DOCSLIB.ORG

Bodine Electric Gearmotor Handbook

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Bodine Electric Gearmotor Handbook Courtesy of Steven Engineering, Inc - (800) 258-9200 - [email protected] - www.stevenengineering.com For up-to-date product information, 2D/3D CAD drawings and detailed specifications, please visit www.bodine-electric.com About Us Bodine Electric Company offers over 1,200 standard products, and thousands of custom designed fractional horsepower (<746 Watts) gearmotors, motors and motion controls (fixed and variable speed AC, brushless DC, and permanent magnet DC). Bodine products are available via an extensive distributor network or sold directly to OEMs. Known for their reliability, long life and competitive prices, Bodine gearmotors and motors are designed for demanding industrial and commercial applications such as medical devices, scientific and laboratory equipment, labeling equipment, printing presses, packaging equipment, factory automation, and mobile and solar powered equipment. Bodine Electric is headquartered in Northfield, Illinois (20 miles north of Chicago) with manufacturing and assembly operations in Peosta, Iowa, U.S.A. Our quality management system is certified to ISO 9001:2008. MANAG Bodine Electric Company ITY GEE LLI M A EE UU NN 201 Northfield Road QQ TT D D SS EE I Y I Y F F Northfield, Illinois 60093 U.S.A. S S I I T T T T E E R R ISO M M E ISO E C www.bodine-electric.com C 9001:2008 [email protected] Phone: 773.478.3515 Copyright Notice: Small Gearmotors, Motors, and Controls Handbook ©2016 Bodine Electric Company. All rights reserved. Unauthorized duplication, distribution, or modification of this publication, in part or whole, is expressly prohibited. ISBN 9994675133. Library of Congress Catalog Number 92-076079. Courtesy of Steven Engineering, Inc - (800) 258-9200 - [email protected] - www.stevenengineering.com Contents Page 1 Electric Motor Fundamentals Basic Electricity . .1-1 Basic Magnetism . 1-6 Generators and Basic AC Circuits . .1-12 Basic Mechanical Principles . 1-20 2 AC Motors AC Motor Action . .2-1 Polyphase (Two or More Phases) Motors . 2-2 Single-Phase . .2-5 Single-Phase AC Motor Types . .2-5 Synchronous (Polyphase and Single-Phase) . 2-12 3 Commutator (DC) Motors Brush-Type DC Motor Action . .3-1 Brush-Type DC Motors . 3-3 Brushless DC Motor Action . .3-11 4 Special Purpose Motors Fractional Horsepower Gearmotors . .4-1 Low Speed AC Synchronous Motors . .4-2 Torque Motors . 4-3 Switched Reluctance Motors . .4-6 Linear Induction Motors . 4-7 DC and AC Servo Motors . 4-8 Shell-Type Armature Motor . .4-9 Printed Circuit (PC) Motor . 4-10 5 Basic Motor Construction Magnetic Materials and Motor Design . 5-1 Bearings . .5-6 Brushes . .5-9 Insulation Systems . .5-12 Environmental Protection . 5-13 6 Gearhead Construction Gearing . .6-1 Gear Trains . .6-4 Gearmotor Lubrication . .6-6 7 Motor/Gearmotor Selection and Application Motor and Gearmotor Industry Standards . .7-1 Motor and Gearmotor Nameplate Ratings . .7-3 Noise and Vibration . .7-10 Thermal Protection . .7-16 Energy Management . 7-19 Load Torque Measurement . 7-22 Motor Sizing . 7-24 Application Guidelines . 7-25 Safety . .7-40 Care and Servicing . .7-42 Courtesy of Steven Engineering, Inc - (800) 258-9200 - [email protected] - www.stevenengineering.com 8 Motor Controls Motion Control Systems . .8-2 Motor Operating Characteristics . .8-5 Motor Control Types . 8-12 Passive Device Motor Controls . 8-13 Solid State Electronic (Active) Motor Controls . .8-21 Solid State Electronic (Active) Control of AC Motors . 8-39 Motor Control Enclosure Standards . .8-42 9 Feedback Devices Tachometer Generators . 9-2 Encoders . .9-2 10 Clutches and Braking Techniques Electromechanical Clutches and Brakes . .10-1 Dynamic Braking . .10-7 Evaluation of Dynamic Braking Methods . 10-18 Appendix 1 List of Associations and Standards Organizations . A-1 2 Troubleshooting fhp Motors . .A-2 3 Helpful Shortcuts . .A-4 4 Motor Application Formulae . A-6 5 Properties of Materials . .A-8 6 Temperature Conversions . .A-9 7 SI (Metric) Conversion Table . A-10 8 Typical Gearmotor Construction . .A-11 9 Horsepower/Watts vs . Torque Conversion Chart . .A12 10 Specific Resistance of Metals and Alloys at Ordinary Temperatures . .A-17 11 NEMA Motor Frame Dimensions . A-18 12 International Voltage and Frequency Standards . A-19 Glossary . .G-1 Connection Diagrams . .CD-1 Index . .IN-1 Final Review . FR-1 Courtesy of Steven Engineering, Inc - (800) 258-9200 - [email protected] - www.stevenengineering.com Electric Motor Fundamentals Electric motors are designed to convert 1.1 BASIC electrical energy into mechanical energy to perform some physical task or work. In ELECTRICITY order to understand the types of motors that are available as well as their perfor- Electric Current (I) mance characteristics, some understanding Atomic theory describes matter as an of the basic physical principles governing aggregate of atoms. Each atom consists of motor design and operation are required. a nucleus containing positively charged Basic electric motor design encompass- protons and electrically neutral particles es the laws of electricity and magnetism. called neutrons. Revolving in orbits around Motor feedback and control systems in- the positive nucleus are negatively charged volve semiconductor devices, micropro- electrons. cessors and other elements of electronics. In metallic conductors (such as copper), And no discussion of motors would be one or more electrons from the outer orbits complete without a brief understanding of become detached from each atom and the mechanical principles governing linear move randomly from one atom to another. and angular motion. These are called free electrons. The posi- This Chapter of the Handbook pro- tive nucleus and the rest of the electrons vides an overview of these fundamentals so remain relatively fixed in position. Insula- that the reader will have a foundation on tors, on the other hand, contain virtually no which to build a better understanding of free electrons. motor design and performance specifica- When an electric field is applied to a tions. conductor, free electrons will drift under the influence of that electric field. Drifting electrons will collide with stationary atoms 1-1 Courtesy of Steven Engineering, Inc - (800) 258-9200 - [email protected] - www.stevenengineering.com causing additional free electrons to drift in between the two points results in a power the same direction. This movement of elec- dissipation of one watt. tric charge is called current. The unit of measurement for current or Resistance (R) rate of charge flow is the ampere. We Resistance is defined as the opposition speak of a direct current (DC) if the charg- to current flow. Although electrons may es always flow in the same direction, even flow in any substance, different materials though the amount of charge flow per unit offer different resistance to their flow. time may vary. If the flow of charge revers- Those which make the transfer of elec- es its direction periodically, then we have trons relatively easy are called conductors what is called alternating current (AC). A (copper, aluminum, steel, etc.), and those more detailed description of direct and which tend to impose substantial resistance alternating current is presented in Section are called insulators (wood, paper, mica, 1.3 of this Chapter. glass, etc.). Materials with a level of con- Conventional Current Flow: ductivity between these two extremes are Before the acceptance of the electron the- called semiconductors (germanium, sili- ory, it was assumed that the direction of con). These “inbetween” materials have current flow was from a positively charged become increasingly useful in the applica- body to a negatively charged body. This tion of electrical energy. positive to negative flow of current is called The unit of electrical resistance is the Ω conventional current flow. However, in a ohm ( ). One ohm is defined as the resis- metallic conductor, it is electrons that carry tance of a conductor which will allow a the charge from negative to positive. The current flow of one ampere when a poten- flow of current from negative to positive is tial difference of one volt is applied. The called electron flow. We will adopt con- resistance of a material is normally depen- ventional current flow throughout this dent on temperature. In general, the resis- Handbook. In the diagrams, the direction tance of metallic conductors increases with of current will always be from positive to temperature. negative. Ohm’s Law: Ohm’s law explains the relationship between voltage, current Potential Difference (V) and resistance. It states that the amount of Electrons will move between two points current through a conductor is directly pro- of a conductor if there is a potential differ- portional to voltage applied and inversely ence (or a difference of “electric pressure”) proportional to the resistance of the con- between the two points. Voltage is the ductor or circuit: measure of the amount of pressure needed V I = --- to push electrons through a conductor. It is R analogous to a water pump that maintains a pressure difference between its inlet and A conductor obeys Ohm’s law when, outlet and results in water flow. Potential for a given temperature, the current it con- difference and voltage are often used inter- ducts varies linearly with the applied volt- changeably. age (Fig. 1-1). The unit of potential difference or volt- Power: Electricity is used to perform age is the volt. A potential difference of some type of work or to generate heat. one volt will be dropped across two points Power is the rate at which work is done or if a constant current of one ampere flowing the rate at which heat is generated. The unit 1-2 Courtesy of Steven Engineering, Inc - (800) 258-9200 - [email protected] - www.stevenengineering.com Fig. 1-1: Current varies linearly with Fig. 1-2: Simplified series circuit. applied voltage in accordance with Ohm’s law. curremt flow.
Load more

Recommended publications
  • The Performance of a Special Repulsion Motor in A
    THE PERFORMANCE OF A SPECIAL REPULSION MOTOR IN A CLOSED-LOOP POSITIONING SYSTEM A THESIS Presented to the Faculty of the Graduate Division by Eugene Dale McCalia In Partial Fulfillment of the Requirements for the Degree Master of Science in Electrical Engineering Georgia Institute of Technology June, 1959 "In presenting the dissertation as a partial fulfillment of the requirements for an advanced degree from the Georgia Institute of Technology, I agree that the Library of the Institution shall make it available for inspection and circulation in accordance with its regulations governing materials of this type. I agree that permission to copy from, or to publish from, this dissertation may be granted by the professor under whose direction it was written, or, in his absence, by the dean of the Graduate Division when such copying or publication is solely for scholarly purposes and does not involve potential financial gain. It is understood that any copying from, or publication of, this dissertation which involves potential financial gain will not be allowed without written permission. THE PERFORMANCE OF A SPECIAL REPULSION MOTOR IN A CLOSED-LOOP POSITIONING SYSTEM Approved: Z2^__ ^ L.J& a M. Date of Approval: )vkv ^-6 ~ l<i^c/ .J- ...... ' •' ' "t' 11 ACKNOWLEDGMENTS The author wishes to acknowledge with appreciation his indebted­ ness to Dr. F. 0. Nottingham, Jr. who suggested the problem and also for the assistance and encouragement that he so cheerfully contributed throughout the course of this study, To my wife, I express appreciation for her love, patience and understanding and also for her assistance and encouragement in the preparation of the final draft.
    [Show full text]
  • POWER ELECTRONICS TRAINER (Model : XPO-PE) / MICROCONTROLLER BASED PE (Model : XPO-Μc LSPT)
    POWER ELECTRONICS TRAINER (Model : XPO-PE) / MICROCONTROLLER BASED PE (Model : XPO-µC LSPT) SALIENT FEATURES u Aesthetically designed injection molded electronic desk. u Master unit carrying useful experiment resources like line Synchronized firing circuits, Power supplies, lamp load, RLC loads, Battery charging supply etc. while the central slot will hold replaceable experiment panels. u Each multi experiment panel is secured in an ABS molded plastic sturdy enclosure, and has colorful screw less overlay showing circuit & Connection through Sturdy 4mm Banana Sockets & Patch Chords. u Set of User Guide provided with each unit. u Order 6 Master units and set of 6 panels (PE 1 x 2 , PE2, PE3, PE6X2nos)+ Power scope, buy more of PE1 and PE6 being major panels. Master Unit Accessories: Built in power supply l 15 pin D connector cable assembly, u DC supply : + 12V, 500mA, l 4mm patchcords : 100mm X 10 Nos & 500mm X 20 Nos. u Unregulated Power supply 17V / 750mA, Optional Power Scope u Regulated 7VDC to 14VDC/3A O/P is provided as 12V Battery charging supply. In absence of battery, same may be used as simulated battery source to run experiments on inverters etc. u Isolated DC supply +12V/ 300mA with isolated common. u On board Inverter transformer of Primary & Secondaries: 12-11-0- 11-12/3A. u On board o/p to Isolated Drive Circuit AC supply u 230V AC line voltage is made available on two banana 4mm Accessory for any Lab CRO for off ground differential measurements sockets as well as 1.5A fuse extender for variac if used.
    [Show full text]
  • Brushless DC Electric Motor
    Please read: A personal appeal from Wikipedia author Dr. Sengai Podhuvan We now accept ₹ (INR) Brushless DC electric motor From Wikipedia, the free encyclopedia Jump to: navigation, search A microprocessor-controlled BLDC motor powering a micro remote-controlled airplane. This external rotor motor weighs 5 grams, consumes approximately 11 watts (15 millihorsepower) and produces thrust of more than twice the weight of the plane. Contents [hide] 1 Brushless versus Brushed motor 2 Controller implementations 3 Variations in construction 4 AC and DC power supplies 5 KM rating 6 Kv rating 7 Applications o 7.1 Transport o 7.2 Heating and ventilation o 7.3 Industrial Engineering . 7.3.1 Motion Control Systems . 7.3.2 Positioning and Actuation Systems o 7.4 Stepper motor o 7.5 Model engineering 8 See also 9 References 10 External links Brushless DC motors (BLDC motors, BL motors) also known as electronically commutated motors (ECMs, EC motors) are electric motors powered by direct-current (DC) electricity and having electronic commutation systems, rather than mechanical commutators and brushes. The current-to-torque and frequency-to-speed relationships of BLDC motors are linear. BLDC motors may be described as stepper motors, with fixed permanent magnets and possibly more poles on the rotor than the stator, or reluctance motors. The latter may be without permanent magnets, just poles that are induced on the rotor then pulled into alignment by timed stator windings. However, the term stepper motor tends to be used for motors that are designed specifically to be operated in a mode where they are frequently stopped with the rotor in a defined angular position; this page describes more general BLDC motor principles, though there is overlap.
    [Show full text]
  • Universal Motor - Construction, Working and Characteristics
    Universal Motor - construction, working and characteristics. A universal motor is a special type of motor which is designed to run on either DC or single phase AC supply. These motors are generally series wound (armature and field winding are in series), and hence produce high starting torque (See characteristics of DC motors here). That is why, universal motors generally comes built into the device they are meant to drive. Most of the universal motors are designed to operate at higher speeds, exceeding 3500 RPM. They run at lower speed on AC supply than they run on DC supply of same voltage, due to the reactance voltage drop which is present in AC and not in DC. There are two basic types of universal motor : (i)compensated type and (ii) uncompensated type. Construction of Universal motor Construction of a universal motor is very similar to the construction of a DC machine. It consists of a stator on which field poles are mounted. Field coils are wound on the field poles. However, the whole magnetic path (stator field circuit and also armature) is laminated. Lamination is necessary to minimize the eddy currents which induce while operating on AC. The rotary armature is of wound type having straight or skewed slots and commutator with brushes resting on it. The commutation on AC is poorer than that for DC. because of the current induced in the armature coils. For that reason brushes used are having high resistance. Working of universal motor A universal motor works on either DC or single phase AC supply. When the universal motor is fed with a DC supply, it works as a DC series motor.
    [Show full text]
  • UNIVERSAL MOTORS Universal Motor
    UNIVERSAL MOTORS Universal motor The motors which can be used with a single phase AC source as well as a DC source of supply and voltages are called as Universal Motor. It is also known as Single Phase Series Motor. A universal motor is a commutation type motor. Construction of the universal motor The construction of the universal motor is same as that of the series motor. I n o rd e r t o m i n i m i z e t h e p ro b l e m o f commutation, high resistance brushes with increased brush area are used. To reduce Eddy current losses the stator core and yoke are laminated. The Universal motor is simple and less costly. It is used usually for rating not greater than 7 5 0 W . Characteristic of Universal motor The characteristic of Universal motor is similar to that of the DC series motor. When operating from an AC supply, the series motor develops less torque. By interchanging connections of the fields with respect to the armature, the direction of rotation can be altered. Universal motor T h e d i r e c t i o n o f t h e developed torque will re m a i n p o s i t i v e , a n d direction of the rotation will be as it was before. The nature of the torque will be pulsating, and the frequency will be twice that of line frequency as shown in the waveform. Universal motor Thus, a Universal motor can work on both AC and DC.
    [Show full text]
  • Design and Simulation of Leakage Current in Smart Power Module (Spm) Motor Drive Application
    View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by UTHM Institutional Repository DESIGN AND SIMULATION OF LEAKAGE CURRENT IN SMART POWER MODULE (SPM) MOTOR DRIVE APPLICATION SYAHFITRI BIN SAIDIN A project report submitted in partial fulfillment of the requirement for the award of the Degree of Master of Electrical Engineering Faculty Of Electrical And Electronics Engineering Universiti Tun Hussein Onn Malaysia DECEMBER 2013 vi CONTENTS TITLE i DECLARATION ii DEDICATION iii ACKNOWLEDGEMENT iv ABSTRACT v CONTENTS vi LIST OF FIGURES x LIST OF TABLES xiv LIST OF SYMBOL AND ABBREAVIATION xv LIST OF APPENDIXES xvi CHAPTER 1 INTRODUCTION 1.1 General Background of Electric Motor 1 1.2 Universal Motor 3 1.2.1 Properties of Universal Motor 4 1.2.2 Applications of Universal Motor 6 1.3 DC Motor 7 1.3.1 Brush DC Motor 8 1.3.2 Brushless DC Motor 9 1.3.3 Permanent Magnet Stators 9 1.4 Smart Power Module (SPM) 10 1.5 Problem Statement 12 vii 1.6 Objectives and Scopes 1.6.1 Objective 13 1.6.2 Scope of Work 14 1.6.3 Thesis Overview 14 CHAPTER 2 LITERATURE REVIEW 2.1 Introduction 16 2.2 What Is Leakage Current? 16 2.2.1 Why Is It Important? 17 2.2.2 What Causes Leakage Current? 17 2.2.3 What Is A Safe Level 18 2.3 Direct Current Motor (Dc Motor) 19 2.3.1 Principle Of Dc Motor 19 2.3.2 Detailed Description Of A Dc Motor 21 2.3.3 Working Or Operating Principle Of Dc Motor 23 2.3.4 Construction Of Dc Motor 28 2.3.5 Permanent Magnet Stators 29 2.3.6 Electrical Connections Between The Stator And Rotor 30 2.4 Electricity Consumption By Electrical Motor Systems 31 2.5 Motor Efficiency 33 2.6 Brushless DC Motors (BLDC) 35 2.6.1 Brushless Vs.
    [Show full text]
  • Brush DC Motor Runs Along Dan Jones, Incremotion Associates
    TECHNICAL Brush DC Motor Runs Along Dan Jones, Incremotion Associates Everything started in 1800 when Volta developed the first DC battery. Fara- day used the DC battery to develop the first electric motor. It used brushes to transfer the battery voltage and cur- rent to the rotating disk rotor. This was in mid-1831. Thus was born the brush DC motor. Construction The slotted brush DC motor of today comes in two basic configurations: the wound field DC motor and the perma- nent magnet DC motor. The key parts of a DC motor include the armature (the rotating part), the field (either a cop- per winding or permanent magnet), and a mechanical commutation sys- tem consisting of a slotted commutator, mechanical brushes with copper wires connecting to outside terminals. The commutator is connected to various windings in a sequential pattern. The two brushes ride on the commutator to connect to the battery or outside power source via the terminals as shown in Figure 1. These brush DC motor types are called slotted or iron core types. Motor Operation The DC motor is the simplest motor type. Raise the input voltage and the motor speeds up. Lower the voltage and it reduces speed. Increase the mo- tor’s shaft load and shaft torque and armature current go up while the speed goes down. The permanent magnet DC motor is the most popular type, replac- ing the three wound field DC motors in many applications. Today the most Figure 1 Permanent magnet DC motor structure. popular wound field DC motor has an- other name—the universal motor—a separate motor type because it can be driven by AC and DC input power.
    [Show full text]
  • Single-Phase Motors
    mywbut.com Chapter (9) Single-Phase Motors Introduction As the name suggests, these motors are used on single-phase supply. Single- phase motors are the most familiar of all electric motors because they are extensively used in home appliances, shops, offices etc. It is true that single- phase motors are less efficient substitute for 3-phase motors but 3-phase power is normally not available except in large commercial and industrial establishments. Since electric power was originally generated and distributed for lighting only, millions of homes were given single-phase supply. This led to the development of single-phase motors. Even where 3-phase mains are present, the single-phase supply may be obtained by using one of the three lines and the neutral. In this chapter, we shall focus our attention on the construction, working and characteristics of commonly used single-phase motors. 9.1 Types of Single-Phase Motors Single-phase motors are generally built in the fractional-horsepower range and may be classified into the following four basic types: 1. Single-phase induction motors (i) split-phase type (ii) capacitor type (iii) shaded-pole type 2. A.C. series motor or universal motor 3. Repulsion motors (i) Repulsion-start induction-run motor (ii) Repulsion-induction motor 4. Synchronous motors (i) Reluctance motor (ii) Hysteresis motor 9.2 Single-Phase Induction Motors A single phase induction motor is very similar to a 3-phase squirrel cage induction motor. It has (i) a squirrel-cage rotor identical to a 3-phase motor and (ii) a single-phase winding on the stator.
    [Show full text]
  • Compensated Repulsion Motor  Repulsion-Start Induction-Run Motor  Repulsion Induction Motor Types of Repulsion Motor
    Introduction Construction of Repulsion Motor Types of Repulsion Motor Advantage of Repulsion Motor Disadvantage of Repulsion Motor Application of Repulsion motors Repulsion motors are classified under single phase motors. In magnetic repulsion motors the stator windings are connected directly to the ac power supply and the rotor is connected to commutator and brush assembly, very similar to that of DC armature. Repulsion Motor Construction of Repulsion Motor: Repulsion motors are based on the principle of repulsion between two magnetic fields. Consider a 2-pole motor with a vertical magnetic axis. The armature is connected to a commutator and brushes. The brushes are short circuited using a low-resistance jumper. When alternating current is supplied to the field (stator) winding, it induces an electromotive force (emf) in the armature. Construction of Repulsion Motor: The direction of alternating current is such that it creates a north pole at the top and a south pole at the bottom. The direction of induced emf is given by Lenz's law, according to which the direction of induced emf opposes the cause producing it. The induced emf induces current in the armature conductors and the direction of the induced current depends on the position of the brushes. Circuit-diagram of Repulsion motor Types of Repulsion Motor The various types of motors which works under the repulsion principle are : Compensated repulsion motor Repulsion-start Induction-run motor Repulsion Induction motor Types of Repulsion Motor Compensated repulsion motor : • It carries an additional winding, called compensating winding. • There is another set of two brushes which are placed midway between the usual short circuit brush set.
    [Show full text]
  • AN422 Improved Universal Motor Drive
    ® APPLICATION NOTE Improved Universal Motor Drive JM. BOURGEOIS, JM. CHARRETON, P. RAULT INTRODUCTION Universal motors are mostly operated in AC current mode and are controlled by means of TRIACS. This widespread solution leads to a cheap electronic controller board but has some drawbacks. In particular the high peak to peak current gives poor motor efficiency and the consequential high brush temperature leads to limited motor lifetime. When operating in DC mode, significant improvements are obtained. The RMS and peak to peak current of the motor are smaller, reducing Iron losses and brush temperature. Operating in DC mode enables shrinking of the motor size, and increasing the motor lifetime. Furthermore, magnetic constriction of motor core and torque ripple decrease; the 100Hz noise is further reduced. This technical note presents three solutions for motor operation in AC and DC mode, based on phase control. Motor current and motor efficiency are compared in AC and DC mode. Component selection is proposed for each case, enabling the design of a cost effective solution. AN422 / 02,94 IMPROVED UNIVERSAL MOTOR DRIVE 1 CIRCUIT TOPOLOGIES Three different topologies for control of universal motors are shown in figures 1a, 1b, 1c: - a conventional AC drive using a TRIAC - a DC drive using a TRIAC and a rectifier bridge - a DC drive using an IGBT and a rectifier bridge Each is controlled with a low cost microcontroller, ST6. The difference between the control software concerns the output signal of the microcontroller, which is either adapted to TRIACs or to IGBTs. A and B topologies are operated with a "SNUBBERLESS" TRIAC.
    [Show full text]
  • El/ 010 130 08 a CURRICULUM DEVELOPMENT STUDY of the EFFECTIVENESS of UPGRADING the TECHNICAL SKILLS of EDUCATIONALLY DISADVANTAGED UNION MEMBERS
    R E P O R T R E S U M E S El/ 010 130 08 A CURRICULUM DEVELOPMENT STUDY OF THE EFFECTIVENESS OF UPGRADING THE TECHNICAL SKILLS OF EDUCATIONALLY DISADVANTAGED UNION MEMBERS. BY.. KOPAS, JOSEPH S. NEGRO AMERICAN LABOR COUNCIL REG. IV, CLEVELAND,OHIO REPORT NUMBER BR -6 -1484 PUB DATE 28 NOV 66 GRANT OEG3-0614840601 EDRS PRICE MF40.18 HC33.28 82P. DESCRIPTORS-.. *EDUCATIONALLY DISADVANTAGED, *UNION MEMBERS, *CURRICULUM DEVELOPMENT, *ELECTROMECHANICAL AIDS;TEACHING MACHINES, TEACHING TECHNIQUES, INDUSTRIALEDUCATION, *SKILL DEVELOPMENT: CLEVELAND, OHIO A SECTION OF A JOB TRAINING PROGRAM CONSISTING OFTHIRTY 10 k.HOUR JOB INSTRf.CTION CURRICULUM MODULESWAS DEVELOPED FOR UPDATING AND UPGRADING THE TECHNICAL SKILLS OFELECTRICAL MAINTENANCE EMPLOYEES. THIS JOB TRAINING PROGRAMWAS TRIED OUT IN C(.ASSES CONSISTING OF MAINTENANCEEMPLOYEES OF THE ELECTRICAL DEPARTMENTS IN A STEEL COMPANY.MEMBERS OF THE CLASSES WERE DIVIDED INTO 2 GROUPS OF 20EACH. HALF OF THE TRAINEES IN EACH GROUP WAS LOANED AN ELECTRONICTUTOR TO USE AT HOME. THE OTHER HALF STUDIED TEXTMATERIAL IN A NORMAL WAY WITHOUT ELECTRONIC TUTORS. A TEST WASPREPARED AND USED AS PRETEST AND POST -TEST TO MEASURETHE MASTERY OF THE SUBJECT MATTER COVERED IN THE 30 CURRICULUMUNITS. THE CONCLUSIONS INDICATED THAT TRAINEES WHO HAD ELECTRONICTUTORS ACHIEVED HIGHER ON ALL MEASURES. CRS) -lc/ U. S. DEPARTMENT OF HEALTH,EDUCATION AND Office of Education WELFAR' This documenthas been reproducen person or organa:glon exactly as receivedfrom originating it. Pointsof view Or stated do notnecessarily represent op nio position or policy. official Office ofEducatit.. A Curriculum DevelopmeeStudy of the Effectiveness of Upgrading the Technical Skills of Educationally Disadvantaged Union Members.
    [Show full text]
  • Multiple Choice Practice Questions for ONLINE/OMR AITT-2020 2 Year
    Multiple Choice Practice Questions for ONLINE/OMR AITT-2020 nd 2 Year Electrician Trade Theory DC machine (Generator & Motor) 1 What is the name of the part marked as ‘X’ in DC generator given below? A - Armature core B -Brush C- Commutator raiser D -Commutator segment 2 What is the name of D.C generator given below? A- Differential long shunt compound B- Differential short shunt compound C -Cumulative long shunt compound D -Cumulative short shunt compound 3 Which rule is used to find the direction of induced emf in D.C generator? A- Cork screw rule B -Right hand palm rule C -Fleming’s left-hand rule D -Fleming’s right hand rule 4 Which formula is used to calculate the generated emf in D.C generator? A –ZNPa/60ɸ B -ɸZna/60P C - ɸZnp/60a D - ɸZnp/60 5 What is the formula to calculate back emf of a D.C motor? A -Eb = V/Ia Ra B- Eb = V x Ia Ra C -Eb = V – Ia Ra D -Eb = V + Ia Ra 6 What is the name of the part marked ‘X’ in DC generator given below? A -Pole tip B -Pole coil C -Pole core D -Pole shoe 7 What is the name of the D.C generator given below? A -Shunt generator B -Series generator C- Compound generator D -Separately excited generator 8 Which energy is converted into electrical energy by generator? A -Heat B- Kinetic C -Chemical D -Mechanical 9 What is the name of D.C generator field given below? A -Short shunt compound generator B -Long shunt compound generator C -Differential compound generator D -Cumulative compound generator 10 What is the principle of D.C generator? A -Cork screw rule B -Fleming’s left-hand rule C -Fleming’s
    [Show full text]