Introduction of Measurement

INTRODUCTION OF MEASUREMENT

Electrical energy is being used in the manufacture of many commodities. In order to ensure quality and efficiency, it is important that we should be able to measure accurately the electrical quantities involved. The instruments used to measure electrical quantities (e.g. current, voltage, power, energy etc.) are called electrical instruments. These instruments are generally named after the electrical quantity to be measured. Thus the instruments which measure current, voltage, power and energy are called ammeter, voltmeter, and wattmeter and energy meter respectively.

The accuracy, convenience and reliability of electrical instruments are mainly responsible for the widespread use of electrical methods of measurements.

Basic requirements for a meaningful measurement

The standard used for comparison purposes must be accurately defined and should be commonly accepted. The apparatus used and the method adopted must be provable (verifiable).

Significance of Measurement

Importance of Measurement is simply and eloquently expressed in the following statement of famous physicist Lord Kelvin: "often say that when you can measure what you are speaking about and can express it in numbers, you know something about it; when you cannot express in it numbers your knowledge is of meager and unsatisfactory kind"