...
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...Course code: 15MA101 | Engineering Mathematics | L | T | P | C | | | 3 | 1 | - | 4 | Course Objectives | To train the students in basic mathematics essential for modeling and solving engineering problems. | Course Outcomes | 1. An ability to apply knowledge of mathematics, science and engineering. 2. An ability to identify, formulate and solve engineering problems | Differential Calculus: Review: Functions and graphs, Limits and Continuity, Differentiation, Maxima and minima of a function, Rolle’s Theorem, Mean Value Theorem. Indeterminate forms and L'Hopital's rule, Infinite sequences and series, Power series, Taylor's and Maclaurin's series, Convergence of Taylor's series, Error Estimates, Polar coordinates and Polar equations. Functions of two or more real variables, Partial derivatives of second and higher order, Euler’s theorem on homogenous function, Total derivatives, Differentiation of composite and implicit functions, Change of variable, Jacobians, Maxima and minima of functions of two or more variable, Lagrange’s method of undetermined multipliers. Integral Calculus: Estimating with finite sums and limits of finite sums, Definite integral, The fundamental theorem of calculus, Trigonometric substitutions, Integration by reduction formula for powers of some trigonometric functions, Improper integrals, Beta and Gamma integrals. Double integrals, Triple...
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... Servicing Lead Acid Battery Aizat Hizami Bin Abu Bakar, Unikl MIAT, aizathizami@gmail.com Abstract—These articles is about servicing one of the type of battery which is Lead Acid Battery. In time, batteries’ capacity may decrease due to the way we handle the battery thus proper way of servicing and charging of the battery is necessary. The capacity of the battery can be maintain through the process of servicing below. Index Terms—Battery I. INTRODUCTION O NE of the most important aspects of battery servicing is to keep the battery clean and all the terminals tight and free of corrosion. If any corrosion exists on the battery terminals or within the battery box, it should be removed. One way to do this is by scrubbing the battery box and the top of the battery with a soft bristle brush and a solution of sodium bicarbonate (baking soda) and water. When washing the top of the battery, avoid getting any baking soda in the cells since it neutralizes the electrolyte. After the battery and box are clean, rinse them with clean water and dry thoroughly. Coat the battery terminals with petroleum jelly or general purpose grease, and touch up any paint damage to the battery box or adjacent area with an acid-resistant paint. A lead acid battery goes through three life phases, called formatting, peak and decline are shown in Figure 1. Fig. 1. Cycle life of a battery In the formatting phase try to imagine sponge-like lead plates that are being exposed to a liquid. Exercising...
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...control and automation. They have become a fast replacement of present workers army which is engaged in processing and assembling of the factory. In this fact developing society, electronic has come to stay as the most important branch of Engineering. Electronic devices are being used in almost all the industries for quality control and automation. They have become a fast replacement of present workers army which is engaged in processing and assembling of the factory. 2. Problem statement: The objective of this project is to make a device with the help of PLC which can control automatically the devices connected with it, the PLC we are using is Siemens LOGO module, we control the street light, home appliances, Lamp Flasher, and star delta starter. The PLC helps us in automatic control of devices with its output signal; we can also provide the time delay using timers. 1 3. Purpose of the Project: An engineer discovers new ideas and identifies opportunities in various sectors of national economy. He explores the possibilities of starting adventures infield of agriculture, trade, industry, transport and communication etc. An engineering project is a combination of numerous activities on the part of entrepreneurs, organizers, designers, workers and etc. The engineer is the key element in any project work and it is not possible to attain success for every engineer. An engineer should possess certain qualities and characteristics to achieve success...
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...RESEARCH STARTERS ACADEMIC TOPIC OVERVIEWS Four Stages of Social Movements Social Movements & Collective Behavior > Four Stages of Social Movements Table of Contents Abstract Keywords the four stages of social movements. The four stages of social movement development are emergence, coalescence, bureaucratization, and decline. The Decline stage can result from several different causes, such as repression, co-optation, success, failure, and mainstream. The four stages of development model can be applied to understand how movements form, grow, and dissipate. It has limitations, however, in its application to new social movements and movements that are not rooted in political action. Despite these limitations, the four stages model is still highly useful in understanding collective action and provides a useful frame of analysis for sociologists considering social movements and their effects in the past and present. Overview What is a Social Movement? Four Stages of Social Movements Stage 1: Emergence Stage 2: Coalescence Stage 3: Bureaucratization Stage 4: Decline Repression Co-optation Success Failure Establishment with Mainstream Overview There have been many social movements throughout history that have dramatically changed the societies in which they occurred. There have been many failed social movements as well. Throughout the history of the United States alone there have been a number of important and notable social movements. These movements have varied widely...
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...Types of Foundation The foundation is the base for the constructed building and as such is required to carry out several functions as follows: 0 The foundation should safely sustain and transmit to the ground the combined dead and imposed loads of the building without resulting in any settlement or other movement of the building or any adjoining works. 1 Foundations should be deep enough or be constructed in such a way as to avoid damage by the swelling, shrinkage or freezing of the subsoil. 2 The foundation should be capable of resisting attack by chemicals such as soluble salts or other deleterious materials present in the subsoil. Choice of Foundation The designer is required to choose the most appropriate type of foundation taking account of two main factors: * The total dead and imposed loads of the building * Possibility of subsoil movement The foundation design should take account of any subsoil movement caused by changes in the moisture content of the subsoil. These movements are normally changes in volume when the subsoil becomes either wet or dry and will normally occur near the surface of the soil . Similar volume changes can occur due to water freezing and expanding in a soil (this is called frost heave). Note the average foundation loading for a two-storey domestic dwelling is normally between 30 and 50 kN per metre. Foundation Types The most common foundation types used in low-rise domestic and light industrial buildings...
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