adventures in electrical engineering or how i spent my summer vacation thomas reed poteet high...

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Adventure s in Electrica l Engineeri ng Or How I Spent My Summer Vacation Thomas Reed Poteet High School E 3 Summer Research Program At Texas A&M Adventure s in Electrica l Engineeri ng Or How I Spent My Summer Vacation Adventure s in Electrica l Engineeri ng

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Page 1: Adventures in Electrical Engineering Or How I Spent My Summer Vacation Thomas Reed Poteet High School E 3 Summer Research Program At Texas A&M Adventures

Adventures in

Electrical Engineeri

ng

Or

How I Spent My Summer

Vacation

Thomas ReedPoteet High SchoolE3 Summer Research Program

At Texas A&M

Adventures in

Electrical Engineeri

ng

Or

How I Spent My Summer Vacation

Adventures in

Electrical Engineeri

ng

Page 3: Adventures in Electrical Engineering Or How I Spent My Summer Vacation Thomas Reed Poteet High School E 3 Summer Research Program At Texas A&M Adventures

Short-Term Monitoring ExperimentsComplete Setup Diagram

Substation

Feeder(7200 V)

Feeders

Cable Lateral

Analog SignalConditioning Unit

Digital Computer(Data Acquisition

System)

Phase CurrentNeutral Current

OutputSignals

MeasurementUnits

Loads

DistributionTransformer

7200:120/240 V

Phase Voltage

Page 4: Adventures in Electrical Engineering Or How I Spent My Summer Vacation Thomas Reed Poteet High School E 3 Summer Research Program At Texas A&M Adventures

Signal Measurement Units Two clamp-on current transducers (Pearson Electronics, Inc.). Ratio = 0.1 V/A. Connected to the primary side of the transformer.

Voltage measurement from secondary side.

Phase Current

Neutral Current

Pad Mounted Transformer

Primary Side

Secondary Side

Online, non-destructive

Page 5: Adventures in Electrical Engineering Or How I Spent My Summer Vacation Thomas Reed Poteet High School E 3 Summer Research Program At Texas A&M Adventures

Project on Electricity

“What is Going On?”

Page 6: Adventures in Electrical Engineering Or How I Spent My Summer Vacation Thomas Reed Poteet High School E 3 Summer Research Program At Texas A&M Adventures

Explanation of Project

Through a series of experiments with circuits, building different types circuits using batteries and resistors, and collecting and analyzing data, students will discover relationships between voltage, current and resistance. Also, they will look at what effect power has on the system and do analysis on current and power usage.

Page 7: Adventures in Electrical Engineering Or How I Spent My Summer Vacation Thomas Reed Poteet High School E 3 Summer Research Program At Texas A&M Adventures

Phase 1 of Project

• Students, in groups of two, are to “build” the required circuits, using up to four size D batteries (1.5v) and different size resistors.

• They will examine simple circuits and circuits in series and in parallel, and determine relationships and write equations.

Page 8: Adventures in Electrical Engineering Or How I Spent My Summer Vacation Thomas Reed Poteet High School E 3 Summer Research Program At Texas A&M Adventures

Phase 2 of Project

• Students will be introduced to Power and its relationship to voltage, current and resistance.

• Students will then look at the power usage in their own homes and determine power and current usages for several scenarios and design a room around current and power usage.

Page 9: Adventures in Electrical Engineering Or How I Spent My Summer Vacation Thomas Reed Poteet High School E 3 Summer Research Program At Texas A&M Adventures

Phase 1Circuit Builders Project

Page 10: Adventures in Electrical Engineering Or How I Spent My Summer Vacation Thomas Reed Poteet High School E 3 Summer Research Program At Texas A&M Adventures

What is Happening? Experiment procedure: Start with one battery in holder. Attach clips to the ends of the resistor attach clips to battery pack. Take volts reading. Record data. Take amp reading. Record data. Detach clips from battery pack. Insert another battery into battery pack. Repeat procedure until done with all four batteries. When doing resistors in series or parallel attach resistors in proper sequence before attaching to battery. Repeat procedure as before.

Procedures document. Along with this page, students are given directions on how to set up circuits.

All the worksheet can be accessed by double clicking the Word Document Icon in PowerPoints edit mode.

Microsoft Word Document

Page 11: Adventures in Electrical Engineering Or How I Spent My Summer Vacation Thomas Reed Poteet High School E 3 Summer Research Program At Texas A&M Adventures

Experiment 1. lab report Using a 100 resistor and four 1.50v batteries (size D) Set up circuit and collect data for each set of batteries. Enter appropriate data in table V I Graph Data I is the current in amperes. V is the voltage in volts. R is the resistance in ohms. What is the relationship between the amps and the volts? What is the effect of the resistor (100 ) on this relationship? Write an equation that fits the data.

Current in amps (I)

Volts (V)

This is the initial experiment to get the project running. Helping either whole class or with the groups, students are carefully monitored to insure desired outcomes.

Page 12: Adventures in Electrical Engineering Or How I Spent My Summer Vacation Thomas Reed Poteet High School E 3 Summer Research Program At Texas A&M Adventures

Experiment 2. lab report a) Using a 50 resistor and four 1.5 v batteries (size D) Set up circuit and collect data for each set of batteries. Enter appropriate data in table. V I Graph the Data I is the current in amperes. V is the voltage in volts. R is the resistance in ohms. What is the relationship between the amps and the volts? What is the effect of the resistor (50 ) on this relationship? Write an equation that fits the data.

Current in amps (I)

Volts (V)

This experiment is to have data to compare with the first so the students will have more than one example to draw from when they are writing the general equation.

Page 13: Adventures in Electrical Engineering Or How I Spent My Summer Vacation Thomas Reed Poteet High School E 3 Summer Research Program At Texas A&M Adventures

In this portion of the project they are to derive the general equation V=IR, or variant, from previous experiments and are to verify their findings in another experiment.

Experiment 2. Page 2 From the two experiments, can you generalize the relationship using the variables for voltage (V), current (I), and resistance (R)? Experiment 2 (using equation developed) b) Predict the current in amps (I) using the four voltages and a 10 resistor. V I 1.5 3 4.5 6 Run experiment using a 10 W resistor to confirm predictions. V I Does the data collected agree with the predicted data? (Here you should put the voltage found into the equation developed.) Does the general equation hold up for this situation?

Page 14: Adventures in Electrical Engineering Or How I Spent My Summer Vacation Thomas Reed Poteet High School E 3 Summer Research Program At Texas A&M Adventures

Experiment 3 a) Using two 50 resistors, run the experiment.

Set up circuit, resistors in series, and collect data for each set of batteries. Enter appropriate data in table.

V I

Graph the Data Use the appropriate variables.

How do these numbers compare to the first experiment? How does the resistance of the two resistors compare to the total resistance? Is there a formula for finding the resistance in a series? If so, what is it?

Current in amps (I)

Volts (V)

Here students will begin to understand what happens when resistors are put into series.

Page 15: Adventures in Electrical Engineering Or How I Spent My Summer Vacation Thomas Reed Poteet High School E 3 Summer Research Program At Texas A&M Adventures

Experiment 3 b) Run experiment using five (5) 10 resistors.

Set up circuit and collect data for each set of batteries. Enter appropriate data in table. Graph the data. V I How do these numbers compare to the second experiment? Does this agree with what happened in experiment 3a? If you have three resistors, R1, R2, & R3, how do you find the resistant of the circuit, RT?

Current in amps (I)

Volts (V)

Now students will verify previous findings and write a generalized equation for a general series.

Page 16: Adventures in Electrical Engineering Or How I Spent My Summer Vacation Thomas Reed Poteet High School E 3 Summer Research Program At Texas A&M Adventures

Experiment 4 a) Run experiment using two (2) 100 resistors.

Set up circuit and collect data for each set of batteries. Enter appropriate data in table. Graph the data. V I How do these numbers compare to the other experiments? What could be happening with the resistors and the total resistance?

Current in amps (I)

Volts (V)

Students explore resistors in parallel. In groups, students collect data. As whole class, discuss outcomes and relate to previous experiments and aide students in finding correct relationship.

Page 17: Adventures in Electrical Engineering Or How I Spent My Summer Vacation Thomas Reed Poteet High School E 3 Summer Research Program At Texas A&M Adventures

Experiment 4 b) Run experiment using two (2) 50 resistors.

Set up circuit and collect data for each set of batteries. Enter appropriate data in table. Graph the data. V I How do these numbers compare to the other experiments? What could be happening with the resistors and the total resistance?

From the collected data, can you determine the relationship between the resistors

in parallel and the total resistance? Is there an equation? If so, what is it?

Current in amps (I)

Volts (V)

Here students explore parallel resistors again. They collect data and determine formula for the resistance of the circuit with aide of teacher in whole class discussion.

Page 18: Adventures in Electrical Engineering Or How I Spent My Summer Vacation Thomas Reed Poteet High School E 3 Summer Research Program At Texas A&M Adventures

Phase 2Home Project

Page 19: Adventures in Electrical Engineering Or How I Spent My Summer Vacation Thomas Reed Poteet High School E 3 Summer Research Program At Texas A&M Adventures

In this Phase of the project, students take a

look at POWER. They are given the power equation, P= VI & P=I2R, and are to find for missing value in several situations.

Phase 2

POWER P=VI and P=I2R are the equations for power (wattage used) If you are given the wattage of a device, knowing the voltage, you can determine the resistance and the current used. Using substitution and the numbers from fist experiment, determine the wattage (W) used by the circuit. How can you determine the current (amps) used in an electrical device if you are only given its wattage (remember that most household outlets have 120v)? How much current (amps) does a sound system rated at 100 watts use? How much resistance (ohms) does a sound system rated at 100 watts use? How much power (watts) does a device with a current of .5A use? A typical light bulb draws 75 watts, how much current (amps) does it draw? What is its resistance?

Page 20: Adventures in Electrical Engineering Or How I Spent My Summer Vacation Thomas Reed Poteet High School E 3 Summer Research Program At Texas A&M Adventures

Phase 2 Project Part 1 In your home, select a room. Find the wattage of all electrical devices being used in that room. List items and their wattages, and give total wattage. Determine the current (amps) required to run those devices, individually and collectively. List items and their current (amps) demands, give total amps required for room.

In this section of the project, the students are to look at the power usage in their homes.

Page 21: Adventures in Electrical Engineering Or How I Spent My Summer Vacation Thomas Reed Poteet High School E 3 Summer Research Program At Texas A&M Adventures

Phase 2 Part 2 In your home, what room is most likely to throw a circuit breaker? Determine the power usage for each electrical device in the room and the current required for each. List items and their wattage and current demands. Find the power usage for the whole room if everything was plugged in and on. Find the current demand for the room. What size circuit breaker does the room use?

Phase 2 Part 2, page 2 Find the combination of the MOST number of items that can be on before the circuit breaker is tripped. List the items and their wattage and current demands. Find the combination of the LEAST number of items that can be on before the circuit breaker is tripped. List the items and their wattage and current demands.

In this part, students are to find out power demands and current requirements for the room the trips its circuit breaker most often. They are to determine the maximum and minimum number of items that can be plugged in and turned on without tripping the breaker.

Page 22: Adventures in Electrical Engineering Or How I Spent My Summer Vacation Thomas Reed Poteet High School E 3 Summer Research Program At Texas A&M Adventures

Phase 2 Part 3 In this portion of the project, you are to design a power/current

model for a room. You are to design the room around required

electrical items, plus any other items you wish to add to the room.

You decide what size and how many circuit breakers are needed for

the room. You must first find out the power usage for each electrical

item and its current draw (amps needed). Then you decide what size

circuit breaker and how many you would need to cover the room. In

this room you must have these items, you may have more, but the

following are required; a computer work station, including

monitor, cpu, and a printer, an entertainment center, including a

TV, a VCR and/or DVD player, a game station of some kind, and a

sound system of some kind, two light sources, and a clock or

clock radio. You are to list each item, giving the brand name, its

wattage and calculate its current need. On deciding what size breaker

to use, realize the larger the breaker, the higher the chance for over

heating the power lines in the walls. The largest size breaker should

be a 20A breaker; you may use 10A and/or 30A breakers as well.

This is the final stage of the unit. The students design the electrical usage of a room and decide on number and type of breakers needed.