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Setting Up a Qualified Electrical Worker Program At Your Facility

OSHA and NFPA talk about setting up a qualified electrical worker program but what exactly does that mean? How do we get there? And what training is needed? TPC Trainco Electrical Instructor Mike Leitzel will guide you through setting up your own QEW program at your facility and answer your questions to keep your employees safe.

Three-Phase Systems

Three-Phase Systems

Covers three-phase motor principles for induction, synchronous, and multi-speed dual-voltage motors. Gives recommended maintenance practices for large AC motors. Covers principles of three-phase motor starters, part winding, reversing, jogging, alternator principles and operation. Describes three-phase power distribution.

TPC Training Systems is authorized by IACET to offer 1.0 CEUs for this program.

Review a full course list for Electrical Systems Technician

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  • Online Course & Test $85.00
  • Course Manual $71.00
  • Course Manual (Spanish) $71.00

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Lesson 1 - Principles of Three-Phase Motors


Induction motors; Squirrel-cage rotors; Pole-phase relationships; Torque, rotor speed, slip, frequency, resistance, reactance, and power factor

Learning Objectives:
– Describe a squirrel-cage rotor.
– List the factors that determine the strength of the magnetic field in an induction motor.
– Discuss pole-phase relationships.
– Demonstrate how to reverse the rotation direction of the magnetic field.
– Discuss the relationship between rotor speed and frequency.

Lesson 2 - Induction Motors


Squirrel-cage motors; Stator and rotor construction; Air gap; Operating features; Wound-rotor motors; Brushes and slip rings; Maintenance

Learning Objectives:
– List the main parts of the stator.
– List operating characteristics of a wound-rotor motor.
– Demonstrate how to check rotor windings for short circuits.
– State the definition of a standard motor.

Lesson 3 - Synchronous Motors


Motor fields, characteristics, and applications; Pull-in torque; Slipping pole; Power factor; Brushless motors; Motor efficiency and care

Learning Objectives:
– List factors that contribute to the torque of an industrial synchronous motor during starting.
– Explain the effects of an amortisseur winding in a synchronous motor.
– State the definition of pull-in torque.
– State the reason why using synchronous motors can increase a low power factor in a plant.
– List the characteristics of brushless synchronous motors.

Lesson 4 - Multispeed Motors


Consequent-pole, constant-horsepower, constant-torque, variable-torque, and dual-voltage motors and connections

Learning Objectives:
– Discuss the operating characteristics of multispeed induction motors.
– Select the best motor for driving equipment that requires the same torque at both high and low speeds.
– State the definition of a variable-torque motor.
– Explain the difference between a constant-horsepower motor and a constant-torque motor.

Lesson 5 - Maintaining Three-Phase Motors


Cleaning; Care of stator and rotor windings; Air gap; Overload and single-phase operation; Motor shaft currents; Bearings; Maintenance schedule

Learning Objectives:
– List the steps in measuring the resistance of the insulation on motor windings.
– Explain how to raise the temperature of a motor winding.
– List the steps in lubricating motor bearings.
– List the conditions that must exist before you can lubricate bearings.

Lesson 6 - Motor Starters


Limitations; Full-voltage and across-the-line starting; Reducing starting current; Primary- and secondary-resistance starters; Maintenance

Learning Objectives:
– Explain how a motor starter works.
– Explain the difference between open transition and closed transition.
– Name the common kinds of reduced-voltage starters.
– List the steps in inspecting motor starters.

Lesson 7 - Three-Phase Motor Controllers


Multiple start-stop controls; Across-the-line reversing starters; Plugging control; Jogging; Controlling surge and backspin

Learning Objectives:
– Explain how to select the best motor starter for a particular application.
– Explain the difference between low-voltage release and low-voltage protection.
– Describe the plugging process.
– Explain how to prevent backspin.

Lesson 8 - Alternators


Characteristics, ratings, and windings; Three-phase alternators; Air gap; Slip rings; Exciters; Voltage regulation; Load characteristics and effects

Learning Objectives:
– Discuss the operating characteristics of alternators.
– List the characteristics that must be considered when you work on alternator windings.
– Name the causes of change in potential difference between terminals as the load changes.
– Demonstrate how to calculate three-phase power in an alternator.

Lesson 9 - Auxiliary Generator Systems


Requirements; Control equipment; Transfer systems; Safety switches; Engine protection; Prime movers and output control; Maintenance

Learning Objectives:
– Explain how an automatic auxiliary generator works.
– List the methods of overcoming voltage-drop problems when starting loads.
– List the parts of a hydraulic starting system.
– State the definition of a prime mover.
– List the four guidelines to follow when troubleshooting or performing routine maintenance on generators.

Lesson 10 - Power Distribution Systems


Distribution voltages; Heat loss; System grounding; Overcurrent protection; Ground relays; Tripping; Network protection

Learning Objectives:
– State the reasons why 240-volt systems are not as widely used as are 480-volt systems.
– Explain the difference between system grounding and equipment grounding.
– List the benefits of system grounding.
– Explain how an overcurrent relay works.
– Name common circuit-opening devices.


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