Chapter 2 : Dc Meters
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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. -
The Accuracy Comparison of Oscilloscope and Voltmeter Utilizated in Getting Dielectric Constant Values
Proceeding The 1st IBSC: Towards The Extended Use Of Basic Science For Enhancing Health, Environment, Energy And Biotechnology 211 ISBN: 978-602-60569-5-5 The Accuracy Comparison of Oscilloscope and Voltmeter Utilizated in Getting Dielectric Constant Values Bowo Eko Cahyono1, Misto1, Rofiatun1 1 Physics Departement of MIPA Faculty, Jember University, Jember – Indonesia, e-mail: [email protected] Abstract— Parallel plate capacitor is widely used as a sensor for many purposes. Researches which have used parallel plate capacitor were investigation of dielectric properties of soil in various temperature [1], characterization if cement’s dielectric [2], and measuring the dielectric constant of material in various thickness [3]. In the investigation the changing of dielectric constant, indirect method can be applied to get the dielectric constant number by measuring the voltage of input and output of the utilized circuit [4]. Oscilloscope is able to measure the voltage value although the common tool for that measurement is voltmeter. This research aims to investigate the accuracy of voltage measurement by using oscilloscope and voltmeter which leads to the accuracy of values of dielectric constant. The experiment is carried out by an electric circuit consisting of ceramic capacitor and sensor of parallel plate capacitor, function generator as a current source, oscilloscope, and voltmeters. Sensor of parallel plate capacitor is filled up with cooking oil in various concentrations, and the output voltage of the circuit is measured by using oscilloscope and also voltmeter as well. The resulted voltage values are then applied to the equation to get dielectric constant values. Finally the plot is made for dielectric constant values along the changing of cooking oil concentration. -
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. -
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. -
Power Transformers and Reactors
GE Grid Solutions Power Transformers and Reactors Imagination at work Today’s Environment The Right Transformer Growth in the world's population and economy, will result in a for the Right Application substantial increase in energy demand over the coming years. GE offers utilities advanced solutions to improve grid stability and The International Energy Agency (IEA)1 estimates that $20 trillion increase efficiency of transmission infrastructure. will need to be invested in power and grid technologies, over the next 25 years, to keep up with demand. According to a 2015 IEA From low to ultra-high voltage; small to extra-large power report2, renewable energy will represent the largest single source ratings; standard to the most complex designs; GE has the of electricity growth over the next five years - rising to a 26 % right share of global generation. solution for every application. Integrating renewable energy sources into the grid can conflict Conventional Power Transformers with Utilities’ existing modernization and optimization plans. From 5 MVA up to 1500 MVA & 765 kV Utilities face increasing challenges of reliability, safety, power ' Small & medium power transformers quality and economics when planning substations and choosing ' Large power transformers switchgear. ' Generator step-up transformers Additionally, power systems are interconnected and highly ' Autotransformers complex networks which are susceptible to instabilities. Managing and maintaining today‘s complex grid pose many Oil-Immersed Reactors challenges, including: Up to 250 Mvar & 765 kV / 2640 Mvar ' Increasing grid efficiency and resilience without adequate ' Shunt reactors funding to invest in new capital equipment. ' Series reactors ' Expertise to manage the grid is rapidly diminishing due to the ' Earthing reactors lack of skilled, technical resources in the workplace. -
Performance Study on Commercial Magnetic Sensors Unmanned Aerial
IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT, VOL. 69, NO. 4, APRIL 2020 1397 Performance Study on Commercial Magnetic Sensors for Measuring Current of Unmanned Aerial Vehicles Ke Zhu , Xuyang Liu , Student Member, IEEE, and Philip W. T. Pong , Senior Member, IEEE Abstract— The industrial investment in unmanned aerial vehi- UAVs have found many applications, such as condition moni- cles (UAVs) is soaring due to their multiple autonomous applica- toring, geographical mapping, and performing certain danger- tions, such as aerial photography, rescue operations, surveillance, ous tasks, wherein the sensor technologies are indispensable and scientific data collection. Current sensing is critical for determining battery capacity in charging and discharging process for achieving these functions [3]–[7]. These sensors include and alerting for system fault during the flight. Shunt resistors accelerometers, tilt sensors, engine intake flow sensors, mag- and Hall-effect sensors are traditionally used in UAVs. Recently, netic sensors (electronic compasses), and current sensors [8]. magnetoresistive (MR) sensors are gaining enormous attention Among these sensors, current sensors play an important role from researchers. MR sensors tend to consume less power, and for a healthy operation of UAVs such as to prevent overcharg- they are smaller in size than the Hall-effect sensors. In this paper, a number of off-the-shelf MR sensors were investigated ing and safeguard against overcurrent [9], [10]. to evaluate the possibility of applying them for UAVs. Another Four physical principles are typically applied for current type of magnetic sensor (fluxgate) and shunt resistor was also sensors, namely Ohm’s law (shunt resistors), Faraday’s law studied and compared as a reference. -
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. -
Principles of Shunt Capacitor Bank Application and Protection
Principles of Shunt Capacitor Bank Application and Protection Satish Samineni, Casper Labuschagne, and Jeff Pope Schweitzer Engineering Laboratories, Inc. Presented at the 64th Annual Georgia Tech Protective Relaying Conference Atlanta, Georgia May 5–7, 2010 Previously presented at the 63rd Annual Conference for Protective Relay Engineers, March 2010, and 9th Annual Clemson University Power Systems Conference, March 2010 Originally presented at the 36th Annual Western Protective Relay Conference, October 2009 1 Principles of Shunt Capacitor Bank Application and Protection Satish Samineni, Casper Labuschagne, and Jeff Pope, Schweitzer Engineering Laboratories, Inc. Abstract—Shunt capacitor banks (SCBs) are used in the electrical industry for power factor correction and voltage support. Over the years, the purpose of SCBs has not changed, but as new dielectric materials came to market, the fusing practices for these banks changed from externally fused to internally fused, fuseless, and finally to unfused [1]. This paper gives a brief overview of the four most common types of SCBs. What are the differences between them? Which is the best one to use? What type of protection is best suited for each bank configuration? The paper provides a quick and simple way to calculate the out-of-balance voltages (voltage protection) or current (current protection) resulting from failed capacitor units or elements. While the identification of faulty capacitor units is easy with an externally fused bank, it is more complex with the other types of fusing, making maintenance and fault investigation difficult. This paper presents a novel method to identify the faulted phase and section in capacitor banks. Fig. 1. Four most common capacitor bank configurations I. -
Simplifying Current Sensing (Rev. A)
Simplifying Current Sensing How to design with current sense amplifiers Table of contents Introduction . 3 Chapter 4: Integrating the current-sensing signal chain Chapter 1: Current-sensing overview Integrating the current-sensing signal path . 40 Integrating the current-sense resistor . 42 How integrated-resistor current sensors simplify Integrated, current-sensing PCB designs . 4 analog-to-digital converter . 45 Shunt-based current-sensing solutions for BMS Enabling Precision Current Sensing Designs with applications in HEVs and EVs . 6 Non-Ratiometric Magnetic Current Sensors . 48 Common uses for multichannel current monitoring . 9 Power and energy monitoring with digital Chapter 5: Wide VIN and isolated current sensors . 11 current measurement 12-V Battery Monitoring in an Automotive Module . 14 Simplifying voltage and current measurements in Interfacing a differential-output (isolated) amplifier battery test equipment . 17 to a single-ended-input ADC . 50 Extending beyond the maximum common-mode range of discrete current-sense amplifiers . 52 Chapter 2: Out-of-range current measurements Low-Drift, Precision, In-Line Isolated Magnetic Motor Current Measurements . 55 Measuring current to detect out-of-range conditions . 20 Monitoring current for multiple out-of-range Authors: conditions . 22 Scott Hill, Dennis Hudgins, Arjun Prakash, Greg Hupp, High-side motor current monitoring for overcurrent protection . 25 Scott Vestal, Alex Smith, Leaphar Castro, Kevin Zhang, Maka Luo, Raphael Puzio, Kurt Eckles, Guang Zhou, Chapter 3: Current sensing in Stephen Loveless, Peter Iliya switching systems Low-drift, precision, in-line motor current measurements with enhanced PWM rejection . 28 High-side drive, high-side solenoid monitor with PWM rejection . 30 Current-mode control in switching power supplies . -
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. -
Engineering Mini Holiday Lights Series and Parallel Circuits
1 Engineering Mini Holiday Lights Jeffrey La Favre The small light bulbs we are using for our activities were cut from strings of mini holiday lights. The strings contained 100 light bulbs arranged in two sets of series circuits (50 lights in each series circuit). This paper will explore the reasons why the bulbs were designed to operate in series circuits. If your parents own strings of incandescent mini holiday lights, they might tell you they have had trouble with them after a few years of use. If a light bulb burns out or is no longer tight in its socket, all of the lights in the circuit may not glow when plugged in. It can be frustrating to find the bad bulb and replace it to repair the light string. You might ask why the lights were designed to operate in a series circuit due to this problem. In this paper I will try to explain why the lights were designed in series circuits. The explanation will include some math that might be difficult to understand. But if you look carefully at the math, you will discover that it is really nothing more than adding, subtracting, multiplying and dividing. Series and Parallel circuits After you have completed lesson one on series and parallel circuits, you should have some understanding of the way electricity behaves in these circuits. Let us review the two circuit types and cover some important points that will help you understand the rest of this paper. In a series circuit the current flows through one bulb, then the next and then the next. -
How to Choose a Shunt Resistor.Pdf
How to Choose a Shunt Resistor TI Precision Labs – Current Sense Amplifiers Presented by Rajani Manchukonda Prepared by Ian Williams and Rabab Itarsiwala 1 Hello, and welcome to the TI precision labs series on current sense amplifiers. My name is Rajani Manchukonda, and I’m a product marketing engineer for current sensing products. In this video, we will look into the primary factors that impact the choice of shunt resistor, and show how to calculate the maximum shunt resistor value for an application. We will also briefly touch upon shunt resistor tolerance error. 2 What is a shunt resistor? VS VBUS IN– VS + – OUT V R SHUNT SHUNT + - IN+ GND Iload To load 2 First, let’s define a shunt resistor, or RSHUNT. This is the resistor through which load current flows in a current sensing application. Due to Ohm’s law, a differential voltage called VSHUNT or VSENSE is developed across RSHUNT, which is then measured by a differential amplifier like a current sense amplifier. 4 Primary factors for choosing a shunt resistor 1. Minimum current accuracy 2. Maximum power dissipation – Size – Cost Shunt resistor examples 3 Selecting the value of RSHUNT is based primarily on 2 factors: 1. The required accuracy at minimum load current, and 2. The power dissipation at maximum load current, with its associated size and cost. 6 Minimum current accuracy VBUS VOS 1 mV + – + + Vsense - Iload V Offset error (%) = os ∗ 100 Vsense To load Vsense = Rshunt ∗ Iload 4 Now let me explain how to determine minimum current accuracy for a current sensing application. For simplicity, we will only consider the amplifier’s offset error in this case and ignore other error sources which will be discussed in later videos.