Official Course Description: MCCCD Approval: 07/22/08
ELA257 20052-20086	L+L	2 Credit(s)	4 Period(s)
Industrial Motor Controls
Introduction to motor control, principles of solid-state devices, integrated circuits, electromagnetic motor starters and pilot devices. AC(alternating current) and DC(direct current) motors, electromagnetic control circuits and programmable controllers. Prerequisites: (Registered apprentice status and ELA254) or permission of the apprenticeship coordinator.

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MCCCD Official Course Competencies:
ELA257   20052-20086	Industrial Motor Controls

1.	List specific criteria for selecting a motor controller. (I)
2.	Describe the operation of a diode in a circuit and explain the difference between a zener diode and a junction diode. (II)
3.	Explain the difference between PNP and NPN transistors and between junction transistors and unijunction transistors. (III)
4.	Describe the operation of silicon-controlled rectifiers (SCRs), Diacs and Triacs in AC circuits. (IV)
5.	Explain the principles of operation of manual motor starters and magnetic motor starters. (V)
6.	List the principle uses of magnetic relays and contactors, the advantages of solid-state relays and the basic steps in the operation of common timing relays. (VI)
7.	Describe the purpose of starting motors in sequence and explain the operation of jogging and plugging control circuits for starting and stopping electrical motors. (VII)
8.	Describe the electrical characteristics of DC motors and connect motor leads to form a series, shunt or compound motor. (VIII)
9.	Connect-across-the-line and timed starting controls for DC motors. (IX)
10.	Describe the operation of specific solid-state controls for DC motors. (X)
11.	Describe specific starting methods for AC motors. (XI)
12.	Explain the purpose and function of manual speed control and wound rotor motor application and the process of automatic acceleration. (XII)
13.	State specific advantages of using a magnetic clutch in a drive and describe the operating principles of magnetic clutches and drives. (XIII)
14.	List the five basic gates utilized in digital logic, describe the operation of a start-stop push button control circuit and connect a start-stop push button control using logic gates. (XIV)
15.	List the principle parts of a programmable controller (PC) and describe the operation of the programming terminal, central processor and the I/O track. (XV)

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MCCCD Official Course Outline:
ELA257   20052-20086	Industrial Motor Controls

I. Controller Selection Criteria A. Electrical service 1. AC 2. DC B. Motor C. Operating characteristics D. Operating environment E. Electrical codes and standards 1. National Electrical Code (NEC) 2. OSHA 3. National Electrical Manufacturers Association 4. Underwriters Laboratories II. Diodes A. Circuit operation B. Junction diode C. Zener diode III. Transistors A. PNP B. NPN C. Junction D. Unijunction IV. SCRs - Diacs - Triacs A. SCR 1. AC circuit 2. DC circuit 3. Phase shifting 4. Testing B. Diac C. Triac 1. AC switch 2. AC voltage control 3. Phase shifting 4. Testing V. Motor Starters A. Manual 1. Application 2. Automatic and remote operation 3. Push button line voltage 4. Low voltage protection 5. Thermal overload protection B. Magnetic 1. Starter electromagnets 2. Shaded pole principle 3. Magnet coil 4. Motor overheat 5. Overload protection 6. Ac magnetic starters 7. Ac combination starters 8. Protective enclosures VI. Relays and Contactors A. Control relays B. Contactors 1. Magnetic blowout 2. Mechanically held C. Thermostat relay D. Solid-state relay 1. Advantages 2. Operation E. Timing relays 1. Dashpot 2. Pneumatic 3. Clock 4. Motor-driven 5. Capacitor time limit 6. Electronic VII. Sequence Starting Control A. Automatic sequence control B. Jogging 1. Control relay 2. Control relay on reversing starter 3. Selector switch 4. Push-pull operator 5. Stopping motor C. Plugging 1. Switches and applications 2. Timing relay 3. Alternate circuits 4. Anti-plugging protection 5. Stopping motor VIII. D.C. Motors A. Application - characteristics B. Speed control C. Construction 1. Armature 2. Field windings D. Identifying windings E. Motor types F. Rotation G. Connections H. Applying leads for series, shunt and compound motors IX. Across-The-Line and Timed Starting Controls A. Purpose B. Application X. Solid-State Controls A. Shunt field power supply B. Armature power supply C. Voltage control D. Field failure control E. Current limit F. Speed control XI. Starting AC Motors A. Full voltage B. Primary resistor 1. Reduced voltage 2. Four point C. Autotransformer/compensator D. Impedance E. Star-delta F. Part winding XII. Wound Rotor Motors A. Application B. Manual speed control C. Automatic acceleration 1. Reversing control 2. Frequency relays XIII. Magnetic Clutches and Drives A. Advantages B. Types 1. Single-face 2. Multiple-face C. Magnetic drives XIV. Digital Logic Gates and Start-Stop Push-Button Control A. Logic gates 1. AND 2. OR 3. Invertor 4. NOR 5. NAND B. Start-stop push-button control 1. Operation 2. Connection application XV. Programmable Controllers (PC) A. Basic components 1. Power supply 2. Central processing unit (CPU) 3. Programming terminal 4. Input/output (I/O) track B. Operation 1. Programming terminal 2. CPU 3. I/O track C. Internal relays 1. Counters and timers 2. Off-delay circuit

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