E I Z I R - SaskPower 2 Study Guide.pdffeeds a series street lighting circuit of fifty lamps when...

EI R

EI Z

Written by:

Ted Elliott

Edited by:

Earl Robillard

Published and Illustrated by:

Ted Elliott

Karen Becker

TABLE OF CONTENTS

INTRODUCTION .......................................................................... iv D. C. REVIEW - SERIES CIRCUITS ..........................................1 - 3 D. C. REVIEW - PARALLEL CIRCUITS..................................... 2 - 3 D. C. REVIEW - POWER AND ENERGY .................................... 3 - 3 TWO-WIRE CIRCUITS REVIEW ............................................... 4 - 3 GROUNDING AND BONDING REVIEW ..................................... 5 - 3 VECTOR REVIEW .................................................................. 6 - 3 BLOCK AND TACKLE REVIEW ............................................... 7 - 3 MAPS AND SURVEY REVIEW ................................................. 8 - 3 STUDY GUIDE ANSWER SECTION .......................................... 9 - 3

The following Study Guide was initiated with the students' best interests in mind and is designed to better prepare the student for upcoming qualification training. A constant proven fact is that students who come to class well prepared tend to learn the new course material with relative ease, while those who do not often have problems.

When a student line person comes to class with no preparation prior to his/her arrival, the instructors have the following two options:

1. We can pace our lessons based on the student who has not prepared, thereby risking complete coverage of the course material and making it unfair to those students who have prepared.

2. We can pace our lessons based on the students who have prepared and, in doing so, risk losing those who have not.

We, as Instructors, are not comfortable with either option, hence, the following Study Guide is being introduced to overcome this dilemma.

The SaskPower Training Center is a modern, well equipped building with the facilities and staff that apprentices require to learn their trade. Students must come prepared to provide the hard work and study required. Any student who is not prepared to come to the Training Center with this commitment in mind may wish to reconsider his or her choice of careers. There are a great many others who would be willing to make this commitment and are eager to have the same opportunity.

All students should complete the following assignments as they will help to prepare them for the next step of their qualification training. Should anyone require assistance in completing this Study Guide, please consult supervisors, peers, or the instructors in Weyburn.

We stress that this material must be completed by each student before attending the next level of training and no excuses will be tolerated. Failure to complete the Study Guide may result in postponement of an apprentice's training until sufficient preparation has been made.

We look forward to seeing you. Good luck!

INTRODUCTION

D. C. Review - Series Circuits

1 - 2


1. If electrons travel freely through a material, that material is said to be

a) an insulator

b) stable

c) a conductor

d) none of these

2. If few electrons can travel through a material, that material is said to be

a) an insulator

b) unstable

c) a conductor

d) none of these

3. There is no such thing as a perfect insulator.

a) True

b) False

D. C. REVIEW - SERIES CIRCUITS

1 - 3


4. The opposition to current flow through a material is called

a) Voltage

b) amperage

c) resistance

d) none of these

5. Ohms are a unit of measure of

a) voltage

b) current

c) resistance

d) all of these

6. Electric current can be defined as the definite drift of electrons from a point of negative potential to a

a) point of negative potential

b) point of neutral potential

c) point of positive potential

d) none of these

7. The unit of measurement of electromotive force is the

a) ampere

b) volt

c) ohm

1 - 4


d) degree

8. Current flowing through a resistance produces

a) voltage

b) ohms

c) current

d) heat

9. Number 10 copper wire has a resistance of about 1 ohm per 1,000 feet and aluminum wire the same size has a resistance of about 1.7 ohms per 1,000 feet, therefore, copper wire has about

a) twice as much resistance

b) half as much resistance

c) one fourth as much resistance

d) the same resistance

10. The ampere is the unit of measure of

a) flow of electric current

b) voltage

c) resistance

d) temperature

11. Match the following with the proper symbol

1 - 5


a) amperes I

b) current E

c) voltage R

12. Voltage, EMF, Potential Difference, potential and electromotive force are all terms used to define

a) electrical pressure

b) current flow

c) electrical resistance

d) none of these

13. Mark all of the following which must be considered in every electric circuit

a) voltage

b) current

c) resistance

d) none of these

14. Ohm's Law expresses the relationship that exists between

a) voltage and current

b) voltage and resistance

c) current and resistance

d) voltage, current and resistance

1 - 6


15. What letter symbols mean the same as the following words or terms?

a) voltage

b) current

c) resistance

16. What opposes current flow in a circuit?

a) resistance

b) volts

c) amperes

d) potential difference

17. In order for a current to flow through a resistor what must be applied to the resistor?

a) resistance

b) voltage

c) amperes

d) ohms

18. Ohm's Law is written I = E/R. Check other correct ways it is usually written

a) I = RE

b) E = IR

c) R = IE

1 - 7


d) R = E/I

1 - 8


19. A heating element has a resistance of 20 ohms. When connected to a 120 volt circuit how much current will flow? (Show all work)

a) 60 amperes

b) 10 amperes

c) 1/6 of an ampere

d) 6 amperes

20. The resistance of an incandescent lamp that operates on 120 volts and draws a current of 2.5 amps is (show all work)

a) 4.8 ohms

b) 300 ohms

c) 38 ohms

d) 48 ohms

21. One tenth to two tenths of an amp is a dangerous and sometimes fatal amount of current to pass through the human body. If the resistance of the body is 15,000 ohms and it should touch a conductor energized at 2,300 volts, how much current could flow? (show all work)

a) .153 amps

b) 23 amps

c) 15 amps

d) none of these

1 - 9


22. In question 21 above, the amount of current

a) could be fatal

b) definitely is not dangerous

c) is not important

d) is not harmful to the body

23. What is the voltage drop in 1,000 feet of No. 2 AWG copper wire, the resistance of which is .1563 ohms, when 90 amps flow through it? (Show work)

a) 90 volts

b) 1563 volts

c) 14.067 volts

d) 140,67 volts

24. Ohm's Law is expressed as an equation using E, I and R. When two of these values are known, the third value

a) cannot be found

b) can be calculated

c) is not important

d) can be found

1 - 10


25. When the voltage remains fixed, an increase in resistance will result in:

a) no change in current flow

b) an increase in current flow

c) a decrease in current flow

d) none of these

26. To increase the current in a circuit you would increase the resistance.

a) True

b) False

27. What is the resistance of a series street lamp when the current through it is 6.6 amps and the voltage drop across it is 48.4 volts? (show all work)

a) 501.84 ohms

b) 354.772 ohms

c) 15.501 ohms

d) 7.33 ohms

28. What is the voltage required to force 7.5 amperes through a resistance of 32 ohms? (Show all work)

a) 40 volts

b) 4 volts

c) 240 volts

1 - 11


d) 80 volts

1 - 12


29. Resistance is measured in ohms and opposes the flow of current.

a) True

b) False

30. How many amperes will flow in a heater that has a resistance of 32 ohms and is connected to a 480 volt source? (Show all work)

a) 153.60 amperes

b) 720 amperes

c) 15.36 amperes

d) 15 amperes

31. A circuit that has only one path in which the electrons flow is called a

a) parallel circuit

b) series circuit

c) parallel-series circuit

d) short circuit

32. Draw a circuit showing three resistors in series and connected to battery.

1 - 13


33. The line current in a series circuit is equal to the current in any part of the circuit.

a) True

b) False

34. The line current in a series circuit is equal to the sum of the currents in the individual resistors.

a) True

b) False

35. What is the value of the current leaving a transformer which feeds a series street lighting circuit of fifty lamps when the current through one lamp is 6.6 amps?

a) 330 amps

b) 6.-6 amps

c) .132 amps

d) none of these

36. The formula for determining the source or supply voltage in a series circuit is

a) It = Il = I2 + I3

b) Rt = Rl + R2 + R3

c) Eapp = El + E2 + E3

d) none of these

1 - 14


37. The formula for determining the total or equivalent resistance in a series circuit is

a) It = II + I2 + I3

b) Rt = Rl + R2 + R3

c) ES + El + E2 + E3

d) none of these

38. What total current will flow in two 40 watt, 120 volt lamps, connected in series, used as a test light to check 240 volt circuits, if each lamp has a resistance of 360 ohms? (Show all work)

a) .333 amps

b) 3.77 amps

c) 1/2 amp

d) 2 amps

39. What current will flow in a circuit when resistors of 4 ohms, 13 ohms and 23 ohms are connected in series with an applied voltage of 240 volts? (Show all work)

a) .6 amps

b) 1.6 amps

c) 6 amps

d) 16 amps

1 - 15


40. Four Resistors are connected in series. They have the following values:

R1 = 15 ohms, R2 = 40 ohms, R3= 60 ohms, R4=100 ohms.

The current through the circuit is 2 amps.

a) Draw a diagram of the circuit.

b) Find and show on the diagram the voltage drop across each resistor.

c) Find and show the voltage applied to this circuit (source voltage).

41. #10 copper has a resistance of 10 per 1000'. A motor which is 200' away from a 120 volt source draws 14 amps and is fed by #10 copper conductor. What is the voltage measured at the motor?

1 - 16

D. C. Review Parallel Circuits

2 - 2


1. How does the total or equivalent resistance of a group of resistances connected in parallel compare with the resistance in any branch?

a) they are equal

b) total resistance is always less

c) total resistance is always more

2. Adding a resistance in parallel will increase the total (Line) current.

a) True

b) False

3. What effect will adding a resistance in parallel have upon the total current?

a) increases current

b) decreases current

c) current remains the same

d) none of these

D. C. REVIEW - PARALLEL CIRCUITS

2 - 3


4. What effect will adding a resistance in parallel have upon the total or equivalent resistance?

a) resistance increases

b) resistance decreases

c) resistance remains the same

d) none of these

5. What is the total resistance of 20 street lamps connected in parallel if each lamp has a resistance of 40 ohms?

a) 1/2 ohm

b) 1 ohm

c) 2 ohms

d) 4 ohms

6. Find the total resistance of the following three resistances connected in parallel:

Rl = 12 ohms, R2 = 20 ohms, and R3 = 30 ohms.

2 - 4


7. Three resistances of 15, 60, and 90 ohms are connected in parallel. What is their total resistance?

8. What is the total resistance of 4 heaters connected in parallel if each heater has a resistance of 12 ohms?

a) 1/12 ohm

b) 2 ohms

c) 3 ohms

d) 12 ohms

9. A 12 ohm heater is added in parallel to a 20 ohm heater which is used to heat a room. What is the total resistance?

2 - 5


Answer questions 10, 11 and 12 from the following statement:

A 12 ohm heater is added in parallel to another 12 ohm heater which is used to heat a room.

10. The heat in the room will be

a) increased

b) decreased

c) unchanged

11. The total resistance of the circuit will be

a) increased

b) decreased

c) unchanged

12. The current flowing in the circuit will be

a) increased

b) decreased

c) unchanged

13. You can increase the heat in a room by adding another electric heater in parallel to the one already connected to the circuit and by so doing you decrease the total resistance and permit more current to flow.

a) True

2 - 6


b) False

14. When you plug a lamp into a receptacle in a house you are connecting it in series with the other lamps in the house.

a) True

b) False

15. For a ground system to be effective it should have the lowest resistance value possible. Each time a ground rod is driven and connected to a common neutral you are adding a resistance in parallel. If there are 250 such grounds on a distribution line, each with 20 ohms resistance, what is the total resistance of the system?

2 - 7


Answer questions 16 and 17 from the following statement:

Bundled or multiple conductors are sometimes used for each phase of a transmission line.

16. When conductors are bundled you are adding resistances in

a) series

b) parallel

c) none of these

17. When conductors are bundled the total resistance is

a) increased

b) decreased

c) unchanged

18. What voltage is required to send 10 amps through a parallel connection of four 48 ohm lamps?

a) 10 volts

b) 12 volts

c) 48 volts

d) 120 volts

2 - 8


Answer questions 19, 20 and 21 from the following statement:

An electric heater has a 30 ohm and a 20 ohm element connected in parallel and supplied by 120 volt source.

19. What is the total resistance?

a) 10 ohms

b) 12 ohms

c) 50 ohms

d) 600 ohms

20. What is the total current?

a) 10 amps

b) 12 amps

c) 120 amps

d) 600 amps

21. What current flows through the 20 ohm element?

a) 6 amps

b) 10 amps

c) 12 amps

d) 120 amps

2 - 9


Answer questions 22, 23 and 24 from the drawing below.

120Vdc

A

A

A

24ohms 12ohms

I=18Amps

R1 R2 R3

22. What current flows through Rl?

a) .2 amps

b) 3 amps

c) 5 amps

d) 10 amps

23. What current flows through R2?

a) .2 amps

b) 3 amps

c) 5 amps

d) 10 amps

2 - 10


24. What current flows through R3?

a) .2 amps

b) 3 amps

c) 5 amps

d) 10 amps

25. The total current in a parallel circuit is the sum of the currents through the individual branches.

a) True

b) False

Answer questions 26, 27, 28 and 29 from the drawing below.

120Vdc 12ohmsR1 R2 R3

20ohms6ohms

26. The total current of the circuit is

a) 10 amps

b) 20 amps

c) 36 amps

d) 120 amps

2 - 11


27. What is the total resistance of the circuit?

a) 3.33 ohms

b) 36 ohms

c) 38 ohms

d) 60 ohms

28. The total current that flows is

a) 3.33 amps

b) 10 amps

c) 30 amps

d) 36 amps

29. The larger current flows through the branch that has the resistance which is

a) largest

b) smallest

c) intermediate

d) none of these

2 - 12


30. Each time that you connect a lamp in parallel or multiple to a street lighting circuit and you increase the total current this means that the total resistance has been

a) increased

b) decreased

c) unchanged

d) none of these

31. The currents through the branches of a parallel circuit are not necessarily the same.

a) True

b) False

32. The voltage drop across each resistance of a group of resistances connected in parallel are the same.

a) True

b) False

33. A group of eight Christmas tree lights draws .75 amps when connected in series across a 120 volt source. What is the resistance of each lamp?

2 - 13


34. Calculate the current flow in the following circuit.

120Vdc

AA

R1 R2 R310ohms

4amps4amps

35. A 10 ohm resistor and a resistor of unknown value are in series across a 120 volt supply. The current flow is 3 amps. The voltage drop across the unknown resistor is 90 volts. What is the voltage drop across the 10 ohm resistor? Calculate the value of the unknown resistor by two methods.

2 - 14


36. Three resistors in series across a 120 volt source draw a current of 1.5 amps.

R 1 = 12 ohms

R 2 = 14 ohms.

a) What is the value of R 3 ?

b) What is the voltage drop across each of the resistors?

37. Calculate the individual branch currents and the line current in the following circuit.

R1 R2 R3116Vdc 10ohms 29ohms 20ohms

A

A

A A

2 - 15


38. Four lamps of equal size draw a line current of 12 amps when placed in parallel across a 120 volt supply. What is the resistance of each resistor?

39. Two lamps are connected in parallel. The voltage across each of the lamps is measured at 120 volts. What is the line voltage?

2 - 16


40. Solve for the value of R2 in the following circuit:

R1 R2 R3

A

A

9amps

60ohms

3amps

120Vdc

41. Solve for the line current in the following circuit:

R1 R2 R3

A 4.5amps

26ohms 20ohms 13ohmsVdc

2 - 17


2 - 18

D. C. Review Power and Energy

3 - 2


1. In an electric circuit, power is the rate of doing electrical work in that circuit.

a) True

b) False

2. The unit of measurement of electrical power is the

a) ohm

b) volt

c) watt

d) ampere

3. The equation you would use to find the power in a circuit when voltage and current are known is

a) P=E x I

b) P=I x R

c) P=E / I

d) P=I / R

D. C. REVIEW - POWER AND ENERGY

3 - 3


4. When one volt is impressed across the circuit and one ampere of current flows, the power is

a) .1 watt

b) 1 watt

c) 2 watts

d) 10 watts

5. What is the power drawn by a lamp that operates on 120 volts and 2.5 amps flow?

a) 2.5 watts

b) 4.8 watts

c) 48 watts

d) 300 watts

6. In what form would you write the power equation if you know the power used and the circuit voltage and you want to find the current?

3 - 4


7. How much current will be drawn by a heater connected to a 120 volt circuit when 600 watts is consumed?

a) 5 amperes

b) 480 amperes

c) 720 amperes

d) 72,000 amperes

8. One horsepower equals how many electrical watts?

a) 17.46 watts

b) 74.6 watts

c) 746 watts

d) 1,000 watts

9. How many watts does one kilowatt equal?

a) 1 watt

b) 10 watts

c) 100 watts

d) 1,000 watts

3 - 5


10. How much power does a motor use if 27 amperes flow in the circuit when connected to 220 volts? (disregard losses in circuit)

a) 10.8 watts

b) 193 watts

c) 247 watts

d) 5940 watts

11. Assuming no losses, how much current would a 10HP motor draw when connected to a 220 volt circuit?

a) 33.9 amps

b) 460 amps

c) 746 amps

d) 7,460 amps

12. How much power is consumed by a clothes dryer operating on 220 volts and drawing 22 amps?

3 - 6


13. How much power is lost in a length of copper wire that has a voltage drop of 9 volts when 95 amps of current flow through that wire?

a) 10.5 watts

b) 746 watts

c) 855 watts

d) 1,000 watts

14. How many watts of power does a heater use when it has 12 ohms resistance and is connected to a 120 volt circuit? (Check correct answers)

a) 10 watts

b) 1,200 watts

c) 14,400 watts

d) 1.2 kilowatts

15. If the resistance of 1,000 feet of No. 4 copper wire is .2485 ohms, how much power is lost in 1,000 feet of this wire when 70 amps flow through it.

a) 793.3046 watts

b) 1,217.65 watts

c) 4,322,65 watts

d) 12,176.50 watts

3 - 7


16. How much power does a toaster with 30 ohms resistance use when it is connected to a 120 volt source?

17. Which of the following expresses a 7000 watt load in kilowatts?

a) .7 kilowatts

b) 7.0 kilowatts

c) 70.0 kilowatts

d) 700.0 kilowatts

18. Find the line current in the following circuits.

a)

120Vdc

A

24ohms12ohms

R1 R2 R3

P=240watts

3 - 8


b)

A

R1 R2 R3

240Vdc 480watts 1060watts 60ohms

c)

A

R1 R2 R3

480Vdc

A8amps

2238watts

3 - 9


d)

120Vdc

A

R1 R2 R3

A A2amps10amps

.6Kw

e)

A

R1 R2 R32hp 1.2Kw 80ohms240Vdc

3 - 10


f)

120Vdc

A

R1 R2 R3

A

9000watts

150amps

2.4ohms

g)

120Vdc

A

R1 R2 R3

25amps

A

2hp 11ohms

3 - 11


h)

120Vdc

A

R1 R2 R3

A

A 6amps 14amps

Ptotal=3.6Kw

19. Find the total Power in each of the following circuits.

a)

120Vdc

A

24ohms

R1 R2 R3

12amps

240watts

3 - 12


b)

R1 R2 R3480Vdc 10hp 10hp 10Kw

c)

120Vdc

A

R1 R2 R36ohms 18ohms

2.5amps

3 - 13


d)

A

R1 R2 R3

9volts

3amps

.02Kw .002Kw

e)

R1 R2 R3480Vdc 30ohms

A30amps

14.4Kw

3 - 14


20. Find the line current in the following circuits:

a)

120Vdc

A

R1 R2 R3

A 10amps

60ohms 60ohms

b)

120VdcR1 R2 R3

60ohms 240watts 832watts

3 - 15


c)

R1 R2 R3

240Vdc 480watts 720watts 1.2Kw

21. Find the total power in each of the following circuits:

a)

120VdcR1 R2 R3

600watts 250watts 100watts

3 - 16


b)

R1 R2 R3

240Vdc

A 10amps

24ohms 200watts

c) Find the total power in the circuit using 3 different methods:

R1 R2 R3

A

A

3amps

4amps2amps

316Vdc 158ohms 105.33ohms 79ohms

632watts 948watts 1264watts

A

3 - 17


22. If your car has a 1500W block heater and you plug it in every night from 9:00 p.m. to 6:00 a.m., what does it cost you to plug in your block heater for a 30 day period if the rate is 3cts per kWh?

23. Your neighbour has a 1500W block heater with a timer set to operate from 3:00 a.m. to 6:00 a.m. What does it cost him to operate his block heater for a 30 day period if the rate is 3cts per kWh?

3 - 18


24. On a secondary service a 120 volt motor is 500' from the source and is supplied by a conductor having a resistance of .6742 per 1000'. If the motor is a 5 HP, (100% efficient) motor, how much power is used in the lines when the motor is operating at full load if the voltage at the motor is 12OV?

If the motor operates 8 hours. a day for 30 days and the rate is 4cts per kWh what do the line losses cost?

25. A resistor consumes 1.8 kilowatt hours over a 3 hour period. What is the rate at which power is consumed?

If the voltage is 120 volts, what is the current flow?

3 - 19


26. A 25 watt, a 60 watt, and a 100 watt lamp are connected in parallel across a 120 volt supply. All lamps are rated at 120 volts. What is the current drawn by each?

How many hours would the 25 watt lamp have to operate to consume 1 kilowatt hour? The 60 watt lamp? The 100 watt lamp?

27. A current of 8 amps is caused to flow through a 6 ohm resistor. How many watts does it draw?

3 - 20


28. A heating element on an electric stove draws 11 amps from a 120 volt source. How many watts does it draw? If this was used for a total of 28 hours, how many kilowatt hours would be dissipated by the element?

At a cost of 2 cents per kilowatt hour, what would it cost to operate for this period?

3 - 21


29. A load operating from a 240 volt source draws 3,600 watts. How much current does it draw?

How many ohms resistance does the load have?

How much would it cost to operate this circuit for 8 hours a day for 30 days at 5.6 cents/kwhr?

3 - 22

Two-Wire Circuits Review

4 - 2


1. In your own words, describe a two-wire circuit and give an example.

2. Find the voltage available to the following loads:

a)

240 volts

2ohms

2ohms

Load A Load B

A

10amps 10amps

TWO-WIRE CIRCUITS REVIEW

4 - 3


b)

240 volts Load A Load B

A

1.5ohms

1.5ohms

15amps 6.5amps

c)

Load A Load B

A

120 volts

open

2.5ohms

2hp 1.5hp

4 - 4


d)

Load A Load B

A

100volts

3.5ohms

3.5ohms

10ohms 10ohms

4 - 5


3. A two wire service has line wires that possess .5 ohms of resistance for every 100 ft. of conductor. The connected load is 1000 ft. from the source.

Load A Load B

AR1

R2

120volts

40ohms 40ohms

Find the following:

a) The voltage drop in the lines?

b) The voltage available to the loads?

c) Power loss in the lines?

4 - 6


4. A duplex service has a resistance of .2 ohms per 50 feet and is 100' from the source voltage.

Load A Load B

A

12hp 1048watts

50amps

Find:

a) Power lost in lines?

b) Power available to the load?

c) Total power?

d) Voltage drop in the lines?

e) Voltage available to the load?

f) Applied voltage?

4 - 7


5. The voltage across a two wire circuit is 120 volts and the connected load draws 7.5 amps. The service conductor has a resistance of 0.2 ohms per 100' and is connected to the load which is 1000' from the source. What is the voltage drop across the lines and the voltage available to the load?

6. Two motors are connected in parallel across a 110 volt two wire service with a resistance of 2 ohms per line wire. The two motors draw 5 amps each.

Find:

a) The voltage drop in the lines?

b) The voltage available to the loads?

c) Power loss?

d) Total power in the circuit?

What is the cost to operate this circuit for 12 hours a day for 120 days at a rate of 5.6 cents per kilowatt hour?

4 - 8


7. A resistor consumes 2.8 kilowatt hours over a 6 hour period. What is the rate at which power is being consumed?

If the voltage is 120 volts, what is the current flow?

8. On a secondary service, a 120 volt motor is supplied by 500 ft. of duplex having a resistance of .674 ohms per 1000 ft. If the motor is a 5 HP motor, how much energy is lost in the lines when the motor is operating at full load? (The voltage measured at the motor is 120 volts.)

4 - 9


9. In Question # 8, the motor was changed to a 240v - 5Hp motor. What are the line losses now?

Load A Load B

AR1

R2

120volts

116volts3hp

1.5hp

10. What is the resistance in each of the line wires in the above diagram?

What is the length of the service if the conductors display a resistance of .025 ohms per 100 feet?

4 - 10


11. Find the voltage drop in the lines, and the wattage of each of the connected loads.

Load A

A

R1

R2

120volts

2ohms

2ohms

Load B

A

1.5amps

.75amps

What would the voltage drop in the lines be if the wattage of each of the loads were doubled?

4 - 11


4 - 12

Grounding and Bonding Review

5 - 2


1. Define "Grounding" and "Bonding" as stated in the Safety Manual.

2. Now that you have defined "Grounding" and "Bonding" as it is stated in the Safety Manual, explain these terms in your own words and give examples of each.

GROUNDING AND BONDING REVIEW

5 - 3


3. Define "Electromagnetic" induced voltage and give two examples of where it may occur.

4. Define "electrostatic" induced voltage and give an example of where it might occur.

5 - 4


5. How do we as linemen protect ourselves from the effects of "Electrostatic" induced voltages.

Draw a diagram to illustrate your statement.

6. How do we as linemen protect ourselves from the effects of "Electromagnetic" induced voltages? Draw a diagram to illustrate your statement.

5 - 5


7. If Electromagnetic induced voltages can reach values up to 0.1 volt per mile per amp of primary circuit, how many volts could possibly be on a supposedly "dead" power line that is paralleling a 50 mile line that is carrying 300 amps of load? How would you overcome this situation?

8. Keeping in mind your previous statements, what caution must we adhere to when working on insulated shield wires? What possible voltage could be induced on an insulated shield wire that protects a 200 mile, 230,000 volt line that is carrying 200 amps of current? How would you overcome the effects of this situation?

9. What is the difference between "step potential", and "touch potential"? Give examples of each.

5 - 6


10. Theoretically, how could you protect yourself in the event of a ground fault if you happened to be very close to the ground electrode? (2 answers)

11. How far away, and for what reason do we place the grounding electrode from the work area?

12. What size of grounding conductors are required on power lines with the following voltages and fault currents?

a) 25,000 volt - 400A fault current.

b) 72,000 volt - 3600 A fault current.

c) 72,000 volt - 3600 A fault current.

d) 72,000 volt - 12,000 A fault current.

e) 25,000 volt - 12,000 A fault current.

f) 25,000 volt - 4000A fault current.

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13. Indicate the voltages in which we must apply grounds, both line to line and line to ground?

14. List the order in which ground jumpers should be placed while in the act of de-energizing a 25Kv power line.

15. Why must we always apply the grounded conductor to the isolated line first, and be sure that we always remove it last? What would be the possible effects if we did not maintain this procedure?

5 - 8


16. Draw a combination series/parallel circuit to illustrate the effects of grounding and bonding. Use the following values: Electrode to ground - 17.3Ω Pole to ground - 17.3Ω Man - 1.400Ω Pole - 15,000Ω Short Lead - .004Ω Long Lead - .012Ω

5 - 9


5 - 10

Vector Review

6 - 2

Vector Review

1. Answer the following questions referring to the diagram below.

a

b

cHypOpp

Adj

Right Triangle

a) What is the definition of a right triangle?

b) If the angle between b and c is 60 degrees, what is the angle between a and c?

VECTOR REVIEW

6 - 3

Vector Review

c) How would you find an angle if any two sides of the triangle are already determined?

(*Note: there are three possible alternatives - state them all.)

d) What is Pythagoram's theorem?

2. Find side c of the right triangle illustrated below as well as the angle theta.

10

10

a

b

c

6 - 4

Vector Review

3. Find side b and the angle indicated.

a

b

c

2030

?

4. Find sides a and c.

a

b

c

35 degrees

250

6 - 5

Vector Review

5. If we were to travel 10 miles north and 15 miles east, how far and in what direction would we be in relation to our origin?

6. Where would we be if we were to travel 25 miles west, 16 miles north, 40 miles east, and 6 miles south from our origin?

7. Name the two things that are required to construct a vector diagram.

6 - 6

Vector Review

8. With the aid of a protractor, a ruler, and a road map, determine how far and in what direction you are from Weyburn. (the way the crow flies)

6 - 7

Vector Review

9.

12m

12m

3000N

Find the following:

a) Length of guy-wire?

b) Angle of the guy-wire from the ground?

c) Tension on guy-wire?

d) Compression on the pole?

6 - 8

Vector Review

10.

700lbs.

36

15m

Find the following:

a) Distance from anchor to the pole?

b) Length of guy-wire?

c) Tension on the line.

d) Compression on the pole?

6 - 9

Vector Review

11.

52

1250lbs 13m

Find the following:

a) Tension on the line?

b) Tension on the guy?

c) Distance between the pole and anchor?

d) Length of the pole?

6 - 10

Vector Review

12. How much force does the truck have to exert in order to move the truck which is stuck in the slough?

2500lbs.

60

slough

pole

13. Find the tension on each of the slings.

30

3500lbs.

6 - 11

Vector Review

14. Determine the tension on each of the two slings.

60

7 Tons

15. Find the weight of the load. Both slings are of equal length and are at an angle of 30 degrees in relation to the load to be lifted.

30

.56 Tons

6 - 12

Block and Tackle Review

7 - 2


1. How is the mechanical advantage of a set of block and tackle determined? Give an example of your answer.

2. Define friction as it pertains to a set of rope-blocks. Give an example of your answer.

3. What is the friction on a triple sheaf set of rope-blocks if the weight of the object to be lifted is 700 lbs?

BLOCK AND TACKLE REVIEW

7 - 3


4. The tension on a triple sheave set of rope-blocks is 182.86 Kgs. If the blocks are in the running position, what would you suspect the weight of the object being lifted to be?

5. A 600 lb object has to be lifted. How many sheaves would you need to make this lift comfortably, in the running position?

In the standing position?

6. What is the tension on a single sheave set of block and tackle if it is lifting a 135 lb. transformer in the standing position?

In the running position?

7 - 4


7. What other considerations, other than the number of sheaves, must we realize when attempting to make a lift with a set of block and tackle?

8. Calculate the tension in the following:

a)

1200Kg

7 - 5


b)

750 Kg

c)

236 Kg

7 - 6


d)

137 Lbs.

e)

Tension?

800lbs

7 - 7


f)

Tension?

346lbs.

7 - 8

Maps and Survey Review

8 - 2


1. List the characteristics that make up the first system of survey.

2. List the characteristics that make up the second system of survey.

3. List the characteristics that make up the third system of survey.

MAPS AND SURVEY REVIEW

8 - 3


4. What is a correction line?

5. How many meridians affect Saskatchewan? Name these meridians and their locations.

6. In what order should you list the following land descriptions?

a) 3rd meridian

b) section 02

c) township 13

d) Lsd 08

e) NE quarter

f) range 30

g) parcel A

Did you find an error in the above land descriptions?

8 - 4


7. Divide this section into quarter sections, labeling the section and quarter sections according to miles square and acres.

16

8. Divide this quarter section into LSDs and show all measurements.

NE

8 - 5


9. Divide the following LSD into parcels and label accordingly.

16

10. Describe how you would stake a mile of three-phase line and where you put the stakes in relation to the road allowance?

8 - 6

Study Guide Answer Section

9 - 2


D. C. REVIEW - SERIES CIRCUITS

1. c) a conductor

2. a) an insulator

3. True

4. c) resistance

5. c) resistance

6. c) point of positive potential

7. b) volt

8. d) heat

9. b) half as much resistance

10. a) flow of electric current

11. a) I

b) I

c) E

12. a) electrical pressure

13. a) voltage

b) current

c) resistance

14. d) voltage, current and resistance

15. a) E

b) I

STUDY GUIDE ANSWER SECTION

9 - 3


c) R

16. a) resistance

17. b) voltage

18. b) E = IR

d) R = E/I

19. d) 6 amperes

20. d) 48 ohms

21. a) .153 amps

22. a) could be fatal

23. c) 14.067 volts

24. b) can be calculated

d) can be found

25. c) a decrease in current flow

26. False

27. d) 7.33 ohms

28. c) 240 volts

29. True

30. d) 15 amperes

31. b) series circuit

9 - 4


32.

33. True

34. False

35. b) 6.-6 amps

36. c) E E E Eapp = + +1 2 3

37. b) R R R Rt = + +1 2 3

38. a) .333 amps

39. c) 6 amps

40. a)

b)

c) EAPP = 30V + 80V + 120V + 200V = 430V

41. 64 V

9 - 5


D. C. REVIEW - PARALLEL CIRCUITS

1. b) total resistance is always less

2. False

3. a) increases current

4. b) resistance decreases

5. c) 2 ohms

6. RT = 6Ω

7. RT = 10 58. Ω

8. c) 3 ohms

9. RT = 7 5. Ω

10. a) increased

11. b) decreased

12. a) increased

13. True

14. False

15. RT = .08Ω

16. b) parallel

17. b) decreased

18. d) 120 volts

19. a) 10 ohms

20. b) 12 amps

9 - 6


21. a) 6 amps

22. c) 5 amps

23. d) 10 amps

24. b) 3 amps

25. True

26. c) 36 amps

27. a) 3.33 ohms

28. d) 36 amps

29. b) smallest

30. b) decreased

31. True

32. True

33. 20Ω

34. IT = 20a

35. 30 V IR I RT, E , EAPP R= = ×

36. R V V V3 54 18 21 81= = = =Ω, , , ER ER ER1 2 3

37. I1 = 11.6a, I2 = 4a, I3 = 5.8a, IT = 21.4a

38. 40Ω

39. 120 V

40. R2 = 30Ω

41. IT = 19.35a

9 - 7


D. C. REVIEW - POWER AND ENERGY

1. True

2. c) watt

3. a) P = E x I

4. b) 1 watt

5. d) 300 watts

6. I PE

=

7. a) 5 amperes

8. c) 746 watts

9. d) 1,000 watts

10. d) 5940 watts

11. a) 33.9 amps

12. 4840 W

13. c) 855 watts

14. b) 1,200 watts

15. b) 1,217.65 watts

16. 480 W

17. b) 7.0 kilowatts

18. a) IT = 17a

b) IT = 10.41a

c) IT = 12.66a

d) IT = 17a

9 - 8


e) IT = 14.21a

f) R2 = 25a

IT = 150a

g) R1 = 1.65a

h) IT = 30a

19. a) 1440 W

b) 24.92 Kw

c) 3500 W

d) 27 W

e) 28.8 Kw

20. a) 14a

b) 10.93a

c) 10a

21. a) 950 W b) 5 Kw c) 2844 W P P P1 2 3+ + E I× E RT

2 ÷

22. cost = $12.15

23. cost = $4.05

24. a) 323.95 W

b) losses = $3.11

25. a) 600 W

b) 5a

26. .21a, .5a, .83a

40 HRS, 16.66 HRS, 10 HRS

27. 384 W

28 1320 W, 36.96 Kw HRS, cost = $.73

29. 15a, 16Ω, cost = $48.38

9 - 9


TWO-WIRE CIRCUITS REVIEW

2. a) 160 V

b) 175.5 V

c) 0 V

d) 41.66 V

3. a) 40 V

b) 80

c) 160 W

4. a) 2000 W

b) 10 Kw

c) 12000 W

d) 40 V

e) 200 V

f) 240 V

5. ELINES = 30 V

ELOAD = 90 V

6. a) 40 V

b) 70 V

c) 400 W

d) 1100 W

Cost = $88.70

7. 466.6 W, 3.88a

8. 649.5 W

9. 162.3 W

10. .069Ω

276 ft

11. 9V Total, PA = 83.25 W, PB = 166.5 W

EDrop would double to 18 V

9 - 10


GROUNDING AND BONDING REVIEW

7. 1500 volts

Work between grounds that are closer than one mile apart

8. 4000V

Ground using equipotential at the work location

10. i. Stand on one leg and hop out of the electrode area.

ii Put both feet together and don't move.

11. Ten meters away from the work area to avoid the possibility of step potential.

12. a) #4cu

b) #1/0cu

c) #1/0cu

d) #3/0cu

e) #1/0cu

f) #4cu

13. Circuits in excess of 208V RMS to ground or 300V phase to phase

14. i. From a grounded cluster jumper the closest conductor

ii. From the closest conductor jumper the next closest conductor

iii. Finally, jumper the most distant conductor

16.

9 - 11


VECTOR REVIEW

1. a) One with a 90° angle

b) 30°

c) sin∠ =opphyp

cos∠ =adjhyp

tan∠ =oppadj

2. c = 14.14

∠∅ = 45°

3. b = 22.36

∠∅ = 41.8°

4. c = 305

a = 174

5. 18 miles from origin at 56.3° east of north

6. 18 miles 33½° north of east

7. Direction and magnitude

8. Answer will vary

9. a) 16.97m

b) 45°

c) 4242N

d) 3000N

10. a) 20.6m

b) 25.5m

c) 566 lbs

d) 411 lbs

11. a) 1599.9 lbs

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b) 2030 lbs

c) 10.24m

d) 8m

12. 1443 lbs

13. 1811 lbs

14. 8082 lbs

15. .56 tons

BLOCK AND TACKLE REVIEW

1. MA = # of ropes on the moving block

3. 420 lbs

4. 800 Kg

5. 8 running

8 standing

6. Standing T = 81 lbs

Running T = 54 lbs

7. size of rope, size of blocks

8. a) T = 720 Kg

b) T = 262.5 Kg

c) T = 82.6 Kg

d) T - 54.2 lbs

e) T = 134.4 lbs

f) T = 121.1 lbs

9 - 13


MAPS AND SURVEY REVIEW

6. If you are using Parcels and LSD's

a) 6

b) 3

c) 4

d) 2

e) N/A

f) 5

g) 1

If you are using ¼ section descriptions only

a) 5

b) 2

c) 3

d) N/A

e) 1

f) 4

g) N/A

- 3rd Meridian should be West of 3rd or W3

- A detailed map is necessary to determine if parcel A-02 exists at the given township

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