Instructor: Dr Alina Mirza Text Books Fundamentals of Instrumentation by U. A. Bakshi, A. V Bakshi & K. A. Bakshi Introduction to Instrumentation, Sensors & Process Control by William C. Dunn Measurement and Instrumentation Principles, by Alan S. Morris Reference Book Instrumentation, Measurement and Analysis by Nakra, Chaudhary Principles of Electronic Instrumentation and Measurement by Berlin & Getz. Dr Alina Mirza, Dept of EE MCS, NUST Credit Hours : 2+1 Tentative GRADING POLICY: OHT I + OHT II Final Exam Quiz Assignments / Project Dr Alina Mirza, Dept of EE MCS, NUST : : : : 30% 50% 10% 10% Project/ assignment will be given in groups of three. List of Groups to be provided by class senior WITHIN this week. Groups once formed will and cannot be changed till the end of semester. Plagiarism/copying will result in ZERO credit of either end. 20% deduction for any assignment submitted after the due date. Missed quizzes will NOT be taken on a latter date, you will be awarded zero credit for an on purpose missed quiz. You may be awarded average marks /re-quized once only, based on the following exceptions: Exceptions for missing the quiz: ▪ Intimate me prior to the quiz if you need to be somewhere/ or will not be able to attend the quiz. ▪ You must have a valid reason for missing the quiz e.g. death of a nearby relative or on duty if intimidated by the dept. Dr Alina Mirza, Dept of EE MCS, NUST Attendance will only be marked if you are present in the class. Absence from the class whether due to any emergency or due to official duty will still be marked as absent. Neither the class senior nor any one else may ask the instructor to mark an absent student as present. 25% leverage on attendance is given to all students which may be utilized for all problems that the students face. Dr Alina Mirza, Dept of EE MCS, NUST Contact ▪ Office hours ▪ Contact: 10:00 am-12:00pm Every Thur alinamirza@mcs.edu.pk Lectures, announcements, and other related material will be intimated through LMS or email to the class senior. Cell phone: only given to class senior for class correspondence , the instructor is not obliged to cater for any personal issues. Attendance / Marks cases to be discussed only in the office, well before time. Last week cases will not be considered. Dr Alina Mirza, Dept of EE MCS, NUST 1 Measurement Basics and Standards Introduction, Advantages of Measurement, Units, Standards, Dimensions, Unit conversions, Prefixes, Physical Constants, Significant Figures, Examples, Common Electrical Units with derivations 2 Instrumentation Basics, Classification and Characteristics Classification of Instruments, Functional Elements of an Instrumentation System, Performance Characteristics (Calibration), Static Characteristics (Accuracy, Precision …), Dynamic Characteristics (Response, Lag,…) 3 Errors in Measurement System and Types of Errors, Methods of Measurement, Loading effect Loading effect 4 Basic DC Electrical Instruments and their Measurements Measurement of Basic Physical Quantities(Current, Voltage, Power) Basic DC Ammeter , Multi range Ammeter , Basic DC voltmeter , Multi range Voltmeter, DC Resistance, Meter Calibration , Basic Dynamometer ,Basic Wattmeter 5 Basic AC Electrical Instruments and their Measurements Half Wave Rectifiers, Full Wave Rectifiers, AC Voltmeters, Meter Correction 6 Other Quantities Measurement Capacitance Measurement Instrument, Inductance Measurement Instrument, Frequency and Phase Measurement Instrument 7 Bridge Circuits AC, DC, Resistance , Capacitance, Inductance etc 8 Oscilloscopes Types, CRO … 9 Measurement of Physical Temperature, Pressure, Flow, Motion, Level, Miscellaneous quantities Quantities and Sensor Instruments Dr Alina Mirza, Dept of EE MCS, NUST What is Measurement? “Measurement means to monitor a process or an operation and using an instrument, express the parameter, quantity or variable in terms of meaningful numbers.” “Measurement provides a means of expressing a natural phenomena or various processes in quantitative terms.” Measuring instrument is a “device for determining the value or magnitude of a quantity or variable.” Dr Alina Mirza, Dept of EE MCS, NUST 1. 2. 3. Most of quantities can be converted by transducers into the electrical or electronic signals. An electrical signal can be amplified, filtered, multiplexed, sampled and measured. The measurement obtained can be converted into digital form for automatic analysis and recording. Dr Alina Mirza, Dept of EE MCS, NUST For any measurement, a well defined set of standards and units is essential A small number of physical quantities selected arbitrarily are called fundamental quantities. All other physical quantities are then defined as derived quantities. A unit is a defined sample of a quantity. Dr Alina Mirza, Dept of EE MCS, NUST In the physical world there are only six fundamental quantities: The branch of physics known as mechanics gives us the fundamental quantities of length, mass, and time. Thermodynamics adds the fundamental quantity of temperature difference. Electricity and Magnetism give us the quantity of electric current. Optics give us the quantity of light intensity Chemistry gives us the quantity of amount of substance . Dr Alina Mirza, Dept of EE MCS, NUST SI Units or System International Units – Based on a defined standard Dr Alina Mirza, Dept of EE MCS, NUST Dr Alina Mirza, Dept of EE MCS, NUST Commonly Encountered Electrical Units Functional Elements of an Instrument Instrument Classification Performance Characteristics Static Characteristics Dynamic Characteristics Methods of Measurement Types of Errors Loading Effects Dr Alina Mirza - Dept of EE MCS, NUST 15 COMMONLY ENCOUNTERED ELECTRICAL UNITS Dr Alina Mirza - Dept of EE MCS, NUST 16 VOLT • The volt, named for Alessandro Conte Volta, is the SI unit of potential difference • Potential Difference is the force that causes charges to move through an electric circuit. • On the basis of moving charges, a difference of one volt exists between two points in a circuit if one joule of energy is required to move a 1-coulomb charge from the point of lower potential to the point to higher potential • From this definition, voltage then has the dimensions of joules per coulomb Dr Alina Mirza - Dept of EE MCS, NUST 17 AMPERE • The ampere, named for Andre Marie Ampere, • Is the SI unit of electric current • It is a measure of the rate at which electrical charge passes a given point in a Circuit • A current of one ampere will cause a charge of one coulomb to pass a given point in a circuit in one second • The quantity symbol for current is represented by the letter I , after the French word for current, intensité • we adhere strictly to conventional current flow Dr Alina Mirza - Dept of EE MCS, NUST 1 8 OHM • The ohm, named for George Simon Ohm • Is the SI unit of electrical resistance • It is a measure of the opposition to a steady current flow due to the molecular properties of the conductor • By definition, the voltage across the element divided by the current flowing through the element • Resistance is considered as proportionality constant that linearly relates the potential difference between two points in a circuit and the current that results from the potential difference between them (Ohm's law) • The quantity symbol for resistance is indicated by the letter R • The unit symbol for ohm marked byMCS, theNUST uppercase Greek letter omega (Ω) Dr Alinais Mirza - Dept of EE 19 FARAD • The farad, named for Michael Faraday • Is the SI unit of capacitance • Capacitance is a measure of the charge that is stored on a capacitor as a function of the applied voltage • Is equal to the stored charge divided by the voltage across the capacitor • The quantity symbol for capacitance is indicated by the letter C (and should not be confused with the unit symbol for coulombs, represented by the letter C) • The unit symbol for farads is represented by the letter F • The farad is an extremely large unit, capacitance units are most commonly expressed in terms ofDreither microfarads (μF) or picofarads (pF) Alina Mirza - Dept of EE MCS, NUST 20 HENRY • The henry, named for Joseph Henry • Is the SI unit of inductance • It is a proportionality factor that relates induced voltage in a coil of wire to the rate of change of current with time • The quantity symbol for inductance is indicated by the letter L (in italic) • The unit symbol for henry is represented by the letter H Dr Alina Mirza - Dept of EE MCS, NUST 21 HERTZ • The hertz , named for Heinrich Rudolph Hertz, is the SI unit of frequency • A frequency of one hertz is defined as one cycle of the waveform per one second • The quantity symbol for frequency is generally indicated by the letter f, • The unit symbol for hertz is Hz Dr Alina Mirza - Dept of EE MCS, NUST 22 Functional Elements of an Instrument Dr Alina Mirza - Dept of EE MCS, NUST 23 Functional elements of an instruments are divide into three parts The physical, ▪ Primary sensing element ▪ Data conditioning element ▪ Data presentation element Dr Alina Mirza - Dept of EE MCS, NUST chemical, electrical quantity, property, process, variable or condition to be measured is referred to as measurand 24 An element of an instrument which makes, first, the contact with quantity to be measured is called primary sensing element The first detection of measurand is done by PSE Generally transducers follows PSE, which converts measurand into corresponding electrical signals. Dr Alina Mirza - Dept of EE MCS, NUST 25 When output from PSE is not suitable for actual measurement system, variable conversion element is required e.g. Analog to Digital convertors The original information about measurand should be retained as it is while performing conversion Some instruments need variable conversion element and some do not Dr Alina Mirza - Dept of EE MCS, NUST 26 If the output is not enough to drive the next stage, manipulation is required. Manipulation involves change in the numerical value of the signal. Attenuators / Amplifiers. Signal conditioning, to obtain signal in pure form from highly distorted form .eg. Clipping ,clamping, modulation. Variable conversion + variable manipulation + signal conditioning = Data Conditioning or Signal Conditioning element Dr Alina Mirza - Dept of EE MCS, NUST 27 When elements of system are physically separated, it is necessary to transmit the data from one stage to other. This is done through data transmission element Signal conditioning + Data transmission = Intermediate stage of an instrument Dr Alina Mirza - Dept of EE MCS, NUST 28 Transmitted data may be used by the system for monitoring, controlling or analysis purpose The observer should get to data in proper form. This is done by data presentation element ▪ Monitoring: visual display devices ▪ Record & Analysis: magnetic tapes, recorders, high speed cameras ▪ Control & Analysis: microprocessors, computers, microcontrollers This stage is known as terminating stage Dr Alina Mirza - Dept of EE MCS, NUST 29 1. 2. 3. 4. How many kilo meters are there in 2.5 miles? If 1 mile = 5280 ft and 1 ft =0.305 m. How many centi meters are there 56.43 ft? if 1 ft = 0.305 m What is the weight of 3.7 𝑙𝑏 mass in Newton? if 1 lb-weight = 4.448N A 110 V electric motor uses 5.8 A. If the motor is 87% efficient, then how many horsepower the motor will generate? If 1 hp = 746Watt Dr Alina Mirza, Dept of EE MCS, NUST