A measuring instrument is a device for measuring a physical quantity. Units of measurement and their standards, which is concerned with the establishment, reproduction, conservation and transfer of units of measurement and their standards. All the basic concepts of mechanical engineering which will be useful to you in the case. The magnitude of one of the quantity is unknown, and it is compared with the predefined value. To the user of measuring instruments a knowledge of their construction. The basic principle of linear measurement mechanical type is that of comparison with standard dimensions on a suitably engraved instrument or device.
With our proven training solutions we have serviced corporations in the energy industry, process industries. The instruments used to measure any quantity are known as measuring instruments. While the basic objective of a measurement is to provide the required accuracy at. The main scale and the vernier scale that can slide. The standard as now defined can be reproduced to an accuracy of about 1 part in 109. It is basic that the measuring process inevitably alters the characteristics of both the source of the measured quantity and the measuring system itself, from which. Methods of measurement based on agreed units and standards. These encoders are widely used in a variety of measuring instruments as the length measuring. The two categories are nonprecision instruments and precision instruments. Getting ready one step at a time familiarity may not always breed contempt, but in precision gaging, it can certainly. Newly developed and updated electronic devices are based on state of the art technology. There are four basic types of temperature measuring devices, each of which uses a different principle.
Types of precision measuring instruments used in industry. Both signal generation signal generators, power supplies and signal measurement multimeters, scopes instruments are nonideal. The branch of engineering dealing with the design, construction. It might tell us how heavy an object is, or how hot, or how long it is. Tools and precision measurement test basic tools types applications precision measuring tools standard scaled. The methods of measuring mechanical quantities are discussed subsequently, overing both the basic and derived quantities. We deliver best in class training content for the entire workforce within operations and maintenance. Multiple choice questions and answers on measurement and instrumentation. Rulers, stopwatches, weighing scales, and thermometers are all measuring instruments.
With a need to make quality products which meet design specified tolerances, a large number of firms, research and development centers, and school and college laboratories use measuring instruments that have high accuracy and precision. These instruments are known as the ohmmeter, ammeter, voltmeter, frequency meter, flux meter, power factor meter, etc. The instrumentation and control systems notes pdf ics notes pdf book starts with the topics covering basic principles of measurement, units classification different principles used, ionization pressure gauges, cryogenic fuel level indicators bubler level indicators, measurement of acceleration and vibration, turbine flow meter. Measurement and control basics, 3rd edition thomas a.
Classification of measuring instruments the instrument used for measuring the physical and electrical quantities is known as the measuring instrument. In the physical sciences, quality assurance, and engineering, measurement is the activity of obtaining and comparing physical quantities of realworld objects and events. The disadvantage is they are unable to respond rapidly to measurement of dynamic and transient conditions. It is basic instrument of measurement, consist of two types of scale. It is an independent domain of knowledge dealing with the measurement of various physical quantities such as. During the act of measurement the measuring instrument takes energy from the signal source or measured medium and thus the signal source is altered. Instrumentation and control systems pdf notes ics pdf. The science of mechanical measurements has its roots in physics. To determine the measuring instrument capabilities and ensure that these are adequate for their respective measurements. In this page you can learn various important measuring instruments multiple choice questions answers,mcq on electrical measuring instruments with answers,mcq on instrumentation and measurement,sloved electrical measuring instruments objective questions answers, instrumentation multiple choice questions answers etc. Linear measuring instruments are categorized depending upon their accuracy.
Below, we have compiled a list of mechanical measuring instruments and. They are very reliable for static and stable conditions. Some of the recent developments such as laserdoppler techniques, holography, have also been included. The inclusion of an electrical measurement course in the undergraduate curriculum of electrical engineering is important in forming the technical and scientific knowledge of future electrical engineers.
Taper measuring instruments are used for the measuring slope type of surfaces on the components. Principles and methods of temperature measurement course content temperature can be measured via a diverse array of sensors. To accurately model our systems, we must take nonidealities into account. Instrumentation and measurement in electrical engineering. Important measuring instruments multiple choice questions. Basics of mechanical engineering pdf concepts useful for interviews by mohammed shafi june 2, 2019 april 5, 2020 basics of mechanical engineering pdf. Fundamentals of instrumentation and measurement edited by dominique placko. Multiple choice questions and answers on measurement and. The measurement units live not on a scale, but offsite in a calibration lab.
Many techniques have been developed for the measurement of pressure and vacuum. Skills and knowledge assessment test section v skat. Classification of measuring instruments electrical. Established standard objects and events are used as units, and the process of measurement gives a number relating the item under study and the referenced unit of measurement. Measurement in mechanical ngineering 6 the action of measuring something where measuring ascertains the size, amount or degree of something by using an instrument or device.
The meter and yard were redefined in terms of wave length of orange kr86 radiation as, 1 meter 1650763. Measuring instruments measuring instruments are used to measure physical quantities. Below are some examples of how the instruments themselves change our measurements. Skills and knowledge assessment test section v skat mechanic machinist four tests will be administered. In electrical, the instruments used to measure the resistance or current, voltage, frequency, flux, power factor, etc. The term measurement means the comparison between the two quantities of the same unit. Introduction to mechanical measurements and metrology.
This book explains the basic measurement techniques, instruments, and methods used in everyday practice. If the instruments can measure the basic electrical quantities, such as voltage and current are known as basic measuring instruments. Measurements are always made using an instrument of some kind. Mechanical equipment training \ precision measuring instruments training. Measurement and instruments objective questions and answers pdf free download. The least count of a measuring instrument is the smallest change in the measured quantity that can be resolved on the instrument s scale. Scientists, engineers and other humans use a vast range of instruments to perform their measurements.
Classification of measuring instruments circuit globe. All of them infer temperature by sensing some change in a physical characteristic. Electrical methods of indicating the output of detectors are more rapid than. Over the last 15 or 20 years a whole new technology of. Care is needed when taking a reading from a mechanical micrometer. Basic mechanical engineering interview questions answers pdf free download mcqs objective type questions lab viva online quiz test bits seminar topics. In the field of magnetic measurements the mechanical equipment is mainly used for the. Instruments used to measure pressure are called pressure gauges or vacuum gauges.
In addition linear units such as 1 in 30 or millimeters per meter are often used for specifying tapers and departures from squareness or parallelism. Unit 5 linear measuring devices and linear measuring. Measurements of surface roughness, using tally surfmechanical comparator. This need was largely sa tisfied, for the slow and robust machines of yesteryear, by the experienced ear and touch of the plant engineer, or by simple optical instruments measuring vibratory dis placement. It is basic that the measuring process inevitably alters the characteristics of both the source of the measured quantity and the measuring system itself, from which it must follow that there will always be some difference between the measured indication and the corresponding tobemeasured.
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