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Basics of Electricity
Learning Skills
Diagramming, Selecting Tools, Interpreting
Why?
Everyone in society should have some basic knowledge about electricity which directly affects their
daily decisions concerning its use. The ramifications of other knowledge in SMART GRID are built
upon basic principles of Electricity. Electricity, as safe as we have tried to make it, causes many injuries and deaths annually, most often when users take it lightly or misunderstand how it works and can
be used safely. Therefore, increasing your understanding of the nature of the electricity will help to
improve your ability to use and work with it safely.
Learning Objectives
This learning activity will teach you to:
1. Comprehend the fundamental principles of electricity and of electric current
2. Measure electricity and analyze the circuits
3. Increase safety awareness in the use of electricity
Performance Criteria
Successfully completion of this activity means that you will be able to:
Analyze a typical standard circuit within a home in order to troubleshoot it
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Measure, describe, and explain the changes in voltage and current in an electrical circuit
Clarify what causes reliability deterioration
Understand safety issues
Understand the difference between electrical power and energy as applied to household
appliances
Terminology
ammeter
circuit efficiency
electrical resistance
electricity
power
voltage
electrical current
electrical loss
energy
energy meter
voltmeter
wattmeter
continued on following page
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Models
Water-electrical circuit analogy
Available as an interactive exploration model at:
http://hyperphysics.phy-astr.gsu.edu/hbase/electric/watcir.html
Resources
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http://www.allaboutcircuits.com/vol_1/index.html
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http://www.allaboutcircuits.com/vol_2/index.html
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http://hyperphysics.phy-astr.gsu.edu/hbase/electric/watcir.html
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Online Circuit modeling software
http://phet.colorado.edu/en/simulation/circuit-construction-kit-ac
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Energy meter
http://www.merrillan.net/utilities/documents/Understanding_Your_Electric_Meter.pdf
Plan
1. Read the first five chapters of All About Circuits (Vol 1): http://www.allaboutcircuits.com/vol_1/
index.html (You should strongly consider using a Reading Log to help with the readings in this
activity.)
2. Read chapter 8 of All About Circuits (Vol 1): http://www.allaboutcircuits.com/vol_1/index.html
3. Read chapter 1 of All About Circuits (Vol 2): http://www.allaboutcircuits.com/vol_2/index.html
4. Note that All About Circuits (Vol 1 & 2) use spice software for electric circuit simulation. Instead
of spice, you will use the Online Circuit modeling software available at:
http://phet.colorado.edu/en/simulation/circuit-construction-kit-ac
5. Answer the Critical Thinking Questions.
6. Complete the Skill Exercise.
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Critical Thinking Questions
1. What’s the difference between static and dynamic electricity?
2. What are the fundamental principles of electricity?
3. How would you explain electricity concepts using analogies with water flow?
4. What are the components in a standard circuit?
5. What is the measurement of electricity and tools used for this measurement?
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6. How are voltage and current related in a circuit?
7. In analyzing a circuit, what do you need to look at in order to explain what is going on?
8. What are the key purposes for circuit breakers, fuses, and other protective devices?
Skill Exercises
• Analyze a simple DC circuit consisting of source and a resistor. Calculate the voltage across the
resistor, the current through the resistor, and the power/energy consumed in the resistor load.
• Use the online circuit modeling software to simulate the proposed circuit and compare your
calculated results with the simulation results.
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