1. Smitty’s Two Minute Drill General Knowledge
© Ted Smith 2017
Electrical Experts Consulting

2. Click on the slide to start the timer and begin the test
Be sure to place this presentation in Slide Show Mode if it is not already in that mode before proceeding
The purpose of this drill is to help you improve your skill at finding answers to questions using the applicable fire codes and also to help increase your knowledge of the Fire Alarm codes.
Each slide will contain a question. The question will remain in the screen for a period of 2 minutes then a notification will sound and the slide will transition to the next slide with the answer. After 15 seconds the next question will appear.
During the test do not worry about the correct answers when those slide appear. You will be given an opportunity to review the answers with out the time at the end of the test.
Click on the slide to start the timer and begin the test
Instructions

3. This drill is based on general knowledge
This drill is based on general knowledge. None of the answers to these questions will be found in the NEC. These are all things which we learn as part of our electrical apprenticeship.
These type of questions are found in the general knowledge category of the examination which has 10 questions.
This is the only part of the test that is basically a knowledge test and not a code look up test.
NOTE

4. Ohms Law basics
P=I x E and E= I x R
Ohms law. “It requires 1 volt of EMF to push 1 ampere of current through 1 ohm of resistance to experience 1 watt of power.”
Power factor is determined by Dividing the True Power measured in Watts by the Apparent Power measured in VAs. For example: What is the power factor of a 7200 Watt load that has a current of 33 amperes and is operating at 240 volts single phase. The apparent power is determined by multiplying the voltage by the current. So to determine the power factor you would first multiply 33 x 240= 7920 VA. Then you would divide the True power watts by the apparent power 7920 VA. 7200/7920= which would be a power factor of 90.9 percent.
Power in a three phase circuit is determined by multiplying the voltage x x the current in the circuit. For example, what is the power in three phase circuit that is 208 volts and has a current of 82 amperes. 208 x x82= 29, VAs.
REMEMBER

5. 1 horse power (hp) is equal to 746 watts.
REMEMBER
1 horse power (hp) is equal to 746 watts.

6. NEC
1. One kVA is equal to
100 VA
1000 Volts
1000 VA
10,000 VA

7. Answer C
1 kVA=1 VA times 1000

8. NEC
2. 5,000 watts is equal to ___________.
500 kW
5 kW
0.50 kW
50 kW

9. Answer B.
5000/1000=5kW

10. NEC
3. Where a 120 volt microwave oven is rated 1,200 watts, how much current, in amperes, will the microwave draw?
0.10 amperes
5 amperes
10 amperes
15 amperes

11. Answer C.
I=1200/120=10 amperes

12. NEC
4. When an electric hair dryer draws six (6) amperes when connected to a 120 volt source, the rating of the hair dryer is ______________.
720 watts
750 watts
20 watts
200 watts

13. P=6 amperes x 120 volts= 720 watts
Answer A.
P=6 amperes x 120 volts= 720 watts

14. NEC
5. When a 240 volt, single phase branch circuit has a current flow of 20 amperes, what is the resistance, in ohms, of this branch circuit?
3 ohms
6 ohms
9 ohms
12 ohms

15. Answer D
R= 240 volts/20 amps= 12 ohms

16. NEC
6. When a 2 kW electric baseboard heater is connected to a 240-volt, single phase circuit, the current flow in the circuit is ____________.
4.15 amperes
8.33 amperes
12.50 amperes
16.66 amperes

17. I=(2kW x1000)/240 volts=2000/240= 8.33 amperes
Answer B
I=(2kW x1000)/240 volts=2000/240= 8.33 amperes

18. NEC
7. Determine the power consumed, in VA, by a lighting load that operates at 115 volts and has a power factor of 80%.
1,150 VA
960 VA
920 VA
736 VA

19. Answer D
P=8 amps x 115 volts x .80= 736 VA

20. NEC
8. A 150 ampere rated, 120/240 volt, single phase residential service will have a Volt-ampere rating of _____________.
A. 180,000 VA
B. 90,000 VA
C. 36,000 VA
D. 72,000 VA

21. Answer C
P=240 volts x 150 amps=36,000 VA

22. NEC
9. A 15 kW, 208 volt, single phase heat pump will have a full load current rating of ___________.
72 amperes
46 amperes
66 amperes
33 amperes

23. Answer A
I=(15kW x 1000)/208=15,000/208=72 amperes

24. NEC
10. What is the power factor of a 6,500 watt load that draws 33 amperes of current when connected to a 240 volt, single phase source?
1.12 percent
82 percent
68 percent
1.04 percent

25. Answer B
PF= 6500 watts/(240 volts x 33 amps)=6500 watts/7920 VA= .82 or 82 percent power factor

26. NEC
11. Given an electric baseboard heater has a total resistance of 22 ohms and is supplied with a 240 volt, single phase power source. Determine the current.
10.9 amperes
21.8 amperes
0.09 amperes
1.01 amperes

27. I=240 volts/22 ohms= 10.90 amperes
Answer A
I=240 volts/22 ohms= amperes

28. NEC
12. The power factor of a 5 kW load drawing 30 amperes of current when connected to a 208 volt, single phase source is _____________.
92 percent
46 percent
80 percent
83 percent

29. Answer C
PF= (5kW x 1000)/(208 volts x 30 amps)= 5000/6240=.80 or 80 percent power factor

30. NEC
13. A 200 ampere rated, 208 Y connected, three phase, four wire commercial service will have VA rating of _________________.
360 VA
43,231 VA
41,600 VA
72,051 VA

31. Answer D
VA=208 volts x x 200 amps= 72,051 VA

32. NEC 14. Ohm’s law is a relationship between ________________.
Current, voltage and amperes
Current ,EMF, power, resistance
Voltage, Current, and Resistance
Voltage, Power, and Resistance

33. Answer B
Ohms law. “It requires 1 volt of EMF to push 1 ampere of current through 1 ohm of resistance to experience 1 watt of power.”

34. NEC
15. What is the rated secondary current of a 600 VA, single phase transformer at unity power factor, that has a 200 volt input and a 15 volt secondary?
10 amperes
20 amperes
13 amperes
40 amperes

35. Answer D
I=600 VA/15 volts= 40 amperes

36. NEC
16. Determine the line current, in amperes, on a balanced wye connected three phase electrical system with a load of 25 kVA per phase and line voltage of 208 volts. The total power is 75 kVA.
87 amperes
144 amperes
208 amperes
360 amperes

37. I=75000 VA/(208 volts x 1.732)= 75000/360.25=208.3 amperes
Answer C
I=75000 VA/(208 volts x 1.732)= 75000/360.25=208.3 amperes

38. NEC
17. If an industrial type HID luminaire, rated 300 watts, is connected to a 120 volt branch circuit and is drawing three amperes of current, the luminaire has a power factor of _____________.
83 percent
93 percent
1.2 percent
79 percent

39. Answer A
PF= 300 watts/(120 volts x 3 amps)=300/360=.83 or 83 percent power factor

40. NEC 18. 5 horsepower is equal to ____________ 5 kW 3,730 watts
5 kVA

41. Answer B
5 HP x 746 watts= 3,730 watts

42. NEC
19. When eight (8) 400 watt metal halide luminaires, each having a power factor of 86 percent, are connected to a 277 volt, single phase lighting branch circuit, the full load current (FLC) of the luminaire will be ______________.
11.55 amperes
5.54 amperes
13.43 amperes
6.68 amperes

43. I= 400 watts/(277 volts x .86)=400/238.22= 1.679 amperes
Answer C
I= 400 watts/(277 volts x .86)=400/238.22= amperes

44. NEC
20. When a 400 ampere rated commercial service is supplied with a 480 volt wye connected, three phase, four wire electrical system, the service has a rating of _______________.
kVA
110.8 kVA
192.0 kVA
332.5 kVA

45. Answer D
P= (400 A x 480 V x 1.732)/1000=332,544 VA/1000= kVA

46. END of QUIZ. THE TIME WILL STOP NOW
END of QUIZ. THE TIME WILL STOP NOW. PLEASE CLICK ON THE SLIDE TO CONTINUE WITHOUT THE TIMER AND REVIEW EACH QUESTION.

47. NEC
1. One kVA is equal to
100 VA
1000 Volts
1000 VA
10,000 VA

48. Answer C
1 kVA=1 VA times 1000

49. NEC
2. 5,000 watts is equal to ___________.
500 kW
5 kW
0.50 kW
50 kW

50. Answer B.
5000/1000=5kW

51. NEC
3. Where a 120 volt microwave oven is rated 1,200 watts, how much current, in amperes, will the microwave draw?
0.10 amperes
5 amperes
10 amperes
15 amperes

52. Answer C.
I=1200/120=10 amperes

53. NEC
4. When an electric hair dryer draws six (6) amperes when connected to a 120 volt source, the rating of the hair dryer is ______________.
720 watts
750 watts
20 watts
200 watts

54. P=6 amperes x 120 volts= 720 watts
Answer A.
P=6 amperes x 120 volts= 720 watts

55. NEC
5. When a 240 volt, single phase branch circuit has a current flow of 20 amperes, what is the resistance, in ohms, of this branch circuit?
3 ohms
6 ohms
9 ohms
12 ohms

56. Answer D
R= 240 volts/20 amps= 12 ohms

57. NEC
6. When a 2 kW electric baseboard heater is connected to a 240-volt, single phase circuit, the current flow in the circuit is ____________.
4.15 amperes
8.33 amperes
12.50 amperes
16.66 amperes

58. I=(2kW x1000)/240 volts=2000/240= 8.33 amperes
Answer B
I=(2kW x1000)/240 volts=2000/240= 8.33 amperes

59. NEC
7. Determine the power consumed, in VA, by a lighting load that operates at 115 volts and has a power factor of 80%.
1,150 VA
960 VA
920 VA
736 VA

60. Answer D
P=8 amps x 115 volts x .80= 736 VA

61. NEC
8. A 150 ampere rated, 120/240 volt, single phase residential service will have a Volt-ampere rating of _____________.
A. 180,000 VA
B. 90,000 VA
C. 36,000 VA
D. 72,000 VA

62. Answer C
P=240 volts x 150 amps=36,000 VA

63. NEC
9. A 15 kW, 208 volt, single phase heat pump will have a full load current rating of ___________.
72 amperes
46 amperes
66 amperes
33 amperes

64. Answer A
I=(15kW x 1000)/208=15,000/208=72 amperes

65. NEC
10. What is the power factor of a 6,500 watt load that draws 33 amperes of current when connected to a 240 volt, single phase source?
1.12 percent
82 percent
68 percent
1.04 percent

66. Answer B
PF= 6500 watts/(240 volts x 33 amps)=6500 watts/7920 VA= .82 or 82 percent power factor

67. NEC
11. Given an electric baseboard heater has a total resistance of 22 ohms and is supplied with a 240 volt, single phase power source. Determine the current.
10.9 amperes
21.8 amperes
0.09 amperes
1.01 amperes

68. I=240 volts/22 ohms= 10.90 amperes
Answer A
I=240 volts/22 ohms= amperes

69. NEC
12. The power factor of a 5 kW load drawing 30 amperes of current when connected to a 208 volt, single phase source is _____________.
92 percent
46 percent
80 percent
83 percent

70. Answer C
PF= (5kW x 1000)/(208 volts x 30 amps)= 5000/6240=.80 or 80 percent power factor

71. NEC
13. A 200 ampere rated, 208 Y connected, three phase, four wire commercial service will have VA rating of _________________.
360 VA
43,231 VA
41,600 VA
72,051 VA

72. Answer D
VA=208 volts x x 200 amps= 72,051 VA

73. NEC 14. Ohm’s law is a relationship between ________________.
Current, voltage and amperes
Current ,EMF, power, resistance
Voltage, Current, and Resistance
Voltage, Power, and Resistance

74. Answer B
Ohms law. “It requires 1 volt of EMF to push 1 ampere of current through 1 ohm of resistance to experience 1 watt of power.”

75. NEC
15. What is the rated secondary current of a 600 VA, single phase transformer at unity power factor, that has a 200 volt input and a 15 volt secondary?
10 amperes
20 amperes
13 amperes
40 amperes

76. Answer D
I=600 VA/15 volts= 40 amperes

77. NEC
16. Determine the line current, in amperes, on a balanced wye connected three phase electrical system with a load of 25 kVA per phase and line voltage of 208 volts. The total power is 75 kVA.
87 amperes
144 amperes
208 amperes
360 amperes

78. I=75000 VA/(208 volts x 1.732)= 75000/360.25=208.3 amperes
Answer C
I=75000 VA/(208 volts x 1.732)= 75000/360.25=208.3 amperes

79. NEC
17. If an industrial type HID luminaire, rated 300 watts, is connected to a 120 volt branch circuit and is drawing three amperes of current, the luminaire has a power factor of _____________.
83 percent
93 percent
1.2 percent
79 percent

80. Answer A
PF= 300 watts/(120 volts x 3 amps)=300/360=.83 or 83 percent power factor

81. NEC 18. 5 horsepower is equal to ____________ 5 kW 3,730 watts
5 kVA

82. Answer B
5 HP x 746 watts= 3,730 watts

83. NEC
19. When eight (8) 400 watt metal halide luminaires, each having a power factor of 86 percent, are connected to a 277 volt, single phase lighting branch circuit, the full load current (FLC) of the luminaire will be ______________.
11.55 amperes
5.54 amperes
13.43 amperes
6.68 amperes

84. I= 400 watts/(277 volts x .86)=400/238.22= 1.679 amperes
Answer C
I= 400 watts/(277 volts x .86)=400/238.22= amperes

85. NEC
20. When a 400 ampere rated commercial service is supplied with a 480 volt wye connected, three phase, four wire electrical system, the service has a rating of _______________.
kVA
110.8 kVA
192.0 kVA
332.5 kVA

86. Answer D
P= (400 A x 480 V x 1.732)/1000=332,544 VA/1000= kVA