DOCSLIB.ORG

8 Circuit Measurement

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
8 Circuit Measurement Air Washington Electronics – Direct Current 8 Circuit Measurement This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this license, visit http://creativecommons.org/licenses/by/3.0/. Air Washington is an equal opportunity employer/program. Auxiliary aids and services are available upon request to individuals with disabilities. This workforce solution was funded (100%) by a grant awarded by the U.S. Department of Labor’s Employment and Training Administration. The solution was created by the grantee and does not necessarily reflect the official position of the U.S. Department of Labor. The Department of Labor makes no guarantees, warranties, or assurances of any kind, express or implied, with respect to such information, including any information on linked sites and including, but not limited to, accuracy of the information or its completeness, timeliness, usefulness, adequacy, continued availability, or ownership. This solution is copyrighted by the institution that created it. Internal use, by an organization and/or personal use by an individual for non-commercial purposes is permissible. All other uses require the prior authorization of the copyright owner. Revised: Thursday, May 15, 2014 Page 1 of 80 Air Washington Electronics – Direct Current Contents 8 Circuit Measurement ................................................................................................................... 1 Introduction to Circuit Measurement............................................................................................. 5 What is a meter? ......................................................................................................................... 5 In-Circuit Meters ...................................................................................................................... 6 Out-of-Circuit Meters .............................................................................................................. 6 Knowledge Check ........................................................................................................................ 7 Basic Meter Movements ................................................................................................................. 7 Permanent-Magnet Moving-Coil Movement .............................................................................. 8 Knowledge Check ...................................................................................................................... 14 Ammeters...................................................................................................................................... 15 Why Ammeters are Connected in Series .................................................................................. 15 Ammeter Sensitivity .................................................................................................................. 17 Ammeter Ranges ....................................................................................................................... 17 Knowledge Check ...................................................................................................................... 21 Other Ammeters ....................................................................................................................... 21 Ammeter Safety Precautions .................................................................................................... 23 Knowledge Check................................................................................................................... 23 Ammeter design ............................................................................................................................ 24 Multiple Range Ammeters ........................................................................................................ 27 Other Methods of Measuring Current ...................................................................................... 29 Voltmeters .................................................................................................................................... 32 Why voltmeters are connected in parallel ................................................................................ 32 Loading Effect ............................................................................................................................ 33 Knowledge Check ...................................................................................................................... 34 Sensitivity of Voltmeters ........................................................................................................... 35 Page 2 of 80 Air Washington Electronics – Direct Current Ranges ....................................................................................................................................... 37 Knowledge Check ...................................................................................................................... 40 Voltmeter Safety Precautions ................................................................................................... 40 Knowledge Check................................................................................................................... 40 Other Voltmeters ...................................................................................................................... 41 Electrostatic Meter Movements ............................................................................................... 41 Voltmeter design........................................................................................................................... 41 Ohmmeters ................................................................................................................................... 48 Using the Ohmmeter ................................................................................................................. 50 Ohmmeter Ranges .................................................................................................................... 51 Knowledge Check ...................................................................................................................... 53 Shunt Ohmmeter ....................................................................................................................... 53 Ohmmeter Safety Precautions ................................................................................................. 55 Knowledge Check................................................................................................................... 56 Megohmmeter .......................................................................................................................... 56 Ohmmeter design...................................................................................................................... 57 Bridge circuits ............................................................................................................................ 63 Example ..................................................................................................................................... 65 Labs for Circuit Measurement ...................................................................................................... 67 Overview ................................................................................................................................... 67 Requirements ............................................................................................................................ 67 Course Objectives ...................................................................................................................... 67 Module Objectives .................................................................................................................... 67 Activities & Assessments ........................................................................................................... 67 1: Analog Voltmeter ..................................................................................................................... 68 Page 3 of 80 Air Washington Electronics – Direct Current Components .............................................................................................................................. 68 Circuit Diagram .......................................................................................................................... 68 Procedure .................................................................................................................................. 68 Observations & Conclusions ...................................................................................................... 69 2: Analog Current Meter .............................................................................................................. 70 Components .............................................................................................................................. 70 Circuit diagram .......................................................................................................................... 70 Procedure .................................................................................................................................. 71 Observations & Conclusions ...................................................................................................... 71 Answers to Knowledge Checks ....................................................................................................
Load more

Recommended publications
  • 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.
    [Show full text]
  • 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.
    [Show full text]
  • Full Procedure List
    PO Box 111113 Aurora, CO 80042 Phone 303.317.6670 [email protected] World’s Largest MET/CAL® Library! Cal Lab Solutions prides itself on developing the very best automated procedures in the industry. We develop solutions to address your lab’s unique requirements and are dedicated to finding the most cost- effective solution that meets your needs. One of the many services we provide includes the development of MET/CAL® procedures. We offer both off the shelf procedures matching the manufacturer’s written documentation and custom solutions based on the documentation of your choice. Below is a list of procedures ready for delivery. If you do not see what you’re looking for, please feel free to call or email for an immediate quote. MANUFACTURER MODEL DESCRIPTION Generic Caliper All Calipers Generic Micrometer All Micrometers Generic Pin Gauges All Pin Gauges Generic Torque Wrench All Torque Wrenches Generic Decade Resistor All Decade Resistors Acqiris DC265 PXI High Speed Waveform Analyzer Acqiris DC270 PXI High Speed Waveform Analyzer Acqiris DC271 PXI High Speed Waveform Analyzer Advantest R3131A Spectrum Analyzer Advantest R3261C Spectrum Analyzer Advantest R3261D Spectrum Analyzer Advantest R3265A Spectrum Analyzer Advantest R3271A Spectrum Analyzer Advantest R3361C Spectrum Analyzer Advantest R3361D Spectrum Analyzer Aeroflex 2023 Signal Generator Aeroflex 2024 Signal Generator Agilent/HP 16530A/31A Oscilloscope Module Agilent/HP 16532A Oscilloscope Module Agilent/HP 16533A Oscilloscope Module Agilent/HP 16534A Oscilloscope Module
    [Show full text]
  • 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.
    [Show full text]
  • Energy and Power Meters Catalogue for Panel Builders
    Schneider Electric Energy and power meters catalogue for Panel Builders www.schneider-electric.com Schneider Electric Energy and power meters catalogue for panel builders Contents Introduction 3 Selection guide panorama 4 Current transformers 7 Panel instruments 18 Basic energy metering IEM2000 series, IEM3000 series 29 Basic multi-function metering PM3000 series, PM5000 series 43 Communications and gateways Link150, Com’X 200, Com’X 210, Com’X 510 59 Commercial reference numbers See your Schneider Electric representative for complete ordering information. 76 Clicking on a Commercial Reference Number or scanning the product’s QR Code links you to further product information on www.schneider-electric.com www.schneider-electric.com PANEL BUILDERS CATALOGUE FUNCTIONS AND CHARACTERISTICS Why Panel Builders Choose Schneider Electric? Schneider Electric is the global specialist in energy management and as such it has the most complete power motoring product line, going from simple indicators (analogue meters) and CTs, to world class accurate energy meters and powerful compact power meters. These proven products come with multiple options to satisfy any requirement. Schneider Electric products are safe and reliable. We comply with the most stringent standards, including IEC, MID, UL, etc., and we thoroughly test all products with third-party laboratories. This gives our partners the peace of mind and the confidence that they are maintaining a good reputation while delivering the best value in equipment and service to their customers. Our products are simple to install, configure, and use. This saves our partners time and money and lets them deliver the best solutions in a timely and cost-effective manner.
    [Show full text]
  • Compact Current Reference Circuits with Low Temperature Drift and High Compliance Voltage
    sensors Article Compact Current Reference Circuits with Low Temperature Drift and High Compliance Voltage Sara Pettinato, Andrea Orsini and Stefano Salvatori * Engineering Department, Università degli Studi Niccolò Cusano, via don Carlo Gnocchi 3, 00166 Rome, Italy; [email protected] (S.P.); [email protected] (A.O.) * Correspondence: [email protected] Received: 7 July 2020; Accepted: 25 July 2020; Published: 28 July 2020 Abstract: Highly accurate and stable current references are especially required for resistive-sensor conditioning. The solutions typically adopted in using resistors and op-amps/transistors display performance mainly limited by resistors accuracy and active components non-linearities. In this work, excellent characteristics of LT199x selectable gain amplifiers are exploited to precisely divide an input current. Supplied with a 100 µA reference IC, the divider is able to exactly source either a ~1 µA or a ~0.1 µA current. Moreover, the proposed solution allows to generate a different value for the output current by modifying only some connections without requiring the use of additional components. Experimental results show that the compliance voltage of the generator is close to the power supply limits, with an equivalent output resistance of about 100 GW, while the thermal coefficient is less than 10 ppm/◦C between 10 and 40 ◦C. Circuit architecture also guarantees physical separation of current carrying electrodes from voltage sensing ones, thus simplifying front-end sensor-interface circuitry. Emulating a resistive-sensor in the 10 kW–100 MW range, an excellent linearity is found with a relative error within 0.1% after a preliminary calibration procedure.
    [Show full text]
  • The Voltage Divider
    Book Author c01 V1 06/14/2012 7:46 AM 1 DC Review and Pre-Test Electronics cannot be studied without first under- standing the basics of electricity. This chapter is a review and pre-test on those aspects of direct current (DC) that apply to electronics. By no means does it cover the whole DC theory, but merely those topics that are essentialCOPYRIGHTED to simple electronics. MATERIAL This chapter reviews the following: ■■ Current flow ■■ Potential or voltage difference ■■ Ohm’s law ■■ Resistors in series and parallel c01.indd 1 6/14/2012 7:46:59 AM Book Author c01 V1 06/14/2012 7:46 AM 2 CHAPTER 1 DC REVIEW AND PRE-TEST ■■ Power ■■ Small currents ■■ Resistance graphs ■■ Kirchhoff’s Voltage Law ■■ Kirchhoff’s Current Law ■■ Voltage and current dividers ■■ Switches ■■ Capacitor charging and discharging ■■ Capacitors in series and parallel CURRENT FLOW 1 Electrical and electronic devices work because of an electric current. QUESTION What is an electric current? ANSWER An electric current is a flow of electric charge. The electric charge usually consists of negatively charged electrons. However, in semiconductors, there are also positive charge carriers called holes. 2 There are several methods that can be used to generate an electric current. QUESTION Write at least three ways an electron flow (or current) can be generated. c01.indd 2 6/14/2012 7:47:00 AM Book Author c01 V1 06/14/2012 7:46 AM CUrrENT FLOW 3 ANSWER The following is a list of the most common ways to generate current: ■■ Magnetically—This includes the induction of electrons in a wire rotating within a magnetic field.
    [Show full text]
  • Super Megohmmeter Sm-8200 Series
    SM-8200 SERIES SUPER MEGOHMMETER d Tim de er, Larg splay -loa com e LCD digital/analog di fully parator ctions , remote start & communication fun 2 l Digital numeric readout with virtual analog display. Easy-to- use combined digital-analog models*1 l Timer, comparator, remote start and command functions included as standard features to support new applications*1 l Many safety-enhancing features Display Features 1– Clear, three-mode liquid crystal display*1 Bright LCD simultaneously displays data in three modes: quasi-bar-graph, virtual needle and numeric values. 2– Clear graduated scale and precise data reading*1 The one-line graduated scale is always visible, and scales automatically according to the selected measurement voltage. Data is held on the display after measuring, so there is no hurry to read it. The numeric readout displays measured values at maximum resolution. 3– Enhanced response speed and reliability*1 Reliability is enhanced because, unlike analog meters, the LCD has no moving parts, and the virtual needle responds seven times faster than a mechanical needle. Installation in automated systems is supported. Usability Features 1– Timer function included as a standard feature*1 The need for counting complicated measurement time (by stopwatch) is eliminated. Timer settings are retained in internal memory even when power is turned off. 2– Comparator functions included as a standard feature*1 Easy-to-use GO/NO-GO (Pass/Fail) decisions NO-GO (Fail) decisions can be indicated by an alarm sound simultaneously with contact output. Comparator settings are retained even when power is turned off. 3– Remote Start function included as a standard feature*1 Measurement can be started hands-free, using a footswitch or trigger signal.
    [Show full text]
  • 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.
    [Show full text]
  • Megger Electrical Test Instruments Catalog
    Megger 5/10-kV Insulation Test Equipment ................ 2 Electrical Test 1-kV Insulation Test Equipment ..................... 6 Additional Insulation Test Equipment ......... 11 Instruments Ground Resistance Test Equipment ............. 13 AC Loop Impedance Testers ......................... 17 Catalog Digital Low Resistance Ohmmeters ............. 18 Multimeters ................................................... 22 Clampmeters ................................................. 23 Time Domain Reflectometers ....................... 24 Datacom Test Equipment .............................. 26 Substation Test Equipment .......................... 27 Battery Impedance Test Equipment ............. 28 Special Maintenance Equipment ................. 30 Safety Test Equipment .................................. 34 Test and Measurement Software ................. 35 Cross Reference Guide .................................. 36 Valley Forge Corporate Center 2621 Van Buren Avenue TOLL FREE Norristown, PA 19403-2329 USA CUSTOMER SERVICE NUMBER Phone: 866-254-0962 Phone: 610-676-8500 WWW.MEGGER.COM/US Fax: 610-676-8610 1-866-254-0962 WWW.MEGGER.COM/US Contact us regarding questions, customer service and product repairs The word “Megger” is a registered trademark MEG-19961/18.5/M/2.2010 Megger 1-kV Insulation Testers… … Consist of a range of instruments for varying needs and budgets … Provide end users with more testing capability … Offer a rock solid design, making these instruments the best value proposition on the market today Look inside for information
    [Show full text]
  • 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.
    [Show full text]
  • A Self-Balancing Direct-Current Bridge for Accurate Bolometric Power Measurements
    --------------------- Journal of Research of the National Bureau of Standards Vol . 59, No.2, August 1957 Research Paper 2776 A Self-Balancing Direct-Current Bridge for Accurate Bolometric Power Measurements Glenn F. Engen Un til recently, the most accurate microwave power measurements of the bolometri c t ype have required t he use of a manual d-c bridge. A self-ba lan cin g d-c bridge h as bee n developed t hat preserves t he inheren t accuracy of t he m anual bridge, extends the d y namic range of operation, and greatly simplifies t he operating procedure. A general descrip t. ion of the equipment and operating techniques is given, followed b.v it co mprehensiv e survey of t he sources of error accompanyin g t Ile m ethod a nd t he accuracy achieved . 1. Introduction con tains a random el'l'Ol' of ± 0.005 percen t , it can be shown that for a Lypical bolometer operating at A large amount of th e research effor t expendrd in 200 ohms and requiring 8.5 ma of bifLs (i l = 17 m a) tl10 field of 101'1 level microwave power measurement the error in measuring Prr m ay b e as large as 0.02 , in the past few years has beel1 direcLe d toward a 0. 3, a nd 3 percent at the 10, ], alld 0.1 mw level s, rc­ detC'rmination of bolometer-mount effi ciencies, or spectively , if all oLher sources of rno]' arc neglected. evaluation of lli e validity of the r-f- d-c substitution Tbe small difference beLween it a nd 'i2 at low lcyels pri Ilci plc.
    [Show full text]