The Left-Hand Rule
Magnetic Field Around a Coil
Electromagnetic Induction
The Left-Hand Rule for Generators
Basic Motor Operation
Basic DC Motor: Speed Control
Calculating Synchronous Speed
Calculating Running Speed
AC Motor Operation at Over- and Under-Voltages
DC Motor Operation at Over- and Under-Voltages
Minimum Depth of Clear Working Space in Front of Electrical Equipment
Minimum Clearance of Live Parts
Horsepower Ratings for Nema Starters
Maximum Horsepower
Running Overload Units
Motor Branch-Circuit Protective Devices Maximum Rating or Setting
Full-Load Current for Direct-Current Motors in Amperes
Full-Load Current for Single-Phase Alternating Current Motors in Amperes
Three-Phase Alternating Current Motors Full-Load Current
Full-Load Current and Other Data for Three-Phase AC Motors
Motor and Motor Circuit Conductor Protection
General Motor Rules
Motor Branch-Circuit and Feeder Example
General Motor Applications
Maximum Motor Locked-Rotor Current
Maximum Motor Locked-Rotor Current in Amperes, Two & Three Phase, Design B, C, and D
Ohm’s Law
Electrical Formulas for Calculating Amperes, Horsepower, Kilowatts, and kVA
To Find Amperes
To Find Horsepower
To Find Watts
To Find Kilowatts
To Find Kilovolt-Amperes
Kirchhoff’s Laws
To Find Inductance
Inductance (L)
To Find Impedance
Impedance (Z)
To Find Reactance
Reactance (X)
Synchronous Speed
Slip
Locked-Rotor Current Three Phase
Locked-Rotor Current Single Phase
Motor Frames
Frame Dimensions, In Inches
Frame Letter Designations
Insulation Classes
Common Electrical Distribution Systems
Voltage Drop Calculations, Inductance Negligible
Single-Phase Circuits
Three-Phase Circuits
Voltage Drop Calculation Examples
Single-Phase Voltage Drop
Three-Phase Voltage Drop
Maximum Permissible Capacitor KVAR
For Use with Open-Type Three-Phase Sixty-Cycle Induction Motors
Power-Factor Correction
Power Factor and Efficiency Example
Locked-Rotor Code Letters
Single-Phase Motors
Three-Phase Motors
Three-Phase AC Motor Windings and Connections
Nema Enclosure Types Nonhazardous Locations
Nema Enclosure Types Hazardous Locations
U.S. Weights and Measures
Linear Measures
Mile Measurements
Other Linear Measurements
Square Measures
Cubic or Solid Measures
Liquid Measurements
Dry Measures
Weight Measurements (Mass)
Metric System
Prefixes
Linear Measures
Square Measures
Cubic Measures
Measures of Weight
Measures of Capacity
Metric Designator and Trade Sizes
U.S. Weight and Measures/Metric Equivalent Chart
Explanation of Scientific Notation
Useful Conversions/Equivalents
Decimal Equivalents
Single-Phase Motors
Direct-Current Motors
Motor Selection Checklist
Motor Selection Criteria
Typical Load Service Factors
Overcurrent Protection for Two or More Motors
Overcurrent Protection for Motors and Other Loads
Determining Overload Size
Determining Controller Size
Motors 2 Horsepower or Less and 300 Volts or Less
Determining Conductor Sizes for Single-Phase Motors
Determining Conductor Sizes for Adjustable Speed Drives
Motor and Motor-Circuit Conductor Protection
General Motor Rules
Motor Branch Circuit and Feeder Example
General Motor Applications
Approximate Torque Figures, Compound DC Motors
Heater Corrections for Ambient Temperatures
Approximate Torque Figures, AC Motors
Approximate Torque Figures, Wound Rotor Motors
Sizing Load Conductors from Generators
Electrical Safety Definitions
Electrical Safety Checklist
Electrical Safety Lockout–Tagout Procedures
Application of Lockout–Tagout Devices
Removal of Lockout–Tagout Devices
Electrical Safety Shock Protection Boundaries
Electrical Safety How to Read a Warning Label
Pulley Calculations
Determining Belt Length
Horsepower Capacities
Gear Sizing
Determining Shaft Diameter
Gear Reducers
Output Torque
Output Speed
Output Horsepower
Motor Torque
Torque
Starting Torque
Calculating Cost of Operating an Electrical Appliance
Electrical Symbols
Wiring Diagrams
Complete Stop-Start System with Control Transformer
Hand off Automatic Control
Jogging with Control Relay
Wiring Diagrams
Plugging Circuit
Terminal Designations
Generators and Synchronous Motors
Counter-EMF Starting
DC Motors
Two-Speed Starting
Reduced-Voltage Starting
Synchronous Motor
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