CHAPTER ONE
1.0INTRODUCTION
Our ability to measure a quality determines our knowledge of that quantity, the measurement of electrical quantities or other parameters in terms of electrical quantities is essential to our everyday life. Hence there is need is to have a through knowledge of electrical instrumentation and measuring systems.
Instrumentation is the technology of measurement in all branches of sciences, engineering and technology and are mainly use to monitor a process or operation as well as controlling (victor, 2009). However the term instrument in its wider sense may be categorized as indicating, recording and controlling instruments. As it concerns the topic of our research, indicating instrument is to be intensively considered. Indicating instruments are those instruments which indicate the value of the quantity that is being measured at the time at which it is measured. Such instrument according to Theraja (2000), consist essentially of a pointer which moves over a calibrated scale and which is attached to a moving system pivoted in jewelled bearings. These indicating instruments are Ammeter, voltmeter, wattmeter, galvanometer, meter bridge etc which measures current, voltage, power, smaller values of currents and resistances respectively.
Our interest this work is to construct a meter bridge that will be useful in the laboratory. To achieve this target requires a consideration and understanding of the principle of operation of a Wheatstone bridge and a potentiometer.
In the simplest definition, a meter bridge is simple type of potentiometer which may be used in school science laboratories to demonstrate the principle of resistance measurement by potentiometric means (Jan, 2013).
To construct a meter bridge involved the selection of various components and the connection of these parts into the workable system. These components like galvanometer, connecting wire, meter bridge rule, jockey, cell, key are discussed in next subsequent chapters.
This material is thus divided into five chapters beginning with chapter one which introduces the concept of work and ends in chapter five which contains conclusion, recommendation and the references.