Course Objective
This course focuses on the AC induction motor, the most common motor used in industry. Most of the failures of AC motors can be attributed to either improper installation or improper application. Information on the motor nameplate can provide the answer to many of the mechanical drive problems that plague your company.

Benefits
Troubleshoot mechanical drive problems from nameplate data
Improve motor application and maintenance


Outline

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Introduction
Common Electric Motors Used in Industry
Basic Operation of a 3-phase Induction Motor
Components of an AC Induction Motor

Rated Voltage
Rated Voltage vs. System Voltage
Motor Voltage Selection Based on Horsepower Rating
Common Hi/Low Volts Connections
Effects of Variation from Rated Voltage
Unbalanced Voltage Problems

Full Load Amps, Service Factor, and KVA Code
Nameplate vs. Estimated Rating
Service Factor and Allowable Overload Current
Locked-rotor (KVA) Code
High KVA Code and Nuisance Trips

Rated Frequency and Number of Phases
Advantages of Three Phase Motors
U.S. (60 Hz) vs. European (50 Hz) Standards

Rated Full Load Speed (RPM)
Poles, Synchronous Speed and Rotor Slip
Common Multiple Speed Motors and Applications

Proper Motor Application
Horsepower Rating
HP and RPM Limitations
Duty/Time Rating
Starting Torque and the NEMA Design Letter
Efficiency and Power Factor

Environmental Considerations
Enclosure Types Matched to Conditions
Enclosures for Hazardous Locations
Severe Duty Motors
Insulation Class Match to Operating Conditions

Mechanical & Electrical Considerations
NEMA Frame Size Numbers
Frame Number Suffixes and Prefixes
Motor Bearing Numbers Demystified
Common Motor Connection Diagrams