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88) Which transformer connection shows a transformer that is connected in a primary delta low, secondary wye low co

B (with little x crosses on windings)

43) If a current of 20 amperes is measured on A phase of a delta-connected transformer, the current through the A phase winding (?)

a. 11.6 A

67) Which of the following is not identified as a method of ensuring an electrically safe work condition?

a. Barricaded to prevent access by unauthorized persons

63) The two standards applicable to the majority of the work performed by Electrical Workers and found in Part 1926 and in Part 1910. Part 1910 applies to .

a. Construction/ General Industry

64) A single winding transformer is more commonly known as a(n) .

a. autotransformer

75) Outlet boxes that do not enclose devices or utilize equipment shall have a minimum internal depth of ?

a. ½"

65) How much power in kilovolt amps is delivered to a 3-phase transformer when the line voltage applied is 240 volts and the line (?)

b. 14.47 kVA

55) Overhead spans of outdoor open conductors, rated at not over 1,000 volts, shall have a minimum clearance from grade of streets and roads.

b. 18'

73) In guest rooms in hotels, motels, and similar occupancies, receptacle outlets shall be permitted to be located (?) least receptacle outlet(s) shall be readily accessible. 210.52(A)

b. 2

51) Nonmetalic-sheathed cable shall be secured in place at intervals not exceeding and within 12 inches from every box, cabinet, or termination.

b. 4 ½'

38) The term "kcmil" is used when referring to cables larger than ?

b. 4/0

) The allowable ampacities listed in Table 310.15(B)(16) of the 2014/2017 NEC are based on an ambient temperature not to exceed .

b. 86°F

66) In a pure inductive circuit, the voltage and the current are with each other.

b. 90° out-of-phase

36) A set of drawing kept up to date as the installations are made and then given to the building owner at the completion are called?

b. As-built

39) The formula represents

b. Impedance in a series LCR circuit

45) The thermal energy resulting in a burn to a worker in an arc-flash event is known as .

c. incident energy

52) If the frequency of a capacitive circuit is decreased, the current will .

c. increase

50) A circuit supplied with a 277-vold, 60-hertz source is connected with a capacitive reactance of 23.35 ohms. What is the current?

d. 11.86 A

44) A transformer has a secondary voltage of 120 volts. The primary winding has 1,800 turns and the secondary has 90 turns. What is the primary voltage?

d. 2,400 V

46) What is the peak-to-peak voltage for an AC voltage source with a root mean square (RMS) value of 120 volt?

d. 339.36 V

68) A is an electromagnetic device that changes voltage from one level to another.

d. transformer

71) What type of plan shows the location of the structure in relation to the lot, road, or to other structures?

d. view

49) Live parts to which an employee might be exposed must be deenergized before the employee works on or near them, unless the can demonstrate that deenergizing introduces additional or increased hazards or is infeasible due to equipment design or operational limitations.

employer

60) Which type of view gives a pictorial representation of an object on a drawing?

holographic

54) Three-way and four-way switches shall be so wired that all switching is done only in the circuit conductors.

ungrounded

93) Identify the Item

⦁ Combination bell/buzzer

70) Identify the item.

⦁ Switch with pilot light

⦁ Identify the connection types on the buck-boost transformer

⦁ Voltage boost connection

⦁ If a current of 30 amperes is measured on B phase of a wye-connected transformer, the current is:

⦁ 30.0 A

80) The current through branch I1 is ____?

⦁ 3A

79) It takes _____ time constants to fully charge a capacitor.

⦁ 5

⦁ What is the correct ground-fault circuit interrupter (GFCI) level for a class A device?

⦁ 5 mA

⦁ The load for household electric clothes dryers in a dwelling unit(s) shall be ___ or the nameplate rating

⦁ 5,000 W (VA) NEC 220.54

⦁ Where the NEC requires that one piece of equipment shall be "in-sight" from another piece of equipment, the spec.......... More than ___ from the other equipment

⦁ 50

⦁ A 48-microfarad capacitor has a voltage drop of 30 volts across it in a 60-hertz AC circuit. How much current is flowing?

⦁ 542 mA

⦁ The formula is ___ ?

⦁ Capacitive Reactance

⦁ The capacitive reactance of a circuit is determined by the ___ ?

⦁ Frequency and Capacitance

⦁ A transformer with more windings on the load side than on the line side is known as a ____ transformer

⦁ Step-up

⦁ Identify the item

⦁ Transformer

77) Each multiwire branch circuit shall be provided with a means that will simultaneously disconnect all _____ conductors?

⦁ Ungrounded 210.4(B)

74) The figure shows a(n) ?

⦁ wave shape of an AC voltage sine wave

48) What is the standard unit of measure for transformer capacity?

b. Kilovolt-amps

58) In a series LC circuit, when XC equals XL, the total impedance Z .

b. approaches minimum

69) To find information about light fixtures on the job including fixture type, manufacturers, lamp numbers, and mounting instructions?

b. lighting fixture schedule

61) A circuit has a coil with inductance of 3 henries and is connected to a 60-hertz, 120-volt source. How much current flows?

b.106 mA

56) A motor consumes 248.67 watts of power. What is the horsepower rating of the motor? (Neglect heat losses.)

c. 1/3 hp

41) A coil has an X L of 150 ohms, and a resistor connected in series has a resistance of 100 ohms. What is the impedance of the circuit?

c. 180

47) A series circuit contains four inductors with the following inductance values: 3.5 henries, 35 millihenries, 6 henries, and 25 millihenries. How many henneries is the circuit?

c. 9.7850 H

57) Match the term "henry" with the choice that closes describes its use.

c. Unit of inductance

40) In a purely capacitive circuit, ?

c. current leads voltage by 90°

62) How many degrees separate the phases of a 3-phase transformer system?

120

In a 60 hertz single-phase AC circuit, how many times does the voltage drop to zero each Second?

120

53) Determine the applied voltage.

b. 80 V

82) In every kitchen, family room, dining room, living room, parlor, library, den, sunroom, bedroom, recreation room outlets shall be installed so that no point along the floor line in any wall space is more than _____ measured horizontally from the center of the wall.

⦁ 6'

⦁ Where buildings exceed three stories or 15m (50ft) inheight, overhead lines shall be arranged, where Practicable, so that a clear space (or zone) at least ___ wide will be left either adjacent to the building or beginning not over ___ from them to facilitate the rising of ladders when necessary for firefighting

⦁ 6' / 8' 225.19(E)

99) The value of R2 ____?

⦁ 60Ω

84) A 380-milihenry coil has 12 volts at 60 hertz dropped across it. What is the current flowing through the coil?

⦁ 83.8 mA

96) A 480-ohm inductor has a voltage drop of 40 volts across it. How much current is flowing through the coil?

⦁ 83mA

⦁ A transformer has a turn ratio of 1:2. By applying 480 volts to the primary of this transformer, the secondary voltage is:

⦁ 960 V

59) Identify the item.

⦁ Bell

81) Two capacitors of 3 and 6 microfarads are connected in parallel to a 120-volt, 60-hertz source. What is the maximum ampacity?

⦁ 0.407 A

100) There are three capacitors in parallel. Their values are: C1=0.25µF, C2=0.30µF, and C3=0.35µF. What is the total (question cuts off).

⦁ 0.900 µF

⦁ What is the total inductive reactance of a 60 - hertz AC circuit with 50 ohms of resistance and 4 henries of inductance?

⦁ 1,507.2 ohms

⦁ Three coils with inductance of 2, 4, and 5 henries are connected in parallel. What is the total inductance of the circuit?

⦁ 1.05 H

⦁ Three capacitors of 2, 4, and 6, microfarads connected in series have a total capacitance of ___ ?

⦁ 1.09 µF

⦁ A power transmission line has a current of 84 amps flowing through the conductor, and the conductor resistance is.......... Transmission line?

⦁ 10,164 W

78) Determine the total impedance Z in the figure.

⦁ 10.8𝛀

86) In the secondary winding of the single-phase transformer, if the current in Phase A is 25 amps, and the current in (this section cut off) Neutral (N)?

⦁ 12.5A

83) If each secondary winding is rated at 120 volts alternating current (VAC), what would the voltage between

⦁ 120 VAC

⦁ In general, each 1000-volt transformer, nominal, or less that has protection on the primary winding only, shall be protected on the primary side, rated or set at not more than ___ of the rated primary current of the transformer

⦁ 125%

⦁ The length of side Z is ___ ?

⦁ 15.6

⦁ An electrical worker is reading a blueprint that uses a ⅛-inch to 1-foot scale. The ruler measures 2 ⅜ inches. What is the total measuring?

⦁ 19' 0"

⦁ If a 3-phase, single voltage, wye-connected transformer is supplied by 4,160 volts, the voltage across each winding is

⦁ 2,405 V

⦁ What would be the current through a 150-millihenry coil connected across a 120-volt, 60-hertz

⦁ 2.12 A

⦁ For show window loads calculated by the food, a load of not less than ___ shall be included for each one

⦁ 200 VA 220.14(G)

⦁ Dwelling unit receptacle outlets serving kitchen wall countertop spaces shall be installed so that no point along....... A receptacle outlet in that space

⦁ 24''

⦁ Identify the symbol

⦁ 250 Range Outlet

⦁ Where connected to a branch circuit supplying two or more receptacles or outlets, receptacle ratings shall conform to the values listed in the NEC, or, where rated higher than ___ amperes, the receptacle rating shall not be less than the branch-circuit rating.

⦁ 50 A NEC 210.23(B)(3)

⦁ Rigid PVC conduit larger than ___ trade size shall not be used

⦁ 6"

98) A 750-microfarad capacitor is connected to a 277-volt, 60-hertz source circuit. How much curren(question cut off)

⦁ 980mA

76) Arc-rated suits and clothing are designed to protect electrical workers from _____?

⦁ Arc-flash

⦁ Which item is not measured in Ohms?

⦁ Capacitance

94) Connecting additional inductors in a series circuit will cause the circuit current to ___?

⦁ Decrease

87) When the frequency of a purely inductive circuit is decreased, the current in the circuit ___?

⦁ Decreases

⦁ Which print shows the face views of the building or residence?

⦁ Elevation

97) For a wye-connected transformer, the current carried by the windings is ___ the line current of the phas(rest of question cut off)

⦁ Equal to

90) The primary leads of a transformer are identified with the letter ____?

⦁ H

⦁ If the frequency is increased in a series RL circuit, the impedance will ___ ?

⦁ Increase

⦁ The symbol "L" is used in drawings to identify ___ ?

⦁ Inductance

89) In general, all service-entrance conductors entering or on the exterior of buildings or other structures shall be ___?

⦁ Insulated

⦁ Which item listed is classified as a fitting in reference to a wiring system?

⦁ Locknut

85) The schedule that lists details relating to circuits, breakers, and the main disconnect is the _____ schedule?

⦁ Panel

⦁ ___ is a direct result of an arc-blast event

⦁ Pressure

⦁ This transformer is connected ___ ?

⦁ Primary delta - secondary delta

Identify the connection types on the transformer

⦁ Primary delta high - secondary delta high

72) Identify the connection types on the transformer.

⦁ Primary delta high - secondary wye high

91) The skin's ____ can change as a function of the moisture present in its external and internal layers and can be alt(rest of word cut off) fear, and anxiety

⦁ Resistance

⦁ The ability of an inductor in a transformer to generate inductive reactance, which opposed changes in the circuit is called

⦁ Self-Inductance


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