Different types of bridge circuits and its functions. This bridge is a modification of the wheatstone bridge circuit, used to measure resistance in the range. Removing l 1 from its position and when inserted l 2 in the same place then the balance conditions are the same except another set of values of the electrical components i. Perform engineering measurements andor unit mem12001b use comparison and basic measuring devices should be considered. Volume 1 of 4 module 1 basic electrical theory this module describes basic electrical concepts and introduces electrical terminology. Measurement of nonelectrical quantities authorstream. Tied arch bridges tied arch bridges have an a rchshaped superstructure, but differ from conventional arch bridges. Schering bridge theorythis bridge is used to measure to the capacitance of the capacitor, dissipation factor and measurement of relative permittivity. Also, time involved in the measurement is shortest. Principles and methods of temperature measurement course content temperature can be measured via a diverse array of sensors. Voltage, u, is the difference in electrical potential. Electrical field strength, e, is the negative of the gradient in electrical potential, i. All of them infer temperature by sensing some change in a physical characteristic. Arch bridges arches the banks carry the load and keep the ends of the bridge from spreading out arch bridges over under arch bridges oooovery strong if well designed oooocan be very beautiful tend to be very heavy need very strong abutments truss bridges truss bridges are mostly empty space, but very effective.
The obstacle to be crossed may be a river, a road, railway or a valley. In general, bridge forms a loop with a set of four arms or branches. Ac bridge circuits ac metering circuits electronics. G for semiconductor materials 5070 x that of metals. R, l, c voltage division experimental plots time domain frequency domain bode plots instrumentation. Some directreading conductivity meters have automatic temperature compensation built into the meter. A sensor is assumed to be linear so that its response y to a stimulus x is idealised to have the form. Standard specifications for bridge construction section 1, excavation march 20 1 1 1. The choke for which r 1 and l 1 have to measure connected between the points a and b. The bridge was originally developed for laboratory measurement purposes and one of the intermediate bridging points is often adjustable when so used. Transducers and sensors cp imperial college, autumn 2008 12 the following discussion refers to an implicit linear model for the sensor. Kubernetes for beginners docker introduction in 15. Signals which vary continuously with the change in the measurand are analog signals and the devices producing them are analog instruments.
The coverage of instrumentation portion is about 500 pages out of a total of nearly 1200 pages. No equipment range type quantity 1 schering bridge 2 cro ac 2 3 connecting wires 4 digital voltmeter 5 probes theory. The alternatives for bridge circuits anderson loop 112 3. Investigations of the effect of leakage currents made with a circuit shown in fig.
The required passage may be for a road, a railway, pedestrians, a canal or a pipeline. Classification of bridges instrumentation and control. Different ways to support bridges, beams, pillars, stands, arches, cables. Study of the operation of moving coil type, moving iron type and dynamometer type instruments apparatus required.
Strain gages structure of strain gages there are many types of strain gages. These measurements have been shown to be reliable across a variety of measurement voltages and procedures. Chapter 5 is about the compensation measurement methods, such as bridges and compensators. Electrical measurements full notes book pdf hae, i am unable to download the electrical measurements full notes book pdf. They consist of vertical piers and horizontal beams. Electronic measuring instruments bridges tutorialspoint. These bridges are operated on the principle of a dc bridge called a wheatstone bridge. Measurement of some electrical components by using a single a. The andersons bridge gives the accurate measurement of selfinductance of the circuit. The bridge circuit was mainly designed for measurement purpose in the laboratory. Bridge completion unless you are using a full bridge strain gauge sensor with four active gauges, you will. Materials material gage factor, g tcr 105 ni80 cr20 2. The national bridge inspection standards, or nbis, is the result of this legislation.
Introducing civil engineering measurements through bridges. Basic electrical measurements e80 feb 26, 2012 prof. It is notable that these measurements become unreliable at measurement voltages exceeding 65. Example 4 in the capacitance bridge shown above, resistor q is variable from 500 ohms to 10 kohms, and s ranges from 1 kohm to 3 kohms. Unit ii electrical and electronics instruments principle and types of analog and digital instruments voltmeters ammeters multimeters single and three phase wattmeters and energy meters magnetic measurements determination of bh curve and measurements of iron loss instrument transformers instruments for. Study model of different types of bridges technology supplies. Introducing civil engineering measurements through bridges kauser jahan, ralph a. Multiple choice questions and answers on measurement and. Errors in measuring high resistances on dc bridges springerlink. In circumstances where the application of this unit or. C bridges are used to measure the resistance while the a.
These instruments measure the unknown quantity by comparison with a standard. Alternating current bridge methods are of outstanding importance for measurement of electrical quantities, measurement of inductance, capacitance, storage factor, loss factor, etc. Kelvin double bridge or thomson bridge or fourwire ohm circuit. Lecturenotes on the theory of electrical measurements. Chapter 1 part 1 ac bridges notes, electrical measurement, electrical engineering. Accuracy, precision, resolution, reliability, repeatability, validity, errors and their analysis, standards of measurement. Example an ac bridge is in balance with the following constants. There are four basic types of temperature measuring devices, each of which uses a different principle. Bridge circuits now find many applications, both linear and nonlinear, including in instrumentation, filtering. The primary benefit of the circuit is its ability to provide extremely accurate measurements in contrast with something like a simple voltage divider. Modern cablestayed bridges have used both steel and con crete towers, including single and doubleplane vertical, ashaped, and doubleplane sloping towers. Let us consider the circuit of schering bridge as shown below. Aug 30, 2018 electrical measurements unit wise lecture notes and study materials in pdf format for engineering students.
Electrical field, e, is the negative of the gradient in electrical potential, i. Instead of trans ferring the weight of the bridge and traffic loads into thrust. Alternatives in the design and construction of cablestayed. Like other types of ac bridge circuits, the wien bridge circuit is also used for measurement purposes but is also commonly used for notch filters and oscillators. The electronic measurements and instrumentation notes pdf emi pdf notes book starts with the topics covering performance characteristics, ramp type, staircase ramp, wheat stone bridge, block schematic of cro, dual trace, strain gauges, flow measurement, flow measurement, etc. Roughly half of all bridges roughly half of all bridges in the united states are beam bridges.
Sta yed bridges the variety of cablestayed bridges illustrates the ingenious attempts to provide owners with unique design solutions. These bridges are composed of capacitors, inductors, and resistors in a wide variety of combinations. Different configurations of bridges by material used, lattice girder, box girder, etc. Capacitance, inductance, and resistance bridges you can measure capacitance, inductance, and resistance for precise accuracy by using ac bridges. Bridges used for strain measurements beside the whetstone bridge, there are some other electric circuits, the measuring bridges, with the ability to detect very low resistance. Therefore, proper selection and use of the bridge, signal conditioning, wiring, and data acquisition components are required for reliable measurements. A bridge circuit is one kind of electrical circuit wherein the two branches of the circuit are linked to a third branch which is connected in between the first two branches at some middle point along them. The frequencysensitive types may be used as frequency measurement devices if all component values are accurately known. Strain gauges and wheatstone bridges basic instrumentation and new applications for electrical measurement of nonelectrical quantities conference paper pdf available march 2011 with. The bridge is the advanced form of maxwells inductance capacitance bridge.
Beam bridges are the oldest known bridges and tend to be the simplest to design and build. The instruments used to measure any quantity are known as measuring instruments. May 04, 2020 chapter 1 part 1 ac bridges notes, electrical measurement, electrical engineering edurev notes is made by best teachers of electrical engineering ee. Bridge types trestle short spans supported by frames commonly used by railroad in 19th and early 20th centuries constructed of wrought iron, steel, or timber.
Demonstrate the proper use of a digital multimeter, an oscilloscope, a signal generator, and a computerbased data acquisition system daq in performing basic electrical measurements. Different types of bridge circuits and circuit diagrams a bridge circuit is one kind of electrical circuit wherein the two branches of the circuit are linked to a third branch which is connected in between the first two branches at some middle point along them. If the electrical components are arranged in the form a bridge or ring structure, then that electrical circuit is called a bridge. Electrical measurements measurement computing corp. We can classify the basic measuring instruments into the following two types. Cooper, modern electronic instrumentation and measurement techniques prentice hall, 1994. Measuring instruments classification deflecting, control and damping torques ammeters and voltmeters pmmc, moving iron type instruments expression for the deflecting torque and control torque errors and compensations, extension of range using shunts and series resistance. Chapter 4 describes the analogue measuring instruments, and how to use different types to measure various ac and dc voltages and currents. The inclusion of an electrical measurement course in the undergraduate curriculum of electrical engi neering is important in forming the technical and scientific knowledge of future electrical engineers. This book explains the basic measurement techniques, instruments, and methods used in everyday practice. Hay bridge is suitable for measuring following type of.
Errors, uncertainty, and reliability of signal processing 26 2. Companion resource for national bridge inspection standards. Strain gauge measurement involves sensing extremely small changes in resistance. Prepared for the thirdyear classes of the cooper union nightschool of science by anthony, william a.
The ac bridges is a natural outgrowth of the dc bridge wheatstone bridge in its basic form consists of four bridge arms a source of excitation and a null or balanced detector. There 1s an extensive coverage 4f electrical and electronic instrumentation in this edition of the book as compared with the earlier ones. Electrical measurements and their industrial applications. Dc bridges wheatstone bridge, ac bridges kelvin, hay, maxwell. Specific conductance, electrometric, wheatstone bridge. Electronic measurements and instrumentation pdf notes. For measurements on high voltage capacitors, the suitable bridge is. Electrical measurements in this module we will learn the most important principles of making electrical measurements in general, i. C bridges are used to measure the impedances consisting capacitance and inductances. A bridge circuit is mainly used to measure resistance.
The electrical science handbook consists of fifteen modules that are contained in four volumes. Schmalzel rowan university abstract freshman engineering students at rowan university are introduced to engineering measurements through a series of handson laboratories emphasizing teamwork, computer utilization, oral and. Bakshi measurements and measurement systems units and standards of measurements errors in measurements and their analysis measuring system fundamentals analog ammeters and voltmeters extension of instrument range analog measurement. In this method the unknown inductance is measured by comparing it with the standard inductance. Instrumentation and measurement in electrical engineering. Electrical measurement ee electrical and electronics measurement, important gate questions. The deflection type dynamometer type wattmeter is a. In anderson bridge, the unknown inductance is compared with the standard fixed capacitance which is connected between the two arms of the bridge. They are used when a higher accuracy of measurements is desired. This document is highly rated by electrical engineering ee students and has been viewed 753 times. Cooper, modern electronic instrumentation and measurement techniques prentice hall. Conclusions glossary bibliography summary electrical resistance strain gages are sensors fabricated from thin foil or wire type conductors that. Ac bridge circuits often have more than one adjustment, since both impedance magnitude and phase angle must be properly matched to balance.
The following is a brief description of the information presented in each module of the handbook. The nbis requires inspection of all publicly owned highway bridges greater than 20 feet in length. Some impedance bridge circuits are frequencysensitive while others are not. Alternatively, a thermistor device as described by hughes 1966 provides a convenient means of. Sarah harriss lecture from 2009 overview circuits electrical building blocks. Electrical measuring instruments electrical measuring instruments published by iskra mis, d.
Electrostatic voltmeters electrometer type and attracted disc type extension of range of e. R, l, c voltage division experimental plots time domain frequency domain bode plots. Ac bridges for measurement of c 1 desauty bridge 2 weins bridge series 3 schering bridge ac bridges for measurement of l 4 anderson bridge 5 maxwell inductance bridge. Classification, absolute and secondary instruments, indicating instruments, control, balancing and damping, constructional details, characteristics, errors in measurement, ammeters, voltmeters. We can classify the bridge circuits or bridges into the following two categories based on the voltage signal with which those can be operated. If the instruments can measure the basic electrical quantities, such as voltage and current are known as basic measuring instruments. Using t hese conditions one by one electrical components are measured by fixing other components. Dc bridges bridge can be a very useful component voltage dividers connected nulldetector meter movement connected between f the other three, which are calibrated, or whose 1r 4 r 3r 2 with the null detector, and. Hence such quantities are required to be sensed and changed into some other form of quantities. C bridges use the alternating voltage as the excitation voltage. Maxwell wein bridge configuration for measurement of inductance and wein bridge for measurement of capacitance. A wheatstone bridge is an electrical circuit used to measure an unknown electrical resistance by balancing two legs of a bridge circuit, one leg of which includes the unknown component. Each branch may contain one or two electrical components.
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