ELT 110: Electric Motor Control

NFPA 70E

1. Describe and demonstrate safety related work practices.
2. Identify and explain importance of personal protective equipment
3. Describe and explain arc flash categories.
4. Describe and explain incident energy.
5. Describe and explain arc flash, limited and restricted approach boundaries.
6. Explain and demonstrate the safety purpose of rubber gloves and protectors.

600 Volt Switching 

1. Explain the meaning of “Normal Operations” and its relation to electrical switching for non-electricians.
2. Identify hazards related to operating electrical equipment and the boundaries imposed and designed to protect non-electricians.
3. Describe site specific policies for notifying emergency response.
4. Apply switching policies to specific site, choose appropriate PPE, and demonstrate proper switching sequence under normal operation.
5. Explain the importance of task training and identify requirements for switch training. 

Meter Safety 

1. Explain the safety specifications and how to operate handheld electronic testers in a safe manner.
2. Demonstrate how to operate handheld electronic testers in a safe manner.
3. Explain how handheld electronic testers and accessories perform basic measurements.
4. Explains and demonstrate how to set a digital multimeter (DMM) to the correct function and range for a given measurement.
5. Demonstrate how to measure a variety of electrical parameters and test electrical components.
6. Determine the proper measurement tool for safe and accurate measurement.
7. Explain the differences between average responding and true-rms measurement on non-linear loads.

Electric Motor Control

Introduction to electric motor control  

 Segment 1- Electrical Safety

1. Explain the importance of the equipment ground connection.
2. Describe the function of five common standards associated with electrical control.
3. Describe ten basic rules of electrical safety.
4. Describe the purpose of the lockout/tagout system used in industry.
5. Perform a lockout/tagout.

Segment 2- Three-Phase Power

1. Describe the operation of 3-phase power.
2. Describe the two most common 3-phase voltage systems.
3. Explain the function of neutral.
4. Use a voltmeter to verify supply voltage.
5. Describe the operation of a grounded and ungrounded system.

 Segment 3- Disconnects and Protective Devices

1. Describe two devices used to disconnect power to a circuit.
2. Use a digital multimeter to check the condition of a fuse.
3. Explain why time-delay fuses are used with motor starting circuits.
4. Describe three important factors to consider with overcurrent protection devices.

Segment 4- Three-Phase Motors

1. Describe the operation of a 3-phase motor.
2. Describe the operating data on a motor's nameplate.
3. Define service factor and explain its importance.
4. Connect a dual-voltage three-phase motor for low voltage operation.
5. Explain why dual-voltage motors should be run on the highest available voltage.
6. Connect a dual-voltage three-phase motor for high voltage operation.

Manual Motor Control and Overload Protections

 Segment 1 – Manual Motor Control

1. Describe five functions of motor control.
2. Describe the four basic requirements of a typical motor installation.
3. Define motor controller and motor starter.
4. Connect and operate a simple motor control circuit

Segment 2 – Manual Motor Starter Operation

1. Describe the functions of two Categories of motor starters.
2. Describe the functions of two types of manual starters.
3. Describe the operation of a manual motor starter.
4. Test the operation of a manual motor starter using a multimeter.
5. Start and stop a motor using a manual starter.
6. Define low-voltage protection and describe its importance.
7. Describe how low-voltage protection is accomplished in a manual starter.
8. Test the low-voltage protection capabilities of a manual starter.

Segment 3 – Overload Protection

1. Describe the function of three types of overloads and give an application of each.
2. Describe the operation of two types of thermal overloads.
3. Describe the operation of a magnetic overload.
4. Set the trip level of a bimetallic overload.
5. Test the operation of a bimetallic overload.
6. Select the correct heaters for a NEMA overload

Control Transformers

 Segment 1 – Introduction to Transformers

1. Describe the operation of a transformer and give its schematic symbol.
2. Define turns ratio and describe how it is calculated.
3. Calculate the turns ratio of a transformer.
4. Describe how the turns ratio determines the secondary voltage of a transformer.
5. Calculate the secondary voltage of a transformer.

Segment 2 – Control Transformer Operation

1. Describe the functions of the four basic components of an electrical control circuit.
2. Describe the function of an electrical schematic diagram.
3. Describe the function of a control transformer.
4. Describe the operation of a control transformer and give its schematic symbol.
5. Connect and operate a control transformer.
6. Describe how to test a transformer.
7. Test a Control Transformer.

Segment 3 – Control Transformer Applications in Machine Control

1. Describe how to size a transformer.
2. Size a control transformer.
3. Describe the operation of a separate control circuit.

Control Ladder Logic

Segment 1 – Electrical Control System Basics

1. Describe the function of three types of electrical control systems and give an application of Each.
2. Describe the three steps of a control process.
3. Describe the function of an indicator lamp and give an application.
4. Describe the operation of a pushbutton switch and give its schematic symbol.
5. Connect and operate a basic electrical control circuit that uses a push button switch.
6. Describe the operation of a selector switch and give its schematic symbol.
7. Connect and operate a basic electric control circuit using a selector switch.

Segment 2 – Ladder Diagram Basics

1. Describe the function of a ladder diagram.
2. Describe the Function of four components of a ladder diagram.
3. Describe six rules of drawing a ladder diagram.
4. Draw a ladder diagram of a control circuit.
5. Describe how to determine the operation of a circuit given a ladder diagram.
6. Determine the operation of a Control circuit given a ladder diagram.
7. Connect and operate a control circuit given a ladder diagram.

Segment 3 – Logic Elements

1. List six elements of control logic.
2. Describe the operation of AND logic and give an application.
3. Connect and operate an AND logic circuit.
4. Describe the operation of OR logic and give an application.
5. Connect and operate an OR logic circuit.

Segment 4 – Logic Elements

1. Describe the operation of NOT logic and give an application.
2. Connect and operate a NOT logic circuit.
3. Describe the operation of NOR logic and give an application.
4. Connect and operate a NOR logic circuit.
5. Describe the operation of NAND logic and give an application.
6. Connect and operate a NAND logic circuit.
7. Design a multiple start/stop pushbutton station control circuit.

Control Relays and Motor Starters

 Segment 1 – Control Relays

1. Describe the function of a control relay and five applications.
2. Describe the operation of a control relay and give its schematic symbol.
3. Describe the operation of two types of control relays and give an application of each.
4. Describe how detached symbology is used to show a control relay on a ladder diagram.
5. Connect and operate a control relay in a circuit.
6. Describe the operation of memory logic and give an application.
7. Connect and operate a memory logic circuit.

Segment 2 – Magnetic Motor Starters

1. Describe the operation of a magnetic motor starter.
2. Identify the basic components of a magnetic motor contactor.
3. Connect and operate a magnetic motor starter connected to a three-phase motor.
4. Describe the operation of a two-wire motor control circuit and give an application.
5. Connect and operate a two-wire motor control circuit

Segment 3 – Two-Wire Control

Segment 4 – Three-Wire Start/Stop Control

1. Describe the operation of a three-wire motor control circuit and give an application.
2. Connect and operate a three-wire motor control circuit.
3. Design a multiple operator station three-wire control circuit.
4. Describe the function of a push-to-test pilot light and give an application.
5. Describe the operation of a push-to-test pilot light and give its schematic symbol.
6. Connect and operate a three-wire control circuit with a push-to-test pilot light.

Introduction to Troubleshooting

  Segment 1 – Introduction to Troubleshooting

1. Describe two levels of troubleshooting and give an application of each.
2. Describe the three methods of testing a component and give an application of each.
3. Describe how to test an indicator lamp.
4. Test an indicator lamp.

 Segment 2 – Control Component Troubleshooting

1. Describe how to test a manual switch.
2. Test a manual switch.
3. Describe how to test a control relay.
4. Test a control relay.

Segment 3 – Motor Starter Troubleshooting

1. Describe how to test a motor contactor.
2. Test a motor contactor.
3. Describe how to test an overload relay.
4. Test an overload relay.

Segment 4 – Power Component Troubleshooting

1. Describe how to test the windings of a 3-phase motor with a digital multimeter.
2. Test the windings of a 3-phase motor with a digital multimeter.
3. Test the windings of a control transformer with a digital multimeter.