Electrical Control Equipment

This comprehensive award-winning Activ® interactive multimedia training program consists of six individual lessons that train participants to understand the operation and troubleshoot circuit breakers, limit switches, overload relays, motor starters, and electrical control circuits.

Audience: This program is excellent both for the training of electricians and technicians in instrumentation and electronics as well as for the multi-craft training needs of process and manufacturing facilities.

Fuses and Circuit Breakers


Prerequisites: This lesson is designed for participants familiar with AC and DC theory, electrical safety, electrical schematics, and the proper use of hand tools and test instruments.

Description: This lesson describes fuses and circuit breakers, and how they work. This lesson shows and explains maintenance, testing, removing, and installing fuses and circuit breakers. This lesson discusses molded case, multiple, and ground fault circuit breakers.

Objectives:

  • Describe the basic mode of operation of a fuse
  • Identify the specification information
  • Verify that a circuit is de-energized
  • Select the proper replacement fuse and install it
  • Describe the operation of a small, molded case circuit breaker
  • Reset a tripped circuit breaker
  • Explain circuit breaker sensing mechanisms and perform preventative maintenance on a circuit breaker panel
  • Install a circuit breaker and identify one that is a multiple
  • Use a characteristic trip curve to interpret test results
  • Identify and test the operation of a ground fault circuit breaker and install it
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Limit switches


Prerequisites: This lesson is designed for participants familiar with AC and DC theory, electrical safety, electrical schematics, and the proper use of test instruments.

Description: This lesson describes limit switches, how they work, how to recognize them, and typical applications they are used in. This lesson discusses maintenance, troubleshooting, and adjustment requirements for the various limit switches.

Objectives:

  • Use limit switches, including defining the purpose, function, and types of limit switches
  • Explain and visually identify each of the limit switches
  • Describe safety consideration and know how to ensure that a replacement switch will work correctly describe the internal function of a lever-actuated limit switch and its function in a control circuit
  • Maintain, troubleshoot, repair, and adjust a lever-actuated limit switch
  • Describe the internal functions of a photoelectric switch and a proximity switch, and explain how these switches are used in a control circuit
  • Describe the possible malfunctions of these switches
  • Troubleshoot, maintain and repair these switches
  • Explain the internal function of a geared limit switch and torque switch in a control circuit
  • Troubleshoot, maintain and repair these switches
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Switches, Coils, and Overloads


Prerequisites: This lesson is designed for participants familiar with AC and DC theory, electrical safety, electrical print reading, electrical connections, and the proper use of electrical test instruments. An understanding of the operation of control circuits and components, such as switches, relays, fuses, and circuit breakers is recommended.

Description: This lesson describes switches, coils and overloads. This lesson explains the type and operation of switches and overload relays. This lesson covers the testing of switches and coils. Participants will learn the proper way to verify that a circuit is de-energized, and how to determine component malfunctions by use of circuit diagrams, manufacturer’s literature and continuity checks.

Objectives:

  • Explain what types of switches are used in industry and know how to tell if they are functioning properly
  • Know how to test coils and how to test and replace overload relays
  • Explain the concept of poles and throws and describe the operation of momentary and maintained push-button switches
  • Describe how selector switches work
  • Describe rotary switches and explain how to read a switch connection diagram
  • Perform a continuity check on a push-button switch and remove and replace a defective push-button contact block
  • Learn how to check coils for overheating and breaks in the wire winding
  • Explain how an overload relay protects a motor and describe how a bimetallic thermal overload relay works
  • Describe how a melting-alloy thermal overload relay works and explain its heat storage characteristics
  • Describe magnetic and electronic overload relays
  • Describe the common problems of thermal overload relays
  • Install a thermal overload relay in a starter
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Magnetic Starters


Prerequisites: This lesson is designed for participants familiar with AC and DC theory, electrical safety, electrical print reading, electrical connections, and the proper use of electrical test instruments. An understanding of the operation of control circuits and components, such as switches, relays, fuses, and circuit breakers is recommended.

Description: This lesson describes Magnetic Starters. This lesson explains the parts of a magnetic motor starter and its operation. This lesson discusses the correct procedures for troubleshooting a magnetic motor starter. Participants will learn the proper way to determine the malfunction by use of schematic diagrams, manufacturer’s literature, continuity checks, and voltage and resistance tests. This lesson also defines and demonstrates reversing magnetic motor starters.

Objectives:

  • Explain the parts of a magnetic motor starter and its operation, including describing an electromagnet and explaining how the contactor works
  • Identifying troubleshooting steps and performing sensory inspections
  • Performing a test on the armature
  • Executing the disassembly of the motor starter
  • Explaining what an interlock is used for and how mechanical and electrical interlocks work
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Troubleshooting Electrical Control Circuits


Prerequisites: This lesson is designed for participants familiar with AC and DC theory, electrical safety, electrical schematics, and the proper use of electrical test instruments. An understanding of the operation of control circuits and components, such as switches, relays, fuses, circuit breakers, motor starters, contactors, and control transformers is also recommended.

Description: This lesson presents a basic procedure for troubleshooting electrical control circuits. The lesson shows and explains how to gather information about the symptoms, how to verify the symptoms, and how to use the schematic diagram to locate the cause of the problem. The lesson also shows how to perform continuity checks on the circuit and replace any defective components.

Objectives:

  • Develop a logical and systematic strategy for troubleshooting a circuit
  • Obtain all necessary troubleshooting information
  • Verify problem symptoms by performing electrical and/or mechanical operational checks
  • Isolate the problem
  • Replace all defective parts
  • Check the operation of replacement parts
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Inverters: Operation and Maintenance


Prerequisites: This lesson is designed for participants familiar with AC and DC theory, AC motor theory, electrical safety, electrical print reading, and the proper use of electrical test instruments.

Description: This lesson explains the design and operation of inverter drives, and describes control features provided by inverter drive systems. This lesson provides procedures for inspecting and maintaining inverter drives, and gives explanations of common error messages.

Objectives:

  • State the function and parts of inverter drives
  • Describe the principle of operation of pam and pwm inverters
  • Review the operation of a typical induction motor and explain the formula for synchronous speed
  • Explain how to calculate slip percentage and how inverters compensate for slip
  • Describe the three types of inverter drives and describe open-loop and closed-loop control and how flux-vector control drives work
  • Explain how an inverter in a variable-torque application can conserve energy, and how an inverter drive can be used for soft-starting
  • Describe environmental conditions that adversely affect inverter drivers and describe safety precautions for working with drives
  • Give examples of error messages associated with electrical or motor problems
  • Describe a drive overtemperature fault
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