Lesson 1 - Principles of Alternating Current
Topics:
AC and DC electricity; AC waveform; Peak-to-peak, average, effective values; Energy storage; Faraday's Law; Basic circuit concepts
Learning Objectives:
– State of definition of a waveform.– Demonstrate how to calculate the frequency of an alternator's output.
– Explain how to calculate an effective value.
– Name the kinds of values that must be used when applying the dc rules and laws to ac circuits.
Lesson 2 - Mathematics in AC Circuits
Topics:
Potential difference; Angles and degrees; Vectors applied to AC circuits; Graphic and math solutions; Calculating instantaneous values
Learning Objectives:
– Describe a triangle.– State the definition of a vector.
– Identify the vector representing resistance in a vector diagram.
– Demonstrate how to calculate the total impedance in an ac circuit.
Lesson 3 - Inductance and Inductive Reactance
Topics:
Factors affecting inductance; CEMF; Inductive reactance and time delay; Phase angles; Impedance; Mutual induction; Inductors
Learning Objectives:
– Name the property of a coil that makes it resist changes in current.– List the factors that determine inductance in a coil.
– State the definition of counter electromotive force.
– Demonstrate how to convert a frequency in Hz to a frequency in radians per second.
Lesson 4 - Capacitance and Capacitive Reactance
Topics:
How a capacitor works; Factors controlling capacitance; Kinds of capacitors; Time constants; Capacitive reactance; Phase angle
Learning Objectives:
– Name the parts of a capacitor.– List the factors that affect the amount of charge stored in a capacitor at a given potential difference.
– State the definition of capacitive reactance.
Lesson 5 - Impedance
Topics:
Impedance in series circuits; Phase angles; Resonance in series circuits; Impedance in parallel circuits
Learning Objectives:
– State the definition of impedance– Explain how to calculate the impedance in a series ac circuit.
– Demonstrate how to find the value of a phase angle for a circuit.
– Explain how to calculate the impedance in a parallel circuit.
Lesson 6 - Power and Energy in AC Circuits
Topics:
Work and energy; Power in resistive, inductive, and capacitive circuits; Power factor correction; Power capacitors; Capacitor installation
Learning Objectives:
– State the definition of power.– Demonstrate how to calculate power in an inductive circuit.
– State the reason why capacitors are added to circuits to increase the power factor.
– Explain how to install capacitors correctly.
Lesson 7 - Three-Phase Circuits
Topics:
Three-phase alternators; Y- and delta-connected alternators; Power in three-phase circuits; Load connections; Measuring power
Learning Objectives:
– List the main advantages of the three-phase ac system.– State the definition of phase sequence.
– Demonstrate how to calculate the RMS power in a single-phase circuit.
– Explain how to measure the total power consumed by the load in a three-phase circuit.
Lesson 8 - Principles of Transformers
Topics:
Magnetic field; No-load operation; Transformer construction, losses, and efficiency; Autotransformers; Instrument transformers
Learning Objectives:
– Explain the difference between the primary winding and the secondary winding in a transformer.– Explain how the windings are positioned in a core-type transformer.
– List the kinds of losses that occur in transformers.
– State the definition of a current transformer.
– List the functions of an instrument transformer.
Lesson 9 - Transformer Applications
Topics:
Transformer designation, insulation, cooling, and polarity; Single- and three-phase transformer connections; Installing transformers
Learning Objectives:
– Name general kinds of transformers.– List the temperature limits for each class of transformer insulation.
– Explain how oil-immersed transformers are cooled.
– Name the common methods of connecting three single-phase transformers for three-phase operation.
– Explain how to select the correct location for a transformer.
Lesson 10 - Maintaining Transformers
Topics:
Preventive maintenance; Inspection; Transformer liquids; Transformer failure; Testing; Disassembly and inspection
Learning Objectives:
– Explain what to look for during an inspection of sealed transformers.– List problems that are indicated by an increase in transformer operating temperature.
– Demonstrate how to perform a breakdown test.
– Explain how to locate the exact point of a leak in a welded joint below the liquid level.
– List the steps in inspecting a transformer when a winding fails.
