3rd Year Craft Exam

Question 1

__?__ is defined as the shortest distance in inches measured between a point on the top surface of any direct: buried conductor, cable, conduit, or other raceway and the top surface of finished grade, concrete, or similar cover.

Answer 1

Cover

Question 2

A circuit has two capacitors in series. If C_T = 16.67 µF and C_1 = 25 µF what is the value of C_2?

Answer 2

50 µF

Question 3

What is the primary voltage for all dry type transformers in the figure?

Answer 3

480 V

Question 4

What type of study is required to complete an arc flash hazard analysis, including the arc flash boundary and incident energy at a point in
an electrical system?

Answer 4

Short circuit current study

Question 5

The most important factor used to determine the best place to attach to and lift a load is the load’s __?__.

Answer 5

Center of gravity

Question 6

A change to the original blueprints or specifications is accomplished by __?__.

Answer 6

Submitting an addendum

Question 7

The maximum size copper electrode conductor required by the National Electrical Code to a ground rod, pipe, or plate electrode is __?__.

Answer 7

No. 6 AWG

Question 8

Knots that are used to tie the ends of two ropes together are called __?__.

Answer 8

Bends

Question 9

In general, an insulated grounded conductor of __?__ or smaller shall be identified by a continuous white or gray outer finish or by three continuous white stripes on other than green insulation along its entire length.

Answer 9

6 AWG

Question 10

A boom is a long beam that projects from the main part of a crane to __?__ the reach of the hoist.

Answer 10

Extend

Question 11

In grounded systems, an unspliced __?__ connects the equipment grounding conductor and the service-disconnect enclosure to the system’s grounded conductor at each service
disconnect.

Answer 11

Main bonding jumper

Question 12

In a pure capacitive circuit, current will __?__ the voltage by __?__.

Answer 12

lead / 90°

Question 13

Which of the following terms describes the maximum tension that a rigging component may be subjected to while maintaining an appropriate margin of safety?

Answer 13

Rated load

Question 14

What is the maximum number of 6 AWG conductors that may be installed in the 6 x 4 x 2 inch pull?

Answer 14

9

Question 15

A coil has an impedance (X) of 188.4 ohms and an internal resistance (R) of 82 ohms. If the coil is connected to a 120-volt, 60-hertz source, what will be the current through the coil?

Answer 15

0.58 A

Question 16

What is the total impedance (Z_T) in the circuit?

25 Ω | 30 Ω | 240 VAC, 60 Hz

Answer 16

39 ohms

Question 17

Resonance is defined as the __?__ at which inductive reactance is equal to capacitive reactance.

Answer 17

Frequency

Question 18

A __?__ condition represents low impedance fault with the highest level of fault current.

Answer 18

Bolted fault

Question 19

What signal must be given when the load must remain at a constant elevation and move horizontally closer to the crane as the boom is raised?

Answer 19

Raise the boom and lower the load

Question 20

Three capacitors having values of 10 microfarads, 25 microfarads, and 40 microfarads are connected in series. What is the total capacitance of the circuit?

Answer 20

6 µF

Question 21

Exposed non-current-carrying metal parts of fixed equipment supplied by or enclosing conductors that are likely to become energized shall be connected to an equipment grounding conductor where within __?__ vertically or __?__ horizontally of ground or grounded metal objects and subject to contact by persons.

Answer 21

8’ / 5’

Question 22

What kind of crane includes a hoist trolley that travels along a horizontal beam on overhead runways?

Answer 22

Overhead

Question 23

Under most circumstances, if the answer to a question or problem cannot be found on the blueprint drawings, it can be found in the __?__.

Answer 23

NEC

Question 24

The figure represents a(n) __?__. (Alarm panel)

Answer 24

Fire alarm-voice/data/video systems plan

Question 25

What is the name of the structure that extends from the platform of a mobile crane for the purpose of stabilizing the crane?

Answer 25

Outrigger

Question 26

To get an overview of the job to be constructed, one should consult the __?__.

Answer 26

Site plan

Question 27

The NEC allows an underground metallic water pipe to be used as a grounding electrode as long as it has direct contact with the earth for __?__.

Answer 27

10'

Question 28

When looking to see where lighting fixtures will be installed in a T-bar ceiling, one would check the __?__.

Answer 28

Reflected-ceiling drawing

Question 29

For greater strength and permanence (approximately 85% to 90% of the rope itself), a __?__ is used for fastening two ropes together.

Answer 29

Splice

Question 30

Type __?__ cable is a factory assembly of one or more insulated circuit conductors with or without optical fiber members enclosed in an armor of interlocking metal tape, or a smooth or corrugated metallic sheath.

Answer 30

MC

Question 31

In both exposed and concealed locations, where a cable- or raceway-type wiring method is installed through bored holes in joists, rafters, or wood members, holes shall be bored so that the edge of the hole is not less than __?__ from the nearest edge of the wood member.

Answer 31

1-1/4"

Question 32

The sheepshank is primarily used to __?__.

Answer 32

Temporarily shorten rope without cutting it

Question 33

A lighting panel is protected by 150-ampere non-timed delay fuses. What is the minimum size of the aluminum equipment grounding conductor?

Answer 33

4 AWG

Question 34

What is the name of the boundary that an individual worker must observe before he or she works on an energized electrical conductor that has not been placed in an electrically safe work condition?

Answer 34

Limited approach

Question 35

Identify the formula. I_T = √([I_R]^2 + [I_X]^2)

Answer 35

Total current in a parallel AC circuit

Question 36

A drawing that shows conduit size, number of conductors, panel locations, and how the feeders are run is called the __?__.

Answer 36

Riser diagram

Question 37

The knot illustrated is a __?__.

Answer 37

Bowline

Question 38

Where insulating fittings or insulating materials are used with conduits, they shall have a temperature rating __?__ the insulation temperature rating of the installed conductors.

Answer 38

Not less than

Question 39

Where installed in __?__ locations, Type TC Cable shall also be resistant to moisture and corrosive agents.

Answer 39

Wet

Question 40

According to industry recognized practices, the first step in reading a set of commercial prints is to examine the __?__.

Answer 40

Cover sheet for dates and print designations

Question 41

A subpanel in a commercial installation shall have the grounding terminal and neutral bar __?__.

Answer 41

Isolated with only grounding terminal bonded to the enclosure

Question 42

Where Type NM Cable is run at angles with joists in unfinished basements, it shall be permissible to secure cables not smaller than two __?__ or three __?__ conductors directly to the lower edges of the joists. Smaller cables shall either be run through bored holes in joists or on running boards.

Answer 42

6 AWG / 8 AWG

Question 43

When using a sling, what is the minimum recommended sling angle?

Answer 43

30º

Question 44

If 10 equal size electric heater strips are connected in parallel with a 120-volt circuit, and the total circuit current is 8.33 amperes, what is the wattage of each heater strip?

Answer 44

100 W

Question 45

The maximum current that a fuse or circuit breaker can safely interrupt under standard test conditions is called the __?__.

Answer 45

Interrupting rating

Question 46

When applying the (not over) 25 feet long feeder tap rule, conductors shall be permitted to be tapped, without overcurrent protection at the tap, to a feeder provided the ampacity of the tap conductors is not less than __?__ of the rating of the overcurrent device protecting the feeder conductors.

Answer 46

1/3

Question 47

When branch conductors are increased in size to compensate for voltage drop, the sizing of the equipment grounding conductor is __?__.

Answer 47

Adjusted proportionally to the branch conductors

Question 48

A grounding terminal and neutral bar are tied together at __?__.

Answer 48

An autotransformer

Question 49

The characteristic of a fuse in which higher percentage overcurrent faults open faster than lower percentage faults is called the __?__.

Answer 49

Inverse time-current characteristic

Question 50

When a circuit breaker trips due to a fault current that approaches the interrupting rating of the circuit breaker, what does the NFPA 70E standard 225.3 require be done?

Answer 50

Inspect and test the circuit breaker

Question 51

How many breakers are in panel "DP"?

Answer 51

6

Question 52

Which of the following is not considered a common electrical hazard associated with working on or near energized electrical equipment?

Answer 52

Chelation

Question 53

The figure represents a(n) __?__. (Ceiling)

Answer 53

Reflected ceiling plan

Question 54

In a 3-phase delta system the line current is __?__ times the phase current.

Answer 54

1.73

Question 55

What is the total resistance of a circuit containing a branch of three parallel 15-Ω resistors in series with a branch of two parallel resistors (1,000 ohms and 250 ohms)?

Answer 55

5.20 kΩ

Question 56

What does the variable X represent in the formula? X = Watts/Volts-Amps

Answer 56

Power factor

Question 57

Occupational Safety and Health (OSHA) requirements state that only __?__ persons may work on electric circuit parts or equipment that have not been deenergized.

Answer 57

Qualified

Question 58

Where solid rock prevents compliance with the minimum cover depths specified in Table 300.5 of the NEC, the wiring shall be installed in metal or nonmetallic raceway permitted for direct burial. The raceways shall be covered by a minimum of __?__ of concrete extending down to rock.

Answer 58

2"

Question 59

What type of jumper is required to connect the grounding terminal of a grounding-type receptacle to a metal enclosure?

Answer 59

Equipment bonding jumper

Question 60

The grounding electrode conductor in an alternating current system must be sized no less than __?__.

Answer 60

The listing in Table 250.66 of the NEC

Question 61

The low opposition to current for all grounding or grounded conductors is primarily affected by the system's __?__.

Answer 61

Impedance

Question 62

When referring to the specifications for a construction project, in which section of the specifications is information relating to electrical installations located?

Answer 62

Division 16

Question 63

According to the NEC, aluminum electrode conductors used to ground a rod, pipe, or plate electrode should be no larger than __?__ AWG.

Answer 63

No. 4

Question 64

The primary purpose of ground-fault circuit-interrupter protection is to protect personnel against which one of the following?

Answer 64

Faults

Question 65

All 125-volt receptacles located within __?__ from the inside walls of a permanently installed pool shall be protected by a ground-fault circuit-interrupter.

Answer 65

20'

Question 66

The voltage across a capacitor that is charging from a direct current supply will increase __?__ for each time constant.

Answer 66

63.2%

Question 67

The minimum size copper equipment grounding conductor required for a branch circuit protected by a 60-ampere fuse is a __?__.

Answer 67

10 AWG

Question 68

All bends of Type AC Cable shall be made so that the cable will not be damaged, and the radius of the curve of the inner edge of any bend shall not be less than __?__ times the diameter of the Type AC Cable.

Answer 68

5

Question 69

The grounded conductor for copper service-entrance conductors that are larger than 1,100 kcmil shall not be less than __?__ of the area of the largest service-entrance phase conductor.

Answer 69

12.5%

Question 70

Identify the symbol. S_K

Answer 70

Keyed switch

Question 71

A __?__ is a wheel with a concave edge for supporting a moving rope that is changing direction.

Answer 71

Sheave

Question 72

What is the total impedance (Z_T) in the circuit? 100 Ω | 2 H | 120 VAC, 60 Hz

Answer 72

760.21

Question 73

Four branch circuits are installed in the same conduit leaving a distribution panel. One has 15-amp protection, one has 20-amp protection, one has 30-amp protection, and one has 40-amp protection. What is the minimum size of the aluminum equipment ground in the home-run conduit?

Answer 73

8 AWG

Question 74

The service entrance aluminum conductors are 750 kcmil for a 3-phase, 120/208-volt, 4-wire system. What is the minimum size of the aluminum grounding electrode conductor to a pipe electrode?

Answer 74

4 AWG

Question 75

When a copper conductor is used as a grounding electrode conductor, it must be protected if it is smaller than __?__ AWG.

Answer 75

6

Question 76

Electrical nonmetallic tubing (ENT) shall be installed as a complete system and shall be securely fastened in place at intervals not exceeding __?__. In addition, ENT shall be securely fastened in place within __?__ of each outlet or device box, junction box, cabinet, or fitting where it terminates.

Answer 76

3' / 3'

Question 77

A subpanel in a residential installation shall have the grounding terminal and neutral bar __?__.

Answer 77

Isolated with only the grounding terminal bonded to the enclosure

Question 78

In a 3-phase wye system the line current is __?__ times the phase current.

Answer 78

1.73

Question 79

Which one of the following National Fire Protection Association documents is titled the "Standard for Electrical Safety in the Workplace"?

Answer 79

70E

Question 80

The figure represents a __?__. (cfm)

Answer 80

HVAC plan

Question 81

A(n) __?__ person, according to OSHA, is "one who is capable of identifying existing and predictable hazards in the surroundings or working conditions which are unsanitary, hazardous, or dangerous to employees, and who has authorization to take prompt corrective measures to eliminate them."

Answer 81

Competent

Question 82

A lighting panel is protected by a 150-ampere circuit breaker. What is the minimum size of the copper equipment grounding conductor?

Answer 82

6 AWG

Question 83

A detailed list of job requirements covering all work that is to be performed is called a(n) __?__.

Answer 83

Specification

Question 84

When scaled on an electrical blueprint, a conduit stub-up measures 3-/ inches from a wal. If the stub-up is actually supposed to be located 14.5 feet from the wall, what is the correct scale for this blueprint?

Answer 84

1/4" = 1"

Question 85

A parallel RC circuit has a true power of 2,420 watts and an apparent power of 3,102 volt amps. What is the power factor in percent?

Answer 85

78%

Question 86

One horsepower is equal to __?__.

Answer 86

746 W

Question 87

A commonly used knot that does not slip, jam, or fail, is easily tied and untied, and has many uses is the __?__.

Answer 87

Bowline

Question 88

The primary purpose of the main bonding jumper is to __?__.

Answer 88

Carry the ground fault current back to the source

Question 89

Determine the minimum number of 120-volt, 15-ampere lighting circuits required for a dwelling unit with a computed lighting load of 16,000 volt amps.

Answer 89

5

Question 90

Occupational Safety and Health Administration (OSHA) requirements state that while any employee is exposed to contact with parts of fixed electric equipment or circuits which have been deenergized, the circuits energizing the parts shall be __?__ or tagged or both

Answer 90

Locked out

Question 91

The figure represents a(n) __?__.

Answer 91

Feeder riser diagram

Question 92

The service entrance copper conductors are 750 kcmil for a 3-phase, 120/208-volt, 4-wire system. Given this information, what is the minimum size of the copper grounding electrode conductor to a metal water pipe?

Answer 92

2/0 AWG

Question 93

NEC 110.24 (with exceptions) requires that the maximum available fault current be marked on __?__.

Answer 93

Service equipment

Question 94

The provisions in Article 300 are not intended to apply to the conductors that form an integral part of equipment, such as motors, controllers, motor control centers, or factory assembled control equipment or __?__ utilization equipment.

Answer 94

Listed

Question 95

The minimum size of the copper main bonding jumper for a service that consists of one 350 kcmil copper conductor per phase is __?__.

Answer 95

2 AWG

Question 96

The hand signal in the figure is used to tell the crane operator to __?__. (Thumbs down)

Answer 96

Lower the boom

Question 97

A continuous load is a load where the maximum current is expected to continue for __?__ or more.

Answer 97

3 hours

Question 98

What is the minimum size AWG copper conductor permitted for conductors with a 0 through 2,000-volt voltage rating?

Answer 98

No. 14

Question 99

Which item is a suitable grounding electrode?

Answer 99

A 20-foot No. 4 copper conductor encased in 12" of concrete footing

Question 100

The hand signal in the figure is used to tell the crane operator to __?__. "Baseball safe motion"

Answer 100

Stop