sl technological sevices

                                 CHAPTER 1 INTRODUCTION 1.1 Background of Study Power instability in developing countries creates the need for automation of phase selector or alternatives source of power to back the utility supply. Most industrial and domestic application are dependent on power supply and if the process of change over is manual ,not only considerable time wasted but also the device or machine may get damaged from human error during the change over connection incurring massive losses Here an automatic three phase selector can be installed in residential and office premises where single phase equipment are used .when any of the mains phase line fails ,it automatically select the available phase line out of the three phase line or backup lines.   Get complete materials here 

                                    CHAPTER ONE INTRODUCTION Today,smoke detection device is recognized to play an essential role in providing fire safety in buildings, to protect people, property and contents.  Today’s view is in stark contrast to the view of about 50years ago when automatic detection was rarely provided in buildings.  The change in attitude has been the result of a series of significant fire incidents and research developments. However significant fires resulted in the loss of numerous lives and/or involved substantial damage to property and contents and the lack of early detection was identified as a major factor in the out come of the fire thus the need to smoke detector in a building is of out most value. A smoke detector is a device that senses the presence of smo...

                         1.0   INTRODUCTION The design and construction of microcontroller based digital display is that which display information or data programmed on it with  series of instruction. It is an image sequence of an LED display used for displaying decimal numerals and also the alphabet that is an alternative to the more complex dot matrix display, which is becoming popular for transmission of information to large group of people quickly. It usually consists of smaller module (dot matrix units) illumination display arranged together to form a larger screen, each module usually consisting of 8 by 8 matrix of LEDs. On which the signal from the micro controller is interfaced with the row of the dot matrix  and the column is been interfaced with the shift register circuit. Comparatively, liquid crystal displays (LC...

                                                  CHAPTER 1  1.0       INTRODUCTION In our day to day domestic operations as well as industrial process operations, we constantly make use of different types of Electrical/electronic Equipment; all of which require one form of power supply or the other to render them operational. One of such forms of power supply is the INVERTER. Simply put, an inverter is an Electrical device (power Source) used to meet the need where ac power is required from a primary power source e.g. Battery or solar panels. This project gives a step–by–step account of how this design of A 24V DC – 220V AC, 2.5KVA INVERTER POWER SYSTEM WITH UNDER VOLTAGE AND OVER LOAD PROTECTION) was accomplished. It is comprised of five (5) chapters such that each of...

                                           CHAPTER ONE INTRODUCTION An automatic voltage regulator (AVR) is a regulating unit that’s controls a system to achieve a set desired output. This system comprises of a comparator unit, which is also known as decision making unit, the rectification unit, the timing unit   and the voltage cutoff unit each of this unit mentioned above perform different operations. When ac voltage enters the AVR unit the timing unit springs up automatically, the essence of the timing unit is to allow the decision unit (op amp and NAND gate IC) to compare the input voltage from the unit to give the necessary signal on which transformer tap  to select, the is achieved with the aid of a switching relay that is connected to the tran...

INTRODUCTION: Power failure in general does not promote development to public and private sector. The investor do not feel secure   to come into a country with constant or frequent power failure thus this limit the development of industries . However Instability of power supply is a major challenge in developing countries like Nigeria. The need for alternative power supply makes the switching of load between two or more power sources imperative.     The   smart automatic changeover eliminates the need for manual or human intervention by sensing mains supply and switching to an available source. Automation eliminates the delay and the cost of inefficiency associated with manual operation.      This   device automatically switches between the power sources(PHCN and GENERATOR) and also indicates if utility power is restored when an alternative power is in use.     This paper presents the design and implementati...

                            INTRODUCTION : THE heart of this project is the microcontroller with value pic16f877a  of microchip by manufacturer and 8bit in terms of bit category It has 40pins of which pin 12&30 are vdd ,pin 13&31are vss and pin 1  is MCLR  which must be connected in respect to vcc For the program loaded into the program memory to be executed  the must be an oscillator with frequency stability thus a crystal oscillator with 8Mhz is choosen and according to the pdf 30pf capacitor must be connected to it as depicted in the pdf The remaining 35 pins can either be set as input or output ports by the use of the TRIS key word The automatic water control have a power section which consist of transformer, bridge diode ,capacitor and the voltage regulator . The transformer takes an input voltage of 220vac...

                                        CHAPTER 1 1.0      INTRODUCTION           Speed control is the intentional changing of the speed of a motor for a specific purpose or work process. This was done manually by an operator before now, but with the advent of powerful electronic elements like thyristor, Bipolar Junction Transistor (BJT), Insulation Gate Bipolar Transistor (IGBTs), Metallic Oxide Semiconductor Field Effect Transistor (MOSFET), etc it is now possible to actualize this speed control automatically.     There are two broad classification of the speed control of a D.C motor:   Armature-Voltage control scheme and field flux control scheme. To control the motor above its based speed, the field-flux co...

SINGLE PHASE POWER CONTROL Abstract POWER control can be achieved by changing firing angle of THYRISTOR with the help of micro controller PIC16F877A. Varying the POWER   of an induction motor by means of changing firing angle of any thyristor is very widely used method. One very nice example is fan regulator in which a fan motor is an AC motor used and its speed is varied using THYRISTOR method. A zero crossing detector circuit is used here to interrupt PIC16F877A after every 10 ms. After getting an interrupt pic16f877a will fire THYRISTOR after some delay from 1 to 9 ms. This will cut the current supplied to motor and so the speed of motor will reduce. Thus by varying the delay after which the THYRISTOR is triggered one can change the speed of motor. Main circuit is a combination of two sub circuits. 1.    Zero crossing detector circuit 2.    Firing angle control circuit Zero crossing detector circuit: Connections: From the circui...

 Auto Intensity Control Of Street Lights  Designing Of Dc Motor Speed Control Unit  Auto Power Supply Control System From 4 Different Sources (Solar, Mains, Generator & Inverter) To Ensure No Break Power  Thyristor Power Control Using  IR Remote  Thyristor Controlled Power For Induction Motor  Industrial Power Control By Integral Cycle Switching Without Generating Harmonics  Thyristor Firing Angle Controller Based Industrial Battery Charger  Ultra Fast Acting Electronic Circuit Breaker  Design Of Sensing Soil Moisture Content By Auto Irrigation System Automatic Star Delta Starter For Induction Motor Using Relays And Adjustable Electronic Timer   Remote Control Device Induction Motor With Bidirectional Rotation   Precise Digital Temperature Control     Line Following Robotic Vehicle  Tv Remote Operated D...