Electrical and Electronics: Module 3

Module 3A: Electrical Principles of Alternating Current Circuits and Transformers (Core)

Suggested time: 5 - 8 hours

Level: Intermediate

Prerequisites: Module 1, 2

Foundational Objectives

To use appropriate terminology for electricity or electronics in context.
To demonstrate the safe use and knowledge of meters and hand and power tools used in the electrical industry.
To be knowledgeable about the different materials and devices and their application in the electrical field.

Common Essential Learnings Foundational Objectives

Note: Other CELs may be emphasized.

Learning Objectives	Notes
ALTERNATING CURRENT (AC)

3.1 To define alternating current (AC). (CCT)	Discuss with students the various AC sources.
3.2 To explain the difference between alternating current (AC) and direct current (DC). (COM)	Students may draw common AC and DC wave forms.
3.3 To define values related to current or voltage on a given sine wave. (IL, NUM)	With the help of an oscilloscope, students will determine values of a given sine wave, peak (pk), peak to peak (pk to pk), Root Mean Square (RMS).
3.4 To define terms that are related to a sine wave. (COM)	Students should observe a sine wave and label the different parts (cycle, alternations, period and frequency).
3.5 To explain the advantages of using AC.	Students may research areas where AC is being used and explain why. Discuss the generator principle. The history of the competition between supporters of DC and AC in the early days of electrical utilities is very interesting. It could be an opportunity for student research.

Module 3B: Electrical Principles of Alternating Current Circuits and Transformers (Core)

Suggested time: 5 - 8 hours Level: Advanced

Prerequisites: Modules 1, 2

Learning Objectives	Notes
BASIC TRANSFORMERS
3.6 To understand the operation of a transformer.	Describe and discuss the electrical properties of induction. Explain basic transformer action. Construct a simple transformer.
3.7 Identify different types of transformers. (IL, CCT)	Student should identify different transformers (i.e., step-up, step-down, isolation transformers) and explain where they would be used. Students may list several uses for transformers.
3.8 Explain the turns ratio and its effect on voltage and current. (NUM)	Students use the basic turns ratio formula to calculate current and voltage. When: Np is the number of turns in the primary winding Ns is the number of turns in the secondary winding Vp is the voltage in the primary winding Vs is the voltage in the secondary winding Is is the current in the secondary winding Ip is the current in the primary winding