The Accuracy Comparison of Oscilloscope and Voltmeter Utilizated in Getting Dielectric Constant Values
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1806-A Electronic Voltmeter, Manual
OPERATING INSTRUCTIONS TYPE 1806-A ELECTRONIC VOLTMETER Form 1806-0100-C March, 1967 Copyright 1963 General Radio Company West Concord, Massachusetts, USA GENERAL RADIO COMPANY WEST CONCORD, MASSACHUSETTS, USA SPECIFICATIONS DC VO~TMETER Voltage Ro.nge: Four ranges, 1.5, 15, 150, and 1500 V, full scale, positive or negative. Minimum reading is 0.005 V. Input Resistance: 100 M!'l, ±5%; also "open grid" on all but the 1500-V range. Grid current is less than I0-10 A. Accuracy: ±2% of indicated value from one-tenth of full scale to full scale; ±0.2% of full scale from one-tenth of full scale to zero. Scale is logarithmic from one-tenth of full scale to full scale, permitting constant-percentage readability over that range. AC VOLTMETER Voltage Range: Four ranges, 1.5, 15, 150, and 1500 V, full scale. Minimum reading on most sensitive range is 0.1 V. Input Impedance: Probe, approximately 25 Mn in parallel with 2 pF; with TYPE 1806-P2 Range Multiplier, 2500 M!'l in parallel with 2 pF; at binding post on panel, 25 Mn in parallel with 30 pF. Accuracy: At 400 c/ s, ±2% of indicated value from 1.5 V to 1500 V; ±3% of indicated value from 0.1 V to 1.5 V. Waveform Error: On the higher ac-voltage ranges, the instrument operates as a peak voltmeter, calibrated to read rms values of a sine wave or 0.707 of the peak value of a complex wave. On distorted waveforms the percentage deviation of the reading from the rms value may be as large as the percentage of harmonics present. -
Equivalent Resistance
Equivalent Resistance Consider a circuit connected to a current source and a voltmeter as shown in Figure 1. The input to this circuit is the current of the current source and the output is the voltage measured by the voltmeter. Figure 1 Measuring the equivalent resistance of Circuit R. When “Circuit R” consists entirely of resistors, the output of this circuit is proportional to the input. Let’s denote the constant of proportionality as Req. Then VRIoeq= i (1) This is the same equation that we would get by applying Ohm’s law in Figure 2. Figure 2 Interpreting the equivalent circuit. Apparently Circuit R in Figure 1 acts like the single resistor Req in Figure 2. (This observation explains our choice of Req as the name of the constant of proportionality in Equation 1.) The constant Req is called “the equivalent resistance of circuit R as seen looking into the terminals a- b”. This is frequently shortened to “the equivalent resistance of Circuit R” or “the resistance seen looking into a-b”. In some contexts, Req is called the input resistance, the output resistance or the Thevenin resistance (more on this later). Figure 3a illustrates a notation that is sometimes used to indicate Req. This notion indicates that Circuit R is equivalent to a single resistor as shown in Figure 3b. Figure 3 (a) A notion indicating the equivalent resistance and (b) the interpretation of that notation. Figure 1 shows how to calculate or measure the equivalent resistance. We apply a current input, Ii, measure the resulting voltage Vo, and calculate Vo Req = (1) Ii The equivalent resistance can also be measured using and ohmmeter as shown in Figure 4. -
Part 2 - Condenser Testers and Testing Correctly Part1 Condenser Testers and Testing Correctly.Doc Rev
Part 2 - Condenser Testers and Testing Correctly Part1_Condenser_Testers_And_Testing_Correctly.doc Rev. 2.0 W. Mohat 16/04/2020 By: Bill Mohat / AOMCI Western Reserve Chapter If you have read Part 1 of this Technical Series on Condensers, you will know that the overwhelming majority of your condenser failures are due to breakdown of the insulating plastic film insulating layers inside the condenser. This allows the high voltages created by the “arcing” across your breaker points to jump through holes in the insulating film, causing your ignition system to short out. These failures, unfortunately, only happen at high voltages (often 200 to 500Volts AC)….which means that the majority of “capacitor testers" and "capacitor test techniques" will NOT find this failure mode, which is the MAJORITY of the condenser failure you are likely to encounter. Bottom line is, to test a condenser COMPLETELY, you must test it in three stages: 1) Check with a ohmmeter, or a capacitance meter, to see if the condenser is shorted or not. 2) Assuming your condenser is not shorted, use a capacitance meter to make sure it has the expected VALUE of capacitance that your motor needs. 3) Assuming you pass these first two step2, you then need to test your condenser on piece of test equipment that SPECIFICALLY tests for insulation breakdown under high voltages. (As mentioned earlier, you ohmmeter and capacitance meter only put about one volt across a capacitor when testing it. You need to put perhaps 300 or 400 times that amount of voltage across the condenser, to see if it’s insulation has failed, allowing electricity to “arc across" between the metal plates when under high voltage stress. -
Voltage and Power Measurements Fundamentals, Definitions, Products 60 Years of Competence in Voltage and Power Measurements
Voltage and Power Measurements Fundamentals, Definitions, Products 60 Years of Competence in Voltage and Power Measurements RF measurements go hand in hand with the name of Rohde & Schwarz. This company was one of the founders of this discipline in the thirties and has ever since been strongly influencing it. Voltmeters and power meters have been an integral part of the company‘s product line right from the very early days and are setting stand- ards worldwide to this day. Rohde & Schwarz produces voltmeters and power meters for all relevant fre- quency bands and power classes cov- ering a wide range of applications. This brochure presents the current line of products and explains associated fundamentals and definitions. WF 40802-2 Contents RF Voltage and Power Measurements using Rohde & Schwarz Instruments 3 RF Millivoltmeters 6 Terminating Power Meters 7 Power Sensors for URV/NRV Family 8 Voltage Sensors for URV/NRV Family 9 Directional Power Meters 10 RMS/Peak Voltmeters 11 Application: PEP Measurement 12 Peak Power Sensors for Digital Mobile Radio 13 Fundamentals of RF Power Measurement 14 Definitions of Voltage and Power Measurements 34 References 38 2 Voltage and Power Measurements RF Voltage and Power Measurements The main quality characteristics of a parison with another instrument is The frequency range extends from DC voltmeter or power meter are high hampered by the effect of mismatch. to 40 GHz. Several sensors with differ- measurement accuracy and short Rohde & Schwarz resorts to a series of ent frequency and power ratings are measurement time. Both can be measures to ensure that the user can required to cover the entire measure- achieved through utmost care in the fully rely on the voltmeters and power ment range. -
Lab 5 AC Concepts and Measurements II: Capacitors and RC Time-Constant
Sonoma State University Department of Engineering Science Fall 2017 EE110 Laboratory Introduction to Engineering & Laboratory Experience Lab 5 AC Concepts and Measurements II: Capacitors and RC Time-Constant Capacitors Capacitors are devices that can store electric charge similar to a battery (but with major differences). In its simplest form we can think of a capacitor to consist of two metallic plates separated by air or some other insulating material. The capacitance of a capacitor is referred to by C (in units of Farad, F) and indicates the ratio of electric charge Q accumulated on its plates to the voltage V across it (C = Q/V). The unit of electric charge is Coulomb. Therefore: 1 F = 1 Coulomb/1 Volt). Farad is a huge unit and the capacitance of capacitors is usually described in small fractions of a Farad. The capacitance itself is strictly a function of the geometry of the device and the type of insulating material that fills the gap between its plates. For a parallel plate capacitor, with the plate area of A and plate separation of d, C = (ε A)/d, where ε is the permittivity of the material in the gap. The formula is more complicated for cylindrical and other geometries. However, it is clear that the capacitance is large when the area of the plates are large and they are closely spaced. In order to create a large capacitance, we can increase the surface area of the plates by rolling them into cylindrical layers as shown in the diagram above. Note that if the space between plates is filled with air, then C = (ε0 A)/d, where ε0 is the permittivity of free space. -
Capacitance and Dissipation Factor Measurementst from 1 Khz to 10 Mhz " Presenter: A
Capacitance and Dissipation Factor Measurementst from 1 kHz to 10 MHz " Presenter: A. D. Koffman NIST, 220/B162, Gaithersburg, MD 20899 (301) 975-4518 Paper Authors A. D. Koffman, B. C. Waltrip, N. M. Oldham National Institute of Standards and TechnologY: Gaithersburg, MD S. Avramov-Zamurovic U.S. Naval Academy Annapolis, MD Abstract: A measurement technique developed by K. Yokoi et al. at Hewlett-Packard Japan, Ltd. has been duplicated and evaluated at the National Institute of Standards and Technology (NIST) to characterize four-tenninal pair capacitors. The technique is based on an accurate three-terminal measurement made at 1 kHz using a capacitance bridge and wideband single-port measurementsmadebetween30MHzand200 MHz usinga networkanalyzer. The measurement data are fitted to the four-tenninal pair admittance model defmed by R. Cutkosky to compute capacitance and dissipation factor at any frequency up to 10 MHz. Capacitors characterized using this technique will be used as impedance reference standards for a general- purpose digital impedance bridge recently developed at NIST to calibrate inductors and ac resistors. The technique could also lead to a future NIST Special Test for dissipation factor. INTRODUCTION Recent efforts by the Electricity Division at the National Institute of Standards and Technology (NIST) to develop improved impedance comparison methods from 20 Hz to 1 MHz (1)have made it necessary to fmd a means to evaluate the reference impedances used in such comparisons. The impedance-characterization method discussed in this paper is described by Suzuki, et al. (2)and is based on the four-tenninal pair impedance work of Cutkosky (3)and Jones (4,5) The four-terminal pair impedance, Z4tp'of a device is defined as a combination of its real component, R, and its imaginary component, X: Z41p= R+ jX. -
Massachusetts Institute of Technology Department of Electrical Engineering and Computer Science
Massachusetts Institute of Technology Department of Electrical Engineering and Computer Science 6.002 - Circuits and Electronics Fall 2004 Lab Equipment Handout (Handout F04-009) Prepared by Iahn Cajigas González (EECS '02) Updated by Ben Walker (EECS ’03) in September, 2003 This handout is intended to provide a brief technical overview of the lab instruments which we will be using in 6.002: the oscilloscope, multimeter, function generator, and the protoboard. It incorporates much of the material found in the individual instrument manuals, while including some background information as to how each of the instruments work. The goal of this handout is to serve as a reference of common lab procedures and terminology, while trying to build technical intuition about each instrument's functionality and familiarizing students with their use. Students with previous lab experience might find it helpful to simply skim over the handout and focus only on unfamiliar sections and terminology. THE OSCILLOSCOPE The oscilloscope is an electronic instrument based on the cathode ray tube (CRT) – not unlike the picture tube of a television set – which is capable of generating a graph of an input signal versus a second variable. In most applications the vertical (Y) axis represents voltage and the horizontal (X) axis represents time (although other configurations are possible). Essentially, the oscilloscope consists of four main parts: an electron gun, a time-base generator (that serves as a clock), two sets of deflection plates used to steer the electron beam, and a phosphorescent screen which lights up when struck by electrons. The electron gun, deflection plates, and the phosphorescent screen are all enclosed by a glass envelope which has been sealed and evacuated. -
Electronic Voltmeters and Ammeters - Alessandro Ferrero, Halit Eren
ELECTRICAL ENGINEERING – Vol. II - Electronic Voltmeters and Ammeters - Alessandro Ferrero, Halit Eren ELECTRONIC VOLTMETERS AND AMMETERS Alessandro Ferrero Dipartimento di Elettrotecnica, Politecnico di Milano, Italy Halit Eren Curtin University of Technology, Perth, Western Australia Keywords: currents, voltages, measurements, standards, analog voltmeters, digital voltmeters, microvoltmeters, oscilloscopes Contents 1. Introduction. 2. Analog Meters 2.1. DC Analog Voltmeters and Ammeters 2.2. AC Analog Voltmeters and Ammeters 2.3. True rms Analog Voltmeters 3. Digital Meters 3.1. Dual-Slope DVMs 3.2. Successive-Approximation ADCs 3.3. AC Digital Voltmeters and Ammeters 3.4. Frequency Response of AC Meters 4. Radio-Frequency Microvoltmeters 5. Vacuum-Tube Voltmeters and Oscilloscopes 5.1. Analog Oscilloscopes 5.2. Digital Storage Oscilloscopes (DSOs) 5.3. Portable Oscilloscopes 5.4. High-Voltage Oscilloscopes Appendix Glossary Bibliography Biographical Sketches Summary Voltage UNESCOand current measurements are – esse EOLSSntial parts of engineering and science. Instruments that measure voltages and currents are called voltmeters and ammeters, respectively. ThereSAMPLE are two distinct types of voltmeterCHAPTERS and ammeter, which differ from each other by the operating principle that they are based on: electromechanical instruments and electronic instruments, which also include oscilloscopes. Electromechanical voltmeters and ammeters, including thermal-type instruments, represent early technology, but still are used in many applications. Basic elements of voltages and currents from the basic physical principles have been introduced in the electromechanical voltage and current measurements section. Also, voltage and currents standards have been dealt with in detail in other articles. ©Encyclopedia of Life Support Systems (EOLSS) ELECTRICAL ENGINEERING – Vol. II - Electronic Voltmeters and Ammeters - Alessandro Ferrero, Halit Eren In this article, modern electronic voltmeters and ammeters are discussed. -
EE 462G Laboratory #1 Measuring Capacitance
EE 462G Laboratory #1 Measuring Capacitance Drs. A.V. Radun and K.D. Donohue (1/24/07) Revised by Samaneh Esfandiarpour and Dr. David Chen (9/17/2019) Department of Electrical and Computer Engineering University of Kentucky Lexington, KY 40506 I. Instructional Objectives Introduce lab instrumentation with linear circuit elements Introduce lab report format Develop and analyze measurement procedures based on two theoretical models Introduce automated lab measurement and data analysis II. Background A circuit design requires a capacitor. The value of an available capacitor cannot be determined from its markings, so the value must be measured; however a capacitance meter is not available. The only available resources are different valued resistors, a variable frequency signal generator, a digital multi-meter (DMM), and an oscilloscope. Two possible ways of measuring the capacitor’s value are described in the following paragraphs. For this experiment, the student needs to select resistors and frequencies that are convenient and feasible for the required measurements and instrumentation. Be sure to use the digital multi-meter (DMM) to measure and record the actual resistance values used in each measurement procedure. III. Pre-Laboratory Exercise Step Response Model 1. For a series circuit consisting of a voltage source v(t), resistor R, and capacitor C, derive (show all steps) the complete solution for the capacitor voltage vc(t) when the source is a step with amplitude A and the initial capacitor voltage is 0. 2. Assume the source v(t) is a function generator, where the source voltage can only be measured after the 50 Ω internal resistance. -
Capacitance Meter MUDIT AGARWAL
Capacitance Meter MUDIT AGARWAL Nasiha Ali The principle of operating is counting the pulse oscillator during a fixed time interval produced by another lower frequency oscillator. This oscillator uses the capacitor being measured as the timing element. The capacitance measurement is proportional during pulse counting during a fixed time interval. The astable oscillator formed by IC1c K K K K K K K K K K K K K K K K K K K K K 1 1 1 1 1 1 1 9V 1 1 1 1 1 1 1 1 1 1 1 1 1 1 + + 9V produces a pulse train of constant frequency. Gate 13 12 11 10 9 15 14 3 3 13 12 11 10 9 15 14 13 12 11 10 9 15 14 3 IC4 IC5 IC6 4 4 8 8 4 IC1a also form oscillator whose oscillation period 4511 4511 8 4511 16 5 6 2 1 7 16 16 5 6 2 1 7 6 2 1 7 5 is given approximately by the equation: T=0.7RC. 1C1c Period T is linearly dependent on the capacitance 4093 9 6 5 4 3 2 14131211 10 8 6 5 4 3 16 2 IC2 IC3 10 1 1 C. This period is used as the time interval for one 4518 4518 8 9 7 15 7 15 9 1.5M measurement. The differentiator network following 2K C1 the oscillator creates the negative spikes shaped in 1C1a 9V + 220pf 4093 14 K 1 5 1 9 3 4 R K narrow pulses by IC1b NAND Schmitt trigger. -
LCR Meter PCE-UT 603
www.pce-industrial-needs.com Tursdale Technical Services Ltd Unit N12B Tursdale Business Park Co. Durham DH6 5PG United Kingdom Phone: +44 ( 0 ) 191 377 3398 Fax: +44 ( 0 ) 191 377 3357 [email protected] http://www.industrial-needs.com/ Manual LCR Meter PCE-UT 603 [email protected] Table of contents Overview .................................................................................................................................................. 3 Safety Information ................................................................................................................................... 3 Rules for Safe Operation .......................................................................................................................... 3 International Electrical Symbols .............................................................................................................. 4 The Meter Structure ................................................................................................................................. 4 Functional Buttons ................................................................................................................................... 5 Display Symbols ...................................................................................................................................... 5 Measurement Operation ........................................................................................................................... 6 A. Measuring -
The RC Circuit
The RC Circuit The RC Circuit Pre-lab questions 1. What is the meaning of the time constant, RC? 2. Show that RC has units of time. 3. Why isn’t the time constant defined to be the time it takes the capacitor to become fully charged or discharged? 4. Explain conceptually why the time constant is larger for increased resistance. 5. What does an oscilloscope measure? 6. Why can’t we use a multimeter to measure the voltage in the second half of this lab? 7. Draw and label a graph that shows the voltage across a capacitor that is charging and discharging (as in this experiment). 8. Set up a data table for part one. (V, t (0-300s in 20s intervals, 360, and 420s)) Introduction The goal in this lab is to observe the time-varying voltages in several simple circuits involving a capacitor and resistor. In the first part, you will use very simple tools to measure the voltage as a function of time: a multimeter and a stopwatch. Your lab write-up will deal primarily with data taken in this part. In the second part of the lab, you will use an oscilloscope, a much more sophisticated and powerful laboratory instrument, to observe time behavior of an RC circuit on a much faster timescale. Your observations in this part will be mostly qualitative, although you will be asked to make several rough measurements using the oscilloscope. Part 1. Capacitor Discharging Through a Resistor You will measure the voltage across a capacitor as a function of time as the capacitor discharges through a resistor.