2123
When supplying a room air conditioner rated 120V, the length of a flexible supply cord shall not exceed _____ ft.
10 440.64
What size conductor should be used to limit voltage drop from exceeding three percent if the equipment nameplate indicates an 18A continuous load at 480V, three-phase and its located 300 ft from the power supply?
10 AWG
A raceway contains eight current-carrying conductors. What size conductor is required to feed a 21A noncontinuous lighting load in a dry location? The overcurrent protection device is rated 30A.
10 THHN
Handhole enclosure covers shall require the use of tools to open, or they shall weigh over _____ lb.
100 314.30(D)
Two 8 AWG copper conductors supply a 120V load that's located 225 ft from the panelboard. What's the maximum load in amperes that can be applied to these conductors without exceeding the NEC recommendation for conductor voltage drop?
10A
The reading on Voltmeter 2 (V2) is _____. See Figure.
10V
What's the VA load for the following motors: 2 hp at 120V; 3 hp at 208V, single-phase; 5 hp at 208V, three-phase; 30 hp at 480V, three-phase; and 50 hp at 480V, three-phase?
113,588 VA
Motors that have a service factor rating of 1.10 must have the overload protection device sized at not more than _____ percent of the motor nameplate ampere rating.
115
Type AC cable shall be secured at intervals not exceeding 4 1/2 ft and within _____ in. of every outlet box, cabinet, conduit body, or fitting.
12 320.30(B)
The secondary winding of a transformer operates at 24V and it supplies a load that has a rating of 5A. If the transformer is rated 90 percent efficient, what's the secondary VA load rating?
120 VA.
The minimum feeder conductor ampacity shall be no less than the noncontinuous load plus _____ percent of the continuous load, and not less than the maximum load after the application of adjustment and correction factors.
125 215.2(A)(1)(a)
The branch-circuit short-circuit and ground-fault protection device for a 10 hp, 230V, single-phase motor must not exceed _____. Note: Use an inverse time breaker.
125A
The minimum size copper conductor permitted for branch circuits under 600V is _____ AWG.
14 310.106(A) and Table 310.106(A)
The numeric equivalent of 122 is _____.
144
Receptacle outlets that are a part of a _____ kW or smaller portable generator shall have listed ground-fault circuit-interrupter protection (GFCI) for personnel integral to the generator or receptacle.
15 445.20
According to Table 8 of Chapter 9, what's the cross-sectional area in circular mills for a 3/0 THHN aluminum conductor?
167,800
A transformer primary winding operates at 240V, the secondary winding operates at 12V, and the secondary load is two 100W lamps. What's the secondary current flow if the transformer winding is rated 80 percent efficient?
17A
Where used outside, aluminum or copper clad aluminum grounding electrode conductors shall not be terminated within _____ in. of the earth.
18 250.64(A)
When installing PVC conduit underground without concrete cover, there shall be a minimum of _____ in. of cover.
18 300.5(A) and Table 300.5 Column 3
The smallest size fixture wire permitted by the NEC is _____ AWG.
18 402.6
For other than dwelling occupancies, banks, or office buildings, each receptacle outlet shall be calculated at not less than _____ VA.
180 220.14(I)
In a purely inductive circuit, the CEMF waveform is _____ out-of-phase with the applied voltage waveform.
180°
What's the maximum distance a 240V, single-phase, 10A continuous load can be located from the panelboard so the voltage drop doesn't exceed three percent? The load is wired with 12 AWG.
182 ft
Galvanized steel, stainless steel, and red brass RMC shall be permitted in or under cinder fill subject to permanent moisture, when protected on all sides by a layer of noncinder concrete not less than _____ in. thick.
2 344.10(C)
A 2 hp, 120V motor requires a _____ branch-circuit short- circuit and ground-fault protection device. Note: Use an inverse time breaker.
60A
The feeder protection for one 25 hp, 208V, three-phase motor, and three 3 hp, 120V, single-phase motors will be _____ after balancing. Note: Use inverse time breakers.
225A
What's the required feeder short-circuit ground-fault protection (inverse time circuit breaker) for one 50 hp (5-minute varying duty motor), one 20 hp, and two 10 hp motors where all motors are rated 480V, three-phase?
225A
A 40A, 240V rated single-phase load is 150 ft from a junction box and the junction box is located 50 ft from a panelboard (for a total of 200 ft). If the voltage at the panelboard is 240V, what's the minimum voltage recommended by the NEC at the 40A load?
232.80V
What's the maximum distance a 100A, 208V, three-phase noncontinuous load wired with 1 AWG conductors can be located from the panelboard so the voltage drop doesn't exceed three percent?
234 ft
How many 18 TF conductors can be installed in trade size 3/4 electrical metallic tubing?
24 conductors
The minimum horizontal dimension for the junction box shown in the diagram in the Figure is _____.
24 in.
The grounded conductor brought to service equipment shall be routed with the phase conductors and shall not be smaller than specified in Table _____ when the service entrance conductors are 1,100 kcmil copper and smaller.
250.102(C)(1) 250.24(C)(1)
Electrical equipment permanently mounted on skids, and the skids themselves, shall be connected to the equipment grounding conductor sized as required by _____.
250.122 250.112(K)
If the primary phase voltage is 480V and the secondary phase voltage is 240V, the turns ratio is _____.
2:01
If the transformer winding voltage turns ratio is 5:1 and the current flowing through the secondary winding is 10A, the current flowing through the primary winding will be _____.
2A
The vertical clearance of final spans of overhead conductors above or within _____ ft measured horizontally of platforms, projections, or surfaces that will permit personal contact shall be maintained in accordance with 225.18.
3 225.19(D)(2)
For Types NM and NMC cable, the conductor ampacity used for ambient temperature correction [310.15(B)(2)(a)], conductor bundling adjustment [310.15(B)(3)(a)], or both, is based on the 90º C conductor insulation rating [310.15(B)(2)], provided the final calculated ampacity does not exceed that of a _____ rated conductor.
60º C 334.80
If the input power of a 1 hp direct-current motor is 1,128W and the output power is 746W, what's the efficiency of the motor?
66%
According to Table 8 of Chapter 9, what's the cross-sectional area in circular mills for a 2 RHH conductor?
66,360
The secondary voltage of the transformer shown in the Figure is _____.
6V
How many 20A, 120V circuits are required for forty-two, 300W HID luminaires (assume this is a noncontinuous inductive load) that have a power factor of 85 percent?
7
When determining the number of conductors in a box that has one 14/3 W/G NM cable, one switch, and two internal cable clamps, the count will equal _____.
7 conductors
Where installed in raceways, conductors _____ AWG and larger shall be stranded, unless specifically permitted or required elsewhere in the NEC.
8 310.106(C)
The minimum radius of a field bend on trade size 1 1/4 RMC is _____ in.
8 344.24 and Chapter 9, Table 2
TPT and TST cords shall be permitted in lengths not exceeding _____ ft when attached directly to a portable appliance rated 50W or less.
8 Table 400.4 Note 11
What size THW conductor is required for a 5 hp, 230V single phase motor?
8 AWG
What size feeder protection and conductors are required for the following two motors? Motor 1 - 7 1/2 hp, 208V, three-phase: FLC = 24.20A [Table 430.250]; Motor 2 - 5 hp, 208V, single-phase: FLC = 30.8A [Table 430.248]; Motor 3 - 1 hp, 115V, single-phase: FLC = 16A [Table 430.248]
A 100A breaker.
What's the approximate output of a 5 hp, 480V, three-phase motor?
3.75 kW
The ampacity adjustment factors in 310.15(B)(3)(a) shall be applied to a metal wireway only where the number of current-carrying conductors in any cross section of the wireway exceeds _____.
30 376.22(B)
Receptacles shall not be grouped or ganged in enclosures unless the voltage between adjacent devices does not exceed _____.
300v 406.5(I)
What's the approximate square root of 1,000?
32
The reading of V4 is _____. See Figure.
3v
When a 100W, 115V lamp operates at 230V, the lamp will consume approximately _____ when the total resistance is 132.25 ohms. P = E2/R
400W
What size nontime-delay fuses are required for a 2 hp, 230V, single-phase motor?
40A
The load for electric clothes dryers in a dwelling unit shall be _____ watts or the nameplate rating, whichever is larger, per dryer.
5000 220.54
The primary current of the 480/208V transformer shown in the Figure is _____.
50A
The primary load in watts for a transformer (rated 95 percent efficient) that supplies a 500W load is _____. See Figure.
526W
A load is located 100 ft from a 230V power supply and is wired with 4 AWG aluminum conductors. What size copper conductors can be used to replace the aluminum conductors and not increase the conductor voltage drop?
6 AWG
The decimal equivalent for the fraction "1/2" is _____.
0.50
What size THHN feeder conductor is required for one 50 hp (5-minute varying duty motor), one 20 hp, and two 10 hp motor where all motors are rated 480V, three-phase?
1/0 AWG
How much time does it take for 60 Hz alternating current to travel through 180 degrees?
1/120 second
Surface-type cabinets, cutout boxes, and meter socket enclosures in damp or wet locations shall be mounted so there is at least _____-in. airspace between the enclosure and the wall or supporting surface.
1/4 312.2
Where nonmetallic-sheathed cable or multiconductor Type UF cable is used, the sheath shall extend not less than _____ in. inside the box and beyond any cable clamp.
1/4 314.17(B)
The point of attachment of overhead premises wiring to a building shall in no case be less than _____ ft above finished grade.
10 225.16(A) and 230.26
Overhead service conductors shall have a horizontal clearance of not less than _____ ft from a pool.
10 230.24(D), 680.9(A), and Table 680.9(A)
Constant-voltage generators, except ac generator exciters, shall be protected from overload by _____ or other acceptable overcurrent protective means suitable for the conditions of use.
ANY OF THESE 445.12(A)
The continuity of a grounded conductor shall not depend on a connection to _____.
ANY OF THESE a metallic enclosure, a raceway, cable armor 200.2(B)
_____ is the value of the voltage or current at a moment of time.
Instantaneous
_____ is a raceway of circular cross section having an outer liquidtight, nonmetallic, sunlight-resistant jacket over an inner flexible metal core.
LFMC 350.2 Liquidtight Flexible Metal Conduit (LFMC)
Power loss in a circuit because of heat can be determined by the formula _____.
P = I^2 x R
Autotransformers use separate windings for the primary and secondary.
True
Type _____ insulated conductors shall not be subject to the ampacity adjustment provisions of 310.15(B)(3)(c).
XHHW-2 310.15(B)(3)(c) Ex
Bonded 15 kW or smaller portable generators shall be provided with GFCI protection on all 125V, _____ receptacle outlets.
a and b 445.20(B)
EMT shall not be used where _____.
a and c 358.12(1) and (2)
An attachment plug and receptacle can serve as the disconnecting means for a single-phase room air conditioner rated 250V or less if _____.
a or b 440.63(1) and (2)
Cable tray systems shall not be used _____.
a or b 392.12
Service equipment labeling in other than dwelling units shall not be required if an arc-flash label is applied in accordance with _____ industry practice.
acceptable (110.16(B) Ex)
Where more than two Type NM cables are installed through the same opening in wood framing that is to be sealed with thermal insulation, caulk, or sealing foam, the allowable ampacity of each conductor shall be _____.
adjusted in accordance with Table 310.15(B)(3)(a) 334.80
Conductor resistance is determined by the _____.
all of these
Which of the following statements about a 30 hp, 460V, three-phase synchronous motor and a 10 hp, 460V, three-phase motor is(are) true?
all of these
Grounding electrode conductors of the wire type shall be _____.
any of these 250.62
Insulated conductors used in wet locations shall be _____.
any of these 310.10(C)(1), (2), and (3)
The circuit conductors between the final overcurrent device protecting the circuit and the outlet(s) are known as "_____ conductors."
branch-circuit (100)
The NEC defines a(n) "_____" as a structure that stands alone or that is separated from adjoining structures by fire walls.
building (100)
Short sections of metal enclosures or raceways used to provide support or protection of _____ from physical damage shall not be required to be connected to the equipment grounding conductor.
cable assemblies 250.86 Ex 2
A device that provides a means to connect intersystem bonding conductors for _____ systems to the grounding electrode system is an intersystem bonding termination.
communications (100 Intersystem Bonding Termination)
Direct-current motors use brushes with springs to hold them in contact with a(n) _____.
commutator
LFMC shall not be required to be secured or supported where fished between access points through _____ spaces in finished buildings or struc-tures and supporting is impractical.
concealed 350.30(A) Ex 1
Unbroken lengths of electric nonmetallic tubing shall not be required to be secured where fished between access points for _____ work in finished buildings or structures and securing is impractical.
concealed 362.30(A) Ex 3
Phase differences are expressed in _____.
degrees
The insulating material between the surface plates of a capacitor is called the "_____."
dielectric
General-use _____ switches shall be used only to control permanently installed incandescent luminaires unless listed for control of other loads and installed accordingly.
dimmer 404.14(E)
Type MC Cable listed for _____ is permitted to be installed underground under a building without installation in a raceway.
direct burial 300.5(C) Ex 2
A(n) _____ motor has a wide speed range.
direct-current
The advantage of alternating current over direct current is that alternating current provides for _____.
ease of voltage variation
Motor efficiency can be determined by which of the following formulas?
hp x 746W/W Input
Transformers are rated in _____.
kVA
To change a percent value to a decimal or whole number, drop the percentage sign and move the decimal point two places to the _____.
left
Meter sockets supplied by and under the exclusive control of an electric utility shall not be required to be _____ in accordance with 230.66.
listed 230.66 Ex
Where installed to reduce electrical noise for electronic equipment on the grounding circuit, a metal raceway can terminate to a(n) _____ nonmetallic fitting(s) or spacer on the electronic equipment. The metal raceway shall be supplemented by an internal insulated equipment grounding conductor.
listed 250.96(B) and 300.10 Ex 2
Where Type NM cable passes through factory or field openings in metal members, it shall be protected by _____ bushings or _____ grommets that cover metal edges.
listed 300.4(B)(1)
Type AC cable and associated fittings shall be _____.
listed 320.6
Type UF cable and associated fittings shall be _____.
listed 340.6
labeledFor the purposes of 350.30, _____ LFMC fittings shall be permitted as a means of securement and support.
listed 350.30(A) Ex 4
Cable ties used to secure and support LFNC shall be _____ as suitable for the application and for securing and supporting.
listed 356.30(1)
Service metal raceways and metal clad cables are considered effectively bonded when using threadless couplings and connectors that are _____.
made up tight 250.92(B)(3)
The connection between the grounded circuit conductor and the equipment grounding conductor at the service is accomplished by installing a(n) _____ bonding jumper.
main (100 Bonding Jumper, Main)
For a grounded system, an unspliced _____ shall be used to connect the equipment grounding conductor(s) and the service disconnect enclosure to the grounded conductor of the system within the enclosure for each service disconnect.
main bonding jumper 250.24(B)
Supplementary overcurrent protection _____.
may be used to protect internal circuits of equipment 240.10
A neutral conductor is the conductor connected to the _____ of a system that's intended to carry neutral current under normal conditions.
neutral point
When conductors enter an enclosure opposite a removable cover, the distance from where the conductors enter to the removable cover must not be less than _____ times the largest raceway.
none of these
Effective January 1, 2020, electronic lighting control switches shall not introduce current on the equipment grounding conductor during _____ operation.
normal 404.22
Transformers with ventilating openings shall be installed so that the ventilating openings are _____.
not blocked by walls or obstructions 450.9
A building or structure shall be supplied by a maximum of _____ feeder(s) or branch circuit(s), unless specifically permitted otherwise.
one 225.30
Where the box is mounted on the surface, direct metal to metal contact between the device yoke and the box shall be permitted to ground the receptacle to the box if at least _____ of the insulating washers of the receptacle is (are) removed.
one 250.146(A)
A box shall not be required where cables or conductors from cable trays are installed in bushed conduit and tubing used as support or for protec-tion against _____.
physical damage 392.46
Where mating dissimilar metals, antioxidant material suitable for the battery connection shall be used where _____ by the battery manufacturer.
recommended 480.4(A)
A wattmeter is connected in _____ in the circuit.
series-parallel
Overhead system service-entrance conductors are the service conductors between the terminals of the _____ and a point where they are joined by a tap or splice to the service drop or overhead service conductors.
service equipment (100 Service-Entrance Conductors, Overhead System)
Bends made in interlocked or corrugated sheath Type MC cable shall have a radius of at least _____ times the external diameter of the metallic sheath.
seven 330.24(B)
Each cable entering a cutout box _____.
shall be secured to the cutout box 312.5(C)
Duct heater controller equipment shall have a disconnecting means installed within _____ the controller except as allowed by 424.19(A).
sight from 424.65
There shall be no more than _____ disconnects installed for each service or for each set of service entrance conductors as permitted in 230.2 and 230.40.
six 230.71(A)
Kirchoff's Current Law states that in a series circuit, the current is _____ through the transformer, the conductors, and the appliance.
the same
The maximum length of a feeder tap conductor in a high bay manufacturing building over 35 ft high shall be _____ ft.
100 240.21(B)(4)(2)
The primary winding of a transformer operates at 240V, the secondary at 12V, and the load consists of two 100W lamps. What's the load on the secondary winding if the transformer winding is rated 92 percent efficient?
200 VA
What's the volume (in cubic inches) of a 4 x 4 x 1.50 in. box?
24 cu in.
How many 20A, 120V circuits are required for fifty, 100W luminaires that have a power factor of 90 percent (noncontinuous load)?
3 circuits
A vertical run of 4/0 AWG copper shall be supported at intervals not exceeding _____.
80 ft 300.19(A) and Table 300.19(A)
If the circuit's overcurrent device exceeds _____, the conductor ampacity shall have a rating not less than the rating of the overcurrent device.
800A 240.4(C)
Type MC cable can be unsupported and unsecured where the cable is _____.
A or C 330.30(D)(1) and (2)
The standard ampere ratings for fuses includes _____.
ALL OF THESE 1A, 6A, 601A 240.6(A)
The number and size of conductors permitted in a raceway is limited to _____.
ALL OF THESE 300.17
Metal raceways shall not be _____ by welding to the raceway.
ALL OF THESE 300.18(B)
Conductors in ferrous metal raceways or enclosures shall be arranged so as to avoid heating the surrounding ferrous metal by alternating-current induction. To accomplish this, the _____ conductor(s) shall be grouped together.
ALL OF THESE 300.20(A)
Nonmetallic boxes can be used with _____.
ALL OF THESE 314.3
Equipment such as _____ shall be considered appliances, and the provisions of Article 422 apply in addition to those of Article 440.
ALL OF THESE 440.3(C)
For the purposes of 210.71, examples of rooms that are not meeting rooms include _____.
ALL OF THESE auditoriums, schoolrooms, coffee shops 210.71(A) Note 2
A communications raceway is an enclosed channel of nonmetallic materials designed for holding communications wires and cables; optical fiber cables; data cables associated with information technology and communications equipment; Class 2, Class 3, and Type PLTC cables; and power-limited fire alarm cables in _____ applications.
ALL OF THESE general-purpose, plenum, riser (100 Communications Raceway)
A common practical use of induction is for _____.
ALL OF THESE generators, transformers, motors
Type UF cable shall not be used in _____.
ALL OF THESE motion picture studios, storage battery rooms, hoistways 340.12(4), (5), and (6)
The output voltage of a generator depends upon the _____.
ALL OF THESE number of turns of wire, speed at which the coil rotates, strength of the magnetic field
Metal water piping system(s) shall be bonded to the _____, to one or more grounding electrodes used, if the grounding electrode conductor or bonding jumper to the grounding electrode is of sufficient size.
ANY OF THESE 250.104(A)(1)(1), (2), (3), and (4)
Tap connections to a common grounding electrode conductor for multiple separately derived systems shall be made at an accessible location by _____.
ANY OF THESE 250.30(A)(6)(c)(1), (2), and (3)
The normally noncurrent carrying metal parts of service equipment, such as service _____, shall be bonded together.
ANY OF THESE 250.92(A)(1) and (2)
Connection of conductors to terminal parts shall ensure a thoroughly good connection without damaging the conductors and shall be made by means of _____.
ANY OF THESE splices to flexible leads, solder lugs, pressure connectors (110.14(A))
A snap switch with an integral nonmetallic enclosure complying with 300.15(E) is required to be connected to an equipment grounding conductor.
False 404.9(B) Ex 3
Which winding of a current transformer (CT) carries more current?
The primary winding.
To determine the resistance of each resistive element in the circuit, use the formula R = E^2/VA. E is the rated voltage of the resistance, and VA is the rated power of the resistor.
True
When electrons move, the magnetic fields of the individual electrons combine to produce an overall magnetic field. The greater the current flow, the greater the overall magnetic field around the conductor.
True
When equipment grounding conductors are installed in a raceway, the actual area of the conductor must be used when calculating raceway fill.
True
Some cleaning and lubricating compounds can cause severe deterioration of many plastic materials used for insulating and structural applications in equipment.
True (110.11 Note 2)
GFCI protection shall be provided for all 15A and 20A, 125V, single phase receptacles in dwelling unit unfinished portions or areas of basements not intended as habitable rooms.
True 210.8(A)(5)
One set of service entrance conductors connected to the supply side of the normal service disconnecting means shall be permitted to supply standby power systems, fire pump equipment, and fire and sprinkler alarms covered by 230.82(5).
True 230.40 Ex 5
When calculating box fill, each space within a box installed with a barrier shall be calculated separately.
True 314.16(B)
Trade size 1 IMC run straight with threaded couplings shall be supported at intervals not exceeding 12 ft.
True 342.30(B)(2) and Table 344.30(B)(2)
Running threads shall not be used on IMC for connection at couplings.
True 342.42(B)
Galvanized steel and stainless steel EMT, elbows, couplings, and fittings can be installed in concrete, in direct contact with the earth, or in areas subject to severe corrosive influences where _____.
a and b 358.10(B)(1)
Power distribution blocks installed in metal wireways shall _____.
a and b 376.56(B)(3) and (4)
Cable trays shall be _____ except as permitted by 392.18(D).
a and b 392.18(E)
Electric space-heating cables shall not be installed _____.
a and b 424.38(B)(6) and (7)
Impedance is present in _____ type circuit(s).
alternating-current
Joints between PVC conduit, couplings, fittings, and boxes shall be made by _____.
an approved method 352.48
Joints between lengths of ENT, couplings, fittings, and boxes shall be made by _____.
an approved method 362.48
Openings in cabinets, cutout boxes, and meter socket enclosures through which conductors enter shall be _____.
closed in an approved manner 312.5(A)
Extreme _____ may cause PVC conduit to become brittle, and therefore more susceptible to damage from physical contact.
cold 352.10 Note
A separate portion of a raceway system that provides access through a removable cover(s) to the interior of the system defines the term "_____."
conduit body (100)
A(n) _____ type of electric motor tends to "run away" if it isn't always connected to its load.
direct-current series
When calculating a feeder or service load for existing installations, if the maximum demand data for a 1 year period is not available, the calculated load shall be permitted to be based on the maximum demand (the _____ kilowatts reached and maintained for a 15 minute interval) continuously recorded over a minimum 30 day period using a recording ammeter or power meter connected to the highest loaded phase of the feeder or service, based on the initial loading at the start of the recording.
highest average 220.87(1) Ex
Nonautomatic is defined as requiring _____ to perform a function.
human intervention (100 Nonautomatic)
Separately derived system generators shall have the _____ conductor sized not smaller than required to carry the maximum unbalanced current as determined by 220.61.
neutral
The relationship of the number of turns of wire on the _____ as compared to the number of turns on the _____ is called "turns ratio."
primary, secondary
The identification of _____ to which a grounded conductor is to be connected shall be substantially white in color.
terminals 200.9
All cut ends of LFMC conduit shall be _____ inside and outside to remove rough edges.
trimmed 350.28
The _____ induction motor is used only in special applications and is always operated on three-phase alternating-current power.
wound-rotor
What's the cost of power consumed per month (at $0.10 per kWh) for a 10-ohm ground rod having a ground-fault voltage of 120V?
$105
What's the cross-sectional area in square inches for an 8 AWG bare solid conductor?
0.013 sq in.
What's the cross-sectional area in square inches for a 14 RHW conductor (without an outer cover)?
0.0209 sq in.
A 240V, 40A, single-phase load is located 150 ft from an existing junction box. The junction box is located 50 ft from the panelboard and is wired with 4 AWG aluminum wire. The total resistance of the two 4 AWG conductors from the panelboard to the junction box is approximately _____.
0.05 ohms
What's the primary kVA rating for a transformer winding that's 100 percent efficient if a 5A load on the secondary operates at 12V?
0.06 kVA
The approximate decimal equivalent for the fraction "4/18" is _____.
0.20
When calculations in Article 220 result in a fraction of an ampere that is less than _____, such fractions can be dropped.
0.5 220.5(B)
The primary winding of a transformer has 100 turns and the secondary winding has 10 turns. What's the current flowing through the primary winding if the current flowing through the secondary winding is 5A?
0.50A
If the neutral of the circuit in the diagram is opened, the circuit becomes one series circuit of 240V. Under this condition, the current of the circuit is _____. Tip: Determine the total resistance. See Figure.
0.58A
A 2 TW conductor is installed in a location where the ambient temperature is expected to be 102°F. The temperature correction factor for conductor ampacity in this location is _____.
0.82
What's the neutral current for a 4-wire, 120/208V circuit, where L1 = 20A, L2 = 20A, and L3 = 20A?
0A
Liquidtight flexible metal conduit shall be securely fastened by a means approved by the authority having jurisdiction within _____ of termination.
1 ft. / 12i in. 350.30(A)
One kVA is equal to _____.
1,000 VA
Ground fault protection of equipment shall be provided for solidly grounded wye electrical systems of more than 150 volts to ground, but not exceeding 1,000V phase to phase for each individual device used as a building or structure main disconnecting means rated _____ or more, unless specifically exempted.
1,000A 240.13
A secondary tie of a transformer is a circuit operating at _____, nominal, or less, between phases that connects two power sources or power-supply points.
1,000v 450.6
What's the true power of a 12A load rated 120V, with a power factor of 80 percent?
1,150W 12x0.8x120
In other than dwelling units, in addition to requirements for field or factory marking of equipment to warn qualified persons of potential electric arc-flash hazards, a permanent label shall be field or factory applied to service equipment rated _____ or more.
1,200A (110.16(B))
The input VA of a 1 hp (16A), 115V, single-phase motor is _____.
1,840 VA
Where service entrance conductors are installed in parallel in two or more raceways or cables, the size of the grounded conductor in each raceway or cable shall be based on the total circular mil area of the parallel ungrounded service entrance conductors in the raceway or cable, sized in accordance with 250.24(C)(1), but not smaller than _____ AWG.
1/0 250.24(C)(2)
The minimum point of attachment of overhead service conductors to a building shall not be less than _____ ft above finished grade.
10 230.26
One or more metal in ground support structure(s) in direct contact with the earth vertically for _____ ft or more, with or without concrete encasement is permitted to be a grounding electrode in accordance with 250.52.
10 250.52(A)(2)
For interior installations of Type SE cable with ungrounded conductor sizes _____ AWG and smaller, where installed in thermal insulation, the ampacity shall be in accordance with the conductor's temperature rating.
10 338.10(B)(4)(a)
Feeder grounded conductors shall be permitted to be sized at _____ percent of the continuous and noncontinuous load where a portion of the feeder is connected at both its supply and load ends to separately installed pressure connections.
100 215.2(A)(1)(a) Ex 2
What is the minimum cover requirement for Type UF cable supplying power to a 120V, 15A GFCI-protected circuit outdoors under a driveway of a one-family dwelling?
12 IN. 300.5(A) and Table 300.5 Column 4
Branch-circuit conductors supplying a single air-conditioner motor-compressor shall have an ampacity not less than _____ percent of either the motor-compressor rated-load current or the branch-circuit selection current, whichever is greater.
125 440.32
What's the required feeder short-circuit ground-fault protection (inverse time circuit breaker) for two 40A motors, one 20A (15-minute duty cycle) motor, and one 7A motor?
150A
The ampacity of 15 current-carrying 10 RHW aluminum conductors in a raceway in an ambient temperature of 76°F is _____.
15A
What's the maximum size overcurrent protection device for a 2,500W, 240V water heater?
15A
Article 411 covers lighting systems and their associated components operating at no more than _____ ac or _____ dc where wet contact is likely to occur
15V, 30V 411.1
The minimum vertical dimension for the junction box shown in the Figure is _____.
16 in.
What's the cross-sectional area of a 4 in. x 4 in. wireway?
16 sq in.
If a set of 120/240V overhead feeder conductors terminates at a through the roof raceway or approved support, with not more than 6 ft of these conductors, 4 ft horizontally, passing over the roof overhang, the minimum clearance above the roof for these conductors is not less than _____.
18 in.
The opening of the ungrounded or neutral conductor of a _____ circuit during the replacement of a device doesn't cause a safety hazard, so the pigtailing of these conductors isn't required.
2-wire
Article 411 covers lighting systems and their associated components operating at no more than _____ ac or _____ dc.
30V, 60V 411.1
The input power for a 20 kW load will be approximately _____ if it operates at an efficiency level of 65 percent.
31 kW
The ampacity for each of nine current-carrying 10 THW conductors installed in a 20-in. long raceway is _____.
35A
Where raceways contain insulated circuit conductors _____ AWG and larger, the conductors shall be protected from abrasion during and after installation by a fitting that provides a smooth, rounded insulating surface.
4 300.4(G)
If a trade size 3 raceway entry (250 kcmil) is in the wall opposite a removable cover, the distance from that wall to the cover must not be less than _____.
4 1/2 in.
An existing junction box is located 65 ft from the panelboard and contains 4 AWG aluminum conductors. What size copper conductors can be used to extend this circuit 85 ft and supply a 50A, 208V load? Note: Apply the NEC recommended voltage-drop limits.
4 AWG
If Bell 2 consumes 12W of power when supplied by two 12V batteries (connected in series), the resistance of this bell is _____. See Figure.
48 ohms
A vertically mounted luminaire weighing not more than _____ lb can be supported to a device box or plaster ring with no fewer than two No. 6 or larger screws.
6 314.27(A)(1) Ex
When Type AC cable is run across the top of a floor joist in an attic without permanent ladders or stairs, guard strips within _____ ft of the scuttle hole or attic entrance shall protect the cable.
6 320.23(A)
Type MC cable installed horizontally through wooden or metal framing members are considered secured and supported where such support does not exceed _____-ft intervals.
6 330.30(C)
Closet storage space is defined as a volume bounded by the sides and back closet walls extending from the closet floor vertically to a height of _____ ft or the highest clothes-hanging rod at a horizontal distance of 2 ft from the sides and back of the closet walls.
6 410.2 Closet Storage Space
What size branch-circuit conductors are required for a 25 hp, three-phase, 460V motor with terminals rated 60°C?
6 AWG
When a raceway doesn't exceed 24 in. in length, the raceway is permitted to be filled to _____ percent of its cross-sectional area.
60
If cables meeting the requirements in 310.15(B)(3)(4)a through c with more than 20 current-carrying conductors are installed longer than 24 in. without maintaining spacing, are stacked, or are supported on bridle rings, a _____ percent adjustment factor shall be applied.
60 310.15(B)(3)(a)(4) Ex
Where conductors are installed in raceways or cables exposed to direct sunlight on or above rooftops, a temperature adder of _____º F shall be added to the outdoor temperature where the conduits are less than 7/8 in. from the rooftop.
60 310.15(B)(3)(c)
How many 6 RHH conductors (without outer cover) can be installed in trade size 1 1/4 electrical nonmetallic tubing?
8 conductors
There are three motors; one 5 hp, 230V, single-phase motor with a service factor of 1.20, and two 1 1/2 hp, 120V, single-phase motors. Using an inverse time breaker, the 3-wire feeder conductor protection device after balancing all three motors will be _____.
90A
What size wireway is required for three 400 kcmil THHN, one 250 kcmil THHN, four 4/0 THHN conductors, and three 8 THHN conductors?
A 6 in. x 6 in. wireway.
At Type AC cable terminations, a(n) _____ shall be provided.
A and B fitting (or box design) that protects the conductors from abrasion, insulating bushing between the conductors and the cable armor 320.40
Type MC cable shall be supported and secured by staples; cable ties _____ for securement and support; straps, hangers, or similar fittings; or other approved means designed and installed so as not to damage the cable.
A and B listed, identified 330.30(A)
Type SE cable shall be permitted to be used as _____ in wiring systems where all of the circuit conductors of the cable are of the thermoset or thermoplastic type.
A or B branch circuits feeders 338.10(B)(1)
Conductors installed in nonmetallic raceways run underground shall be permitted to be arranged as _____ installations. The raceways shall be installed in close proximity, and the conductors shall comply with the provisions of 300.20(B).
ALL OF THESE 300.3(B)(1) Ex
Conductors smaller than 1/0 AWG can be connected in parallel to supply control power, provided _____.
ALL OF THESE 310.10(H)(1) Ex 1(a), (b), and (c)
Where correction or adjustment factors are required by 310.15(B)(2) or (3), for single-phase feeder conductors installed for _____ dwellings, they shall be permitted to be applied to the ampacity associated with the temperature rating of the conductor.
ALL OF THESE 310.15(B)(7)
Cabinets, cutout boxes, and meter socket enclosures can be used for conductors feeding through, spliced, or tapping off to other enclosures, switches, or overcurrent devices where _____.
ALL OF THESE 312.8(A)(1), (2), and (3)
Armored cable shall not be installed _____.
ALL OF THESE 320.12(1), (2), and (4)
Type MC cable shall not be used under which of the following conditions?
ALL OF THESE 330.12
Type TC cable can be used _____.
ALL OF THESE 336.10(1), (2), and (5)
Type UF cable shall not be used _____.
ALL OF THESE 340.12(7), (8), and (9)
The use of LFMC shall be permitted for _____.
ALL OF THESE 350.10(3)
For liquidtight flexible metal conduit, if flexibility is necessary after installation, unsecured lengths from the last point the raceway is securely fastened shall not exceed _____.
ALL OF THESE 350.30(A) Ex 2(1), (2), and (3)
PVC conduit shall not be used _____, unless specifically permitted.
ALL OF THESE 352.12(A), (B), and (C)
A multioutlet assembly shall not be installed _____.
ALL OF THESE 380.12(2), (4), and (5)
Cable trays can be used as a support system for _____.
ALL OF THESE 392.10
An attachment plug and receptacle can serve as the disconnecting means for cord-connected _____.
ALL OF THESE 440.13
Wiring methods permitted for service entrance conductors include _____.
ALL OF THESE rigid metal conduit, electrical metallic tubing, PVC conduit
A waveform represents _____.
ALL OF THESE the magnitude and direction of current or voltage, how output voltage can vary with the generator armature, how current or voltage can vary with time
The intersystem bonding termination shall _____.
ALL OF THESE 250.94(A)(4), (5), and (6)
An electrical circuit consists of the _____.
ALL OF THESE conductors, power source, load
The total current of the circuit shown in the Figure can be read on _____.
ALL OF THESE, Ammeter 1, Ammeter 2, Ammeter 3
The power consumed in a series circuit is _____.
ALL OF THESE, determined by the formula PT = E x I, determined by the formula PT = I2 x RT, the sum of the power consumed by each load
A series circuit has four 40-ohm resistors and the power supply is 120V. The voltage drop of each resistor will be _____.
ALL OF THESE, the same across each resistor, 30V, one-quarter of the source voltage
Power distribution blocks shall be permitted in pull and junction boxes over 100 cu in. when _____.
ALL OF THSE 314.28(E)(1), (2), and (3)
Where grounded conductors of different systems are installed in the same raceway, cable, or enclosure, each neutral conductor shall be identified to distinguish the systems by _____.
ANY OF THESE 200.6(D)(1), (2), and (3)
Electrical continuity at service equipment, service raceways, and service conductor enclosures shall be ensured by _____.
ANY OF THESE 250.92(B)(1) through(4)
At existing buildings or structures, an intersystem bonding termination is not required if other acceptable means of bonding exists. An external accessible means for bonding communications systems together can be by the use of a(n) _____.
ANY OF THESE 250.94(A) Ex
Type AC cable shall be supported and secured by _____.
ANY OF THESE 320.30(A)
IMC can be installed in or under cinder fill subject to permanent moisture _____.
ANY OF THESE 342.10(C)
The rules of _____, as applicable, shall apply to air-conditioning and refrigerating equipment that does not incorporate a hermetic refrigerant motor-compressor.
ANY OF THESE 440.3(B)
Where a premises wiring system contains feeders supplied from more than one nominal voltage system, each ungrounded conductor of a feeder shall be identified by phase or line and system by _____, or other approved means.
ANY OF THESE color coding, marking tape, tagging 215.12(C)(1)(a)
If the use of multiple grounding connections results in objectionable current and the requirements of 250.4(A)(5) or (B)(4) are met, it shall be permitted to _____.
ANY OF THESE discontinue one or more but not all of such grounding connections, change the locations of the grounding connections, interrupt the continuity of the conductor or conductive path causing the objectionable current 250.6(B)(1), (2), and (3)
Conductors of ac and dc circuits, rated 1,000V or less, shall be permitted to occupy the same _____ provided that all conductors have an insulation rating equal to the maximum voltage applied to any conductor.
ANY OF THESE enclosure, raceway, cable 300.3(C)(1)
Conductive optical fiber cables contain noncurrent-carrying conductive members such as metallic _____.
ANY OF THESE armor or sheath, strength members, vapor barriers (100 Conductive Optical Fiber Cable)
Equipment or materials to which has been attached a(n) _____ of an FEB indicating the equipment or materials were evaluated and found to comply with requirements as described in an accompanying field evaluation report is known as "field labeled (as applied to evaluated products)."
ANY OF THESE, label, symbol, other identifying mark (100Field Labeled (as applied to evaluated products))
_____ is a nonferrous, nonmagnetic metal that has no heating due to hysteresis heating.
Aluminum 300.20(B) Note
_____ connectors shall not be concealed when used in installations of LFMC.
Angle 350.42
When all the conductors are the same size (total cross-sectional area including insulation), the number of conductors permitted in a raceway can be determined by simply looking at the Tables in _____ of the NEC.
Annex C
If three capacitors are to be connected together, which connection will provide the highest capacitance?
Connect all three in parallel.
The 120V, 20A branch circuit required for a garage is not permitted to supply readily accessible outdoor receptacle outlets.
False 210.11(C)(4) Ex
A Type 2 surge protective device is permitted to be connected on either the line or load side of the service equipment.
False 285.24(A)
Where used, the surge protective device shall be connected to the grounded conductor of the circuit.
False 285.4
When installed under metal-corrugated sheet roof decking, cables, raceways, and enclosures are permitted in concealed locations of met-al-corrugated sheet decking type roofing if they are at least 2 in. away from a structural support member.
False 300.4(E)
Type NM cable can be installed as open runs in dropped or suspended ceilings in other than one- and two-family and multifamily dwellings.
False 334.12(A)(2)
Type UF cable can be used for service conductors.
False 340.12(1)
Type UF cable can be used in commercial garages.
False 340.12(2)
ENT shall be permitted for direct earth burial unless used with fittings listed for this purpose.
False 362.12(4)
Flexible cord sets and power-supply cords shall not be permitted above suspended or dropped ceilings even if contained within an enclosure for use in "other spaces used for environmental air."
False 400.12 Ex to (5)
The label required for switchboards, switchgear, and panelboards [408.4(B)] shall be permanently affixed, of sufficient durability to withstand the environment involved, and handwritten.
False 408.4(B)
A motor controller shall open all conductors to the motor where not used as a disconnecting means.
False 430.84
If the 15 kW or smaller portable generator was manufactured or remanufactured prior to _____, listed cord sets or devices incorporating listed GFCI protection for personnel identified for portable use shall be permitted.
January 1, 2015 445.20(B) Ex to (A) and (B)
What size THHN feeder conductor is required for two 40A motors, one 20A (15-minute duty cycle) motor, and one 7A motor?
1 AWG
Motors with a nameplate service factor (SF) rating of 1.15 or more must have the overload protection device sized at no more than _____ percent of the motor nameplate current rating.
125
If the peak value of an alternating-current system is 50A, the RMS value will be approximately _____.
35A 50/sqrt2
What size transformer is required for fifty, 100W luminaires that have a power factor of 90 percent (noncontinuous load)?
6 kVA
When Type NM cable is used with nonmetallic boxes not larger than 2 1/4 x 4 in., securing the cable to the box shall not be required if the cable is fastened within _____ in. of that box.
8 314.17(C) Ex
Factors that determine the capacitance of a capacitor are the _____.
ALL OF THESE dielectric between the plates, surface area of the plates, distance between the plates
A separate water piping bonding jumper shall be required if the metal frame of a building or structure is used as the grounding electrode for a separately derived system and is bonded to the metal water piping in the area served by the separately derived system.
False 250.104(D)(1) Ex 2
Conductor resistance is directly proportional to the conductor's length and cross-sectional area.
False
The building or structure grounding electrode system shall be used as the _____ electrode for the separately derived system.
Grounding 250.30(A)(4)
An overload is the same as a short circuit or ground fault.
False (100 Overload)
For grounded systems, normally noncurrent carrying conductive materials enclosing electrical conductors or equipment shall be connected to earth so as to limit the voltage to ground on these materials.
True 250.4(A)(2)
Fixture wires shall not be used for branch-circuit wiring, except as permitted in other articles of the Code.
True 402.12
If an appliance of more than 1/8 hp is provided with a unit switch that complies with 422.34(A), (B), (C), or (D), the switch or circuit breaker serving as the other disconnecting means shall be permitted to be out of sight from the appliance.
True 422.31(C) Ex
Article 440 applies to electric motor-driven air-conditioning and refrigerating equipment that has a hermetic refrigerant motor-compressor.
True 440.1
Article 445 contains installation and other requirements for generators.
True 445.1
GFCI protection for 15 kW or smaller portable generators shall not be required where the 125V receptacle outlets(s) is interlocked such that it is not available for use when any 125/250V receptacle(s) is in use.
True 445.20(A) Ex
Section 590.6(A)(3) provides the GFCI requirements for 15 kW or smaller portable generators used for temporary electric power and lighting.
True 445.20(B) Note
Metallic structures for the support of storage batteries shall be provided with nonconducting support members for the cells, or shall be constructed with a continuous insulating material and paint alone shall not be considered as an insulating material.
True 480.9
Ungrounded means not connected to ground or to a conductive body that extends the ground connection.
True (100 Ungrounded
The disconnecting means for air-conditioning and refrigerating equipment shall be _____ from the air-conditioning or refrigerating equipment.
a AND b 440.14
Feeder conductors that supply several motors must have an ampacity of not less than _____.
a and b
Series circuits are often used for _____ applications.
a and b
If the ungrounded conductors of a multiwire branch circuit aren't terminated to different phases, this can cause the neutral current to exceed the neutral conductor's ampacity.
True
In a parallel circuit, the voltage drop across each resistance is equal to the sum of the voltage drops of each of the resistors in parallel.
True
In an alternating-current induction motor, the stator produces a rotating magnetic field that induces current in the rotor windings. The rotor current generates a magnetic field in opposition to the magnetic field of the stator, thereby causing the rotor to turn.
True
The 3 VA per square foot general lighting load for dwelling units includes general use receptacles and lighting outlets.
True 220.14(J)
Two family dwellings, multifamily dwellings, and multiple occupancy buildings shall be permitted to have one set of service entrance conductors to supply branch circuits for public or common areas.
True 230.40 Ex 4
A service disconnecting means shall not be installed in bathrooms.
True 230.70(A)(2)
Cables or raceways installed using directional boring equipment shall be _____ for this purpose.
approved 300.5(K)
Where independent support wires of a suspended ceiling assembly are used to support raceways, cable assemblies, or boxes above a ceiling, they shall be secured at _____ end(s).
both 300.11(B)
Wasteful circulating _____ in the iron core cause(s) the core to heat up without any useful purpose.
eddy currents
Where the junction box contains a power distribution block, and it has conductors that do not terminate on the power distribution block(s), the through conductors shall be arranged so the power distribution block terminals are _____ following installation.
unobstructed 314.28(E)(5)
Alternating current is primarily used because it can be transmitted inexpensively due to the ease of transforming to high-transmission voltage and then transforming this voltage back to low-distribution voltage.
True
Apparent power (VA) is used for sizing circuits and equipment. Because the VA of the load is greater than the watts of the load, fewer loads can be supplied by each branch circuit.
True
Once a motor begins turning, the rotor windings are increasingly cut by the stationary magnetic field, resulting in an increasing counter-electromotive force.
True
The actual motor current depends upon the load on the motor and the operating voltage at the motor terminals.
True
The advantage of the reciprocal method is that the formula can be used for as many resistances as the parallel circuit contains.
True
The alternating-current conductor resistances listed in Chapter 9, Table 9 of the NEC are different for copper and aluminum and for nonmagnetic and magnetic raceways.
True
The best conductors, in order of their conductivity, are gold, silver, copper, and aluminum.
True
The leakage of electromagnetic flux lines between the primary and secondary windings of a transformer represents wasted energy.
True
The major advantage of alternating current over direct current is the ease of voltage regulation by the use of a transformer.
True
The motor FLA rating is used when sizing motor conductors or circuit protection.
True
The neutral conductor of a 3-wire, 120/240V, single-phase circuit only carries the unbalanced current when the circuit isn't balanced.
True
The neutral conductor of a 4-wire, 120/208V or 277/480V, three-phase system has neutral current flow when the ungrounded conductors are equally loaded.
True
The primary electromagnetic field induces a voltage in the secondary. As the secondary current flows, it produces an electromagnetic field that reduces the strength of the primary flux lines. This results in an increase in primary current.
True
The resistance of a conductor is directly proportional to its length.
True
The term "Phase" is used to indicate the time or degree relationship between two waveforms, such as voltage-to-current or voltage-to-voltage.
True
The true power of an alternating-current circuit equals volts times amperes.
True
To reverse a direct-current series motor, we may simply reverse the supply (power) leads.
True
Voltage induced in the secondary winding of a transformer is dependent on the number of secondary turns as compared to the number of primary turns.
True
The minimum height of working spaces about electrical equipment, switchboards, panelboards, or motor control centers operating at 1,000V, nominal, or less and likely to require examination, adjustment, servicing, or maintenance while energized shall be 6 1/2 ft or the height of the equipment, whichever is greater, except for service equipment or panelboards in existing dwelling units that do not exceed 200A.
True (110.26(A)(3) and 110.26(A)(3) Ex 1)
Where a remote control device actuates the service disconnecting means, the service disconnecting means shall still be at a readily accessible location either outside the building or structure, or nearest the point of entry of the service conductors.
True 230.70(A)(3)
Metal gas piping shall be considered bonded by the equipment grounding conductor for the circuit that is likely to energize the piping system.
True 250.104(B)(1)
Exposed structural metal interconnected to form a metal building frame that is not intentionally grounded or bonded and is likely to become energized shall be considered bonded when one or more grounding electrodes are used, if the grounding electrode conductor or bonding jumper to the grounding electrode is of sufficient size.
True 250.104(B)(5)
Alternating current circuits of less than 50V shall be grounded if supplied by a transformer whose supply system exceeds 150 volts to ground.
True 250.20(A)(1)
A grounding electrode shall be required if a building or structure is supplied by a feeder.
True 250.32(A)
Where more than one concrete encased electrode is present at a building or structure, it shall be permitted to connect to only one of them.
True 250.52(A)(3)
The grounding of electrical systems, circuit conductors, surge arresters, surge protective devices, and conductive normally noncurrent carrying metal parts of equipment shall be installed and arranged in a manner that will prevent objectionable current.
True 250.6(A)
Temporary currents resulting from abnormal conditions, such as ground faults, are not considered to be objectionable currents.
True 250.6(C)
Ferrous metal raceways and enclosures for grounding electrode conductors shall be electrically continuous from the point of attachment to cabinets or equipment to the grounding electrode.
True 250.64(E)(1)
A grounding electrode conductor shall be permitted to be run to any convenient grounding electrode available in the grounding electrode system where the other electrode(s), if any, is connected by bonding jumpers that are installed in accordance with 250.53(C).
True 250.64(F)(1)
The metal structural frame of a building shall be permitted to be used as a conductor to interconnect electrodes that are part of the grounding electrode system, or as a grounding electrode conductor. Hold down bolts securing the structural steel column that are connected to a concrete encased electrode that complies with 250.52(A)(3) and is located in the support footing or foundation shall be permitted to connect the metal structural frame of a building or structure to the concrete encased grounding electrode.
True 250.68(C)(2)
Surge arrestors 1,000V or less are also known as Type 1 surge protective devices (SPDs).
True 285.1 Note
Surge protective devices shall be listed.
True 285.6
Surge protective devices shall be marked with a short circuit current rating and shall not be installed where the available fault current is in excess of that rating.
True 285.7
A box or conduit body shall not be required where cables enter or exit from conduit or tubing that is used to provide cable support or protection against physical damage.
True 300.15(C)
A box or conduit body shall not be required for splices and taps in direct-buried conductors and cables as long as the splice is made with a splicing device that is identified for the purpose.
True 300.15(G)
Prewired raceway assemblies shall be used only where specifically permitted in the NEC for the applicable wiring method.
True 300.18(A)
Direct-buried conductors or cables can be spliced or tapped without the use of splice boxes when the splice or tap is made in accordance with 110.14(B).
True 300.5(E)
In general, areas where acids and alkali chemicals are handled and stored may present corrosive conditions, particularly when wet or damp.
True 300.6(D) Note
Raceways shall be provided with expansion, expansion-deflection, or deflection fittings where necessary to compensate for thermal expansion, deflection, and contraction.
True 300.7(B)
Where conductors in parallel are run in separate raceways, the raceways shall have the same electrical characteristics.
True 310.10(H)(3)
Each current-carrying conductor of a paralleled set of conductors shall be counted as a current-carrying conductor for the purpose of applying the adjustment factors of 310.15(B)(3)(a).
True 310.15(B)(3)(a)
On a three-phase, 4-wire, wye circuit, where the major portion of the load consists of nonlinear loads, the neutral conductor shall be counted when applying 310.15(B)(3)(a) adjustment factors.
True 310.15(B)(5)(c)
The service or feeder ratings addressed by 310.15(B)(7) are based on the standard ampacity ratings from 240.6(A).
True 310.15(B)(7) Note 1
Type AC cable installed through, or parallel to, framing members shall be protected against physical damage from penetration by screws or nails.
True 320.17
Type NM cable shall closely follow the surface of the building finish or running boards when run exposed.
True 334.15(A)
Type TC cable can be used in one- and two-family dwelling units.
True 336.10(9)
Type TC-ER cable used for interior wiring in one- and two-family dwelling units that is suitable for pulling through structural members is marked "TC-ER-JP."
True 336.10(9) Note 1
Where Type TC cable is installed in one- and two-family dwelling units, 725.136 provides rules for limitations on Class 2 or 3 circuits contained within the same cable with conductors of electric light, power, or Class 1 circuits.
True 336.10(9) Note 2
Type USE cable used for service laterals shall be permitted to emerge from the ground if terminated in an enclosure at an outside location and protected in accordance with 300.5(D).
True 338.12(B)(2)
Type UF cable is permitted to be used for inside wiring.
True 340.10(3)
Type UF cable shall not be used where subject to physical damage.
True 340.12(10)
Aluminum RMC shall be permitted to be installed where approved for the environment.
True 344.10(A)(3)
PVC conduit shall be permitted for exposed work where subject to physical damage if identified for such use.
True 352.10(F)
PVC conduit can support nonmetallic conduit bodies not larger than the largest trade size of an entering raceway, but the conduit bodies shall not contain devices, luminaires, or other equipment.
True 352.10(H)
When a building is supplied with a fire sprinkler system, ENT can be installed above any suspended ceiling.
True 362.10(5) Ex
Metal multioutlet assemblies can pass through a dry partition, provided no receptacle is concealed in the partition and the cover of the exposed portion of the system can be removed.
True 380.76
Cable trays shall be supported at intervals in accordance with the installation instructions.
True 392.30(A)
Article 400 covers general requirements, applications, and construction specifications for flexible cords and flexible cables.
True 400.1 Note
The disconnecting means for the controller and motor shall open all ungrounded supply conductors.
True 430.103
Motor controllers and terminals of control circuit devices shall be connected with copper conductors unless identified for use with a different conductor.
True 430.9(B)
_____ motors are fractional horsepower motors that operate equally well on alternating current and direct current and are used for vacuum cleaners, electric drills, mixers, and light household appliances.
Universal
Self-induced voltage opposes the change in current flowing in the conductor. This is called "inductive reactance" and is abbreviated _____.
XL
In dwelling units, the voltage between conductors that supply the terminals of _____ shall not exceed 120V, nominal.
a and b 210.6(A)(1) and (2)
In an area served by a separately derived system, the _____ shall be connected to the grounded conductor of the separately derived system.
a and b 250.30(A)(8)
NFPA 780, Standard for the Installation of Lightning Protection Systems provides information on the installation of _____ for lightning protection systems [250.4(A)(1)].
a and b 250.4(A)(1) Note 2
_____ shall not be used as grounding electrodes.
a and b 250.52(B)(1) and (2)
Wiring methods and cabling systems, listed for use in other spaces used for environmental air (plenums), shall be permitted to be installed in ducts specifically fabricated for environmental air-handling purposes _____.
a and b 300.22(B) Ex
The wiring space within enclosures for switches and overcurrent devices shall be permitted for other wiring and equipment subject to limitations for specific equipment as provided in _____.
a and b 312.8
The wiring space of enclosures for switches or overcurrent devices shall be permitted to contain power monitoring equipment where the _____.
a and b 312.8(B)
To prevent moisture from entering service equipment, service entrance conductors shall _____.
a and b be connected to service drop conductors below the level of the service head, have drip loops formed on the individual service entrance conductors 230.54(F)
A(n) _____ shall be considered equivalent to an overcurrent trip unit for the purpose of providing overcurrent protection of conductors.
a and b current transformer, overcurrent relay 240.15(A)
Where used to securely fasten LFMC, cable ties shall be _____ for securement and support.
a and c 350.30(A)
Where IMC enters a box, fitting, or other enclosure, _____ shall be provided to protect the wire from abrasion unless the design of the box, fitting, or enclosure affords equivalent protection.
a bushing 342.46
Working space distances for enclosed live parts shall be measured from the _____ of equipment or apparatus, if the live parts are enclosed.
a or b (110.26(A)(1))
Electrical equipment with _____ and having low smoke and heat release properties, and associated wiring material suitable for the ambient temperature can be installed within an air-handling space (plenum).
a or b 300.22(C)(3)
Conduits or raceways through which moisture may contact live parts shall be _____ at either or both ends.
a or b 300.5(G)
Aluminum raceways, cable trays, cablebus, auxiliary gutters, cable armor, boxes, cable sheathing, cabinets, elbows, couplings, nipples, fittings, supports, and support hardware _____ shall be provided with supplementary corrosion protection.
a or b 300.6(B)
In installations within walls or ceilings constructed of wood or other combustible surface material, boxes, plaster rings, extension rings, or listed extenders shall _____.
a or b 314.20
A snap switch that does not have means for connection to an equipment grounding conductor shall be permitted for replacement purposes only where the wiring method does not include an equipment grounding conductor and the switch is _____.
a or b 404.9(B) Ex 1
When non-grounding-type receptacles are replaced by GFCI-type receptacles where attachment to an equipment grounding conductor does not exist in the receptacle enclosure, _____ shall be marked "No Equipment Ground."
a or b 406.4(D)(2)(b)
Where attachment to an equipment grounding conductor does not exist in the receptacle enclosure, a non-grounding-type receptacle(s) shall be permitted to be replaced with a grounding-type receptacle(s) where supplied through a ground-fault circuit interrupter and _____ shall be marked "GFCI Protected" and "No Equipment Ground," visible after installation.
a or b 406.4(D)(2)(c)
Lampholders installed in damp locations shall be listed for use in _____ locations.
a or b 410.96
Disconnecting means for air-conditioning or refrigerating equipment can be installed _____ the air-conditioning or refrigerating equipment, but not on panels that are designed to allow access to the equipment, and not over the equipment nameplate.
a or b 440.14
Transformers and transformer vaults shall be readily accessible to qualified personnel for inspection and maintenance, except _____.
a or b 450.13(A) and (B)
All conductors of the same circuit shall be _____, unless otherwise specifically permitted in the Code.
a or b in the same raceway or cable, in close proximity in the same trench 300.5(I) and 300.3(B)
The common grounding electrode conductor installed for multiple separately derived systems shall be permitted to be the metal structural frame of the building or structure that complies with 250.68(C)(2) or is connected to the grounding electrode system by a conductor not smaller than _____.
a or b 250.30(A)(6)(a)(3)
When replacing a non-grounding-type receptacle where attachment to an equipment grounding conductor does not exist in the receptacle enclosure, the receptacle can use a _____.
a or c 406.4(D)(2)(a) and (b)
Metal wireways are sheet metal troughs with _____ for housing and protecting electric conductors and cable.
a or d 376.2 Metal Wireways
Cable wiring methods shall not be used as a means of support for _____.
all of these 300.11(D)
The ampacity adjustment factors of Table 310.15(B)(3)(a) do not apply to Type AC or Type MC cable without an overall outer jacket, if which of the following condition(s) is(are) met?
all of these 310.15(B)(3)(a)(4)
Type TC cable shall not be _____.
all of these 336.12(1), (2), and (3)
When the fluorescent luminaire disconnecting means for fluorescent luminaires that utilize double-ended lamps (typical fluorescent lamps) is external to the luminaire, it shall be _____.
all of these 410.130(G)(3)
_____ rated 250V or less and 60A or less, single- or 3-phase, shall be provided with GFCI protection for personnel.
all of these 422.5(A)(1), (2), and (3)
Electric space-heating cables shall not be installed _____.
all of these 424.38(B)(1), (2), and (3)
The GFCI required for appliances shall be readily accessible, listed, and located _____.
any of these 422.5(B)(1), (2), and (3)
If you measure voltage and current in an inductive or capacitive circuit and then multiply them together, you obtain the circuit's _____.
apparent power
If you multiply the voltage by the current in an inductive or capacitive circuit, the answer will be the _____ of the circuit.
apparent power
Plug fuses of the Edison base type shall be used only _____.
as a replacement in existing installations 240.51(B)
Special permission is the written consent from the _____.
authority having jurisdiction (100 Special Permission)
True power is always voltage times current for _____.
b and c
A _____, with an integral bushed opening shall be used at the end of a conduit or other raceway that terminates underground where the conductors or cables emerge as a direct burial wiring method.
b or c 300.5(H)
The rotating part of a direct-current motor or generator is called the _____.
b or c armature, rotor
Bends in PVC conduit shall _____ between pull points.
be limited to 360º 352.26
Type MC cable shall be listed and fittings used for connecting Type MC cable to boxes, cabinets, or other equipment shall _____.
be listed and identified for such use 330.6
Electrically conductive materials that are likely to _____ in ungrounded systems shall be connected together and to the supply system grounded equipment in a manner that creates a low impedance path for ground fault current that is capable of carrying the maximum fault current likely to be imposed on it.
become energized 250.4(B)(3)
Service raceways threaded into metal service equipment such as bosses (hubs) are considered to be effectively _____ to the service metal enclosure.
bonded 250.92(B)(2)
A means external to enclosures for connecting intersystem _____ conductors shall be provided at the service equipment or metering equipment enclosure and disconnecting means of buildings or structures supplied by a feeder.
bonding 250.94(A)
Metal cable trays containing only nonpower conductors (such as communications, data, and signaling conductors and cables) shall be electrically continuous through approved connections or the use of a(n) _____.
bonding jumper 392.60(A)
Raceways and cables installed into the _____ of open bottom equipment shall not be required to be mechanically secured to the equipment.
bottom 300.12 Ex 2
When a feeder supplies _____ in which equipment grounding conductors are required, the feeder shall include or provide an equipment grounding conductor.
branch circuits 215.6
Nominal battery voltage, as it relates to storage batteries, is the value of a(n) _____ of a given voltage class for convenient designation.
cell or battery 480.2 Nominal Voltage (Battery or Cell)
Conductor overload protection shall not be required where the interruption of the _____ would create a hazard, such as in a material handling magnet circuit or fire pump circuit. However, short circuit protection is required.
circuit 240.4(A)
The cross-sectional area of a conductor is commonly expressed in _____.
circular mils
Equipment and devices shall only be permitted within ducts or plenum chambers specifically fabricated to transport environmental air if necessary for their direct action upon, or sensing of, the _____.
contained air 300.22(B)
Galvanized steel, stainless steel and red brass RMC elbows, couplings, and fittings shall be permitted to be installed in concrete, in direct contact with the earth, or in areas subject to severe corrosive influences when protected by _____ approved for the condition.
corrosion protection 344.10(B)(1)
A device or utilization equipment wider than a single 2 in. device box shall have _____ volume allowances provided for each gang required for mounting.
double 314.16(B)(4)
A multioutlet assembly can be installed in _____.
dry locations 380.10
120V is the reading shown on a voltmeter. This is an indication of the _____ value of the voltage source.
effective
In straight pulls, the length of the box or conduit body shall not be less than _____ times the trade size of the largest raceway.
eight 314.28(A)(1)
An interactive inverter is an inverter intended for use in parallel with a(n) _____ to supply common loads that may deliver power to the utility.
electric utility (100)
Ferrous metal raceways and enclosures for grounding electrode conductors shall be bonded at each end of the raceway or enclosure to the grounding electrode or grounding electrode conductor to create a(n) _____ parallel path.
electrically 250.64(E)(1)
Direct-buried conductors, cables, or raceways, which are subject to movement by settlement or frost, shall be arranged to prevent damage to the _____ or to equipment connected to the raceways.
enclosed conductors 300.5(J)
Type SE cables shall be permitted to be used for branch circuits or feeders where the insulated conductors are used for circuit wiring and the uninsulated conductor is used only for _____ purposes.
equipment grounding 338.10(B)(2)
When LFMC is used to connect equipment where flexibility is necessary to minimize the transmission of vibration from equipment or for equipment requiring movement after installation, a(n) _____ conductor shall be installed.
equipment grounding 350.60
Where multimotor and combination-load equipment for air-conditioning and refrigeration is installed outdoors on a roof, a(n) _____ conductor of the wire type shall be installed in outdoor portions of metallic raceway systems that use non-threaded fittings.
equipment grounding 440.9
For a separate building or structure supplied by a separately derived system when overcurrent protection is provided where the conductors originate, the supply conductors shall contain a(n) _____.
equipment grounding conductor 250.32(B)(2)(a)
When LFNC is used, and equipment grounding is required, a separate _____ shall be installed in the conduit.
equipment grounding conductor 356.60
A grounding electrode at a separate building or structure shall be required where one multiwire branch circuit serves the building or structure.
false 250.32(A) Ex
The NEC defines a "_____" as all circuit conductors between the service equipment, the source of a separately derived system, or other power supply source, and the final branch-circuit overcurrent device.
feeder (100 Feeder)
Where raceways or cables enter above the level of uninsulated live parts of cabinets, cutout boxes, and meter socket enclosures in a wet location, a(n) _____ shall be used.
fitting listed for wet locations 312.2
ENT is composed of a material resistant to moisture and chemical atmospheres, and is _____.
flame retardant 362.2
Receptacles for built-in dishwashers and trash compactors shall be located to protect against physical damage to the _____.
flexible cord 422.16(B)(2)(4)
A device comprised of _____ or more receptacles shall be calculated at not less than 90 VA per receptacle.
four 220.14(I)
Equipment grounding conductor(s), and not more than _____ fixture wires smaller than 14 AWG shall be permitted to be omitted from the calculations where they enter the box from a domed luminaire or similar canopy and terminate within that box.
four 314.16(B)(1) Ex
A run of RMC shall not contain more than the equivalent of _____ quarter bend(s) between pull points such as conduit bodies and boxes.
four 344.26
Horizontal runs of RMC supported by openings through _____ at intervals not exceeding 10 ft and securely fastened within 3 ft of termination points shall be permitted.
framing members 344.30(B)(4)
A "_____" is a building or portion of a building in which one or more self-propelled vehicles can be kept for use, sale, storage, rental, repair, exhibition, or demonstration purposes.
garage (100)
Connected (connecting) to ground or to a conductive body that extends the ground connection is called "_____."
grounded (100 Grounded (Grounding))
A separate bonding jumper to the building structural metal shall not be required if the metal frame of a building or structure is used as the _____ for the separately derived system.
grounding electrode 250.104(D)(2) Ex 1
There are four principal determinants of conductor operating temperature, one of which is _____ generated internally in the conductor as the result of load current flow, including fundamental and harmonic currents.
heat 310.15(A)(3) Note 1
A transformer winding has a voltage turns ratio of 2:1. The current flowing through the secondary winding will be _____ the current flowing through the primary winding.
higher than
Conductor resistance to alternating-current flow is _____ the resistance to direct current.
higher than
Connectors and terminals for conductors more finely stranded than Class B and Class C, as shown in Table 10 of Chapter 9, shall be _____ for the specific conductor class or classes.
identified (110.14)
Where conduits are used as service masts, hubs shall be _____ for use with service entrance equipment.
identified 230.28(A)
Type TC cable shall be permitted to be direct buried, where _____ for such use.
identified 336.10(10)
Where exposed to the direct rays of the sun, insulated conductors and jacketed cables installed in cable trays shall be _____ as being sunlight resistant.
identified 392.10
Unused openings for circuit breakers and switches in switchboards and panelboards shall be closed using _____, or other approved means that provide protection substantially equivalent to the wall of the enclosure.
identified closures 408.7
The total opposition to current flow in an alternating-current circuit is expressed in ohms and is called "_____."
impedance
In dwelling units, all nonlocking type 125V and 250V, 15A and 20A receptacles installed _____ shall be listed as tamper resistant.
in all areas specified in 210.52 and 550.13 406.12(1)
Type 3 surge protective devices can be installed on the load side of a branch circuit overcurrent device up to the equipment served. If _____, the Type 3 SPD connection shall be a minimum 30 ft of conductor distance from the service or separately derived system disconnect.
included in the manufacturer's instructions 285.25
If the contact resistance of a connection increases and the current of the circuit (load) remains the same, then the voltage dropped across the connection will _____.
increase
The movement of electrons caused by an external magnetic field is called "_____ current," and the associated potential that's established is called "_____ voltage."
induced
Raceways shall be _____ between outlet, junction, or splicing points prior to the installation of conductors.
installed complete 300.18(A)
The NEC requires that electrical equipment be _____.
installed in a neat and workmanlike manner (110.12)
Type USE cable is not permitted for _____ wiring.
interior 338.12(B)(1)
When a permanently installed generator _____, the requirements of 250.30 shall apply.
is a separately derived system 250.35(A)
Where flexibility _____, liquidtight flexible metal conduit shall be permitted to be used as an equipment grounding conductor when installed in accordance with 250.118(6).
is not required after installation 350.60
In a circuit that has only capacitive reactance (XC), the voltage and current are said to be out-of-phase to each other because the voltage _____.
lags the current by 90°
Grommets or bushings for the protection of Type NM cable installed through or parallel to framing members shall be _____ for the purpose.
listed 334.17
Type NM cable and associated fittings shall be _____.
listed 334.6
Cable ties used to securely fasten ENT shall be _____ as suitable for the application and for securing and supporting.
listed 362.30(A)
Unbonded 15 kW or smaller portable generators with both 125V and 125/250V receptacle outlets shall have _____ GFCI protection for personnel integral to the generator or receptacle on all 125V, 15A and 20A receptacle outlets.
listed 445.20(A)
Storage batteries, other than lead-acid batteries, and battery management equipment shall be _____.
listed 480.3
Threadless couplings approved for use with IMC in wet locations shall be _____.
listed for wet locations 342.42(A)
Ferrous metal raceways, boxes, fittings, supports, and support hardware can be installed in concrete or in direct contact with the earth or other areas subject to severe corrosive influences, where _____ approved for the condition.
made of material 300.6(A)(3)
Bends in LFNC shall be made so that the conduit will not be damaged and the internal diameter of the conduit will not be effectively reduced. Bends can be made _____.
manually without auxiliary equipment 356.24
Metal raceways, cable armor, and other metal enclosures shall be _____ joined together into a continuous electric conductor so as to provide effective electrical continuity.
metallically 300.10
The purpose or use of panelboard circuits and circuit _____, including spare positions, shall be legibly identified on a circuit directory located on the face or inside of the door of a panelboard, and at each switch or circuit breaker in a switchboard or switchgear.
modifications 408.4(A)
The method of increasing a number by another number is done by using a ______.
multiplier
Each generator shall be provided with a _____ listing the manufacturer's name, the rated frequency, power factor, number of phases (if alter-nating current), and its rating in kilowatts or kilovolt-amperes.
nameplate 445.11
The conductors used to connect the surge protective device to the line or bus and to ground shall not be any longer than _____ and shall avoid unnecessary bends.
necessary 285.12
Where cables and nonmetallic raceways are installed parallel to framing members, the nearest outside surface of the cable or raceway shall be _____ the nearest edge of the framing member where nails or screws are likely to penetrate.
not less than 1 1/4 in. from 300.4(D)
Capacitive reactance is measured in _____.
ohms
Inductive reactance is measured in _____.
ohms
Where the circuit breaker handles are operated vertically, the "up" position of the handle shall be the "_____" position.
on 240.81
Overcurrent protection for conductors and equipment is provided to _____ the circuit if the current reaches a value that will cause an excessive or dangerous temperature in conductors or conductor insulation.
open 240.1 Note
A switchboard or panelboard containing an ungrounded ac electrical system is required to be legibly and permanently field marked to caution that the system is ungrounded and include the _____.
operating voltage between conductors 408.3(F)(2)
Reconditioned equipment shall be marked with the name, trademark, or other descriptive marking by which the _____ responsible for reconditioning the electrical equipment can be identified, along with the date of the reconditioning.
organization (110.21(A)(2))
An optical fiber cable is a factory assembly or field assembly of one or more optical fibers having a(n) _____ covering.
overall (100 Optical Fiber Cable)
Except as provided in 250.122(F)(2)(b) for raceway or cable tray installations, the equipment grounding conductor in each multiconductor cable shall be sized in accordance with 250.122 based on the _____.
overcurrent protective device for the feeder or branch circuit 250.122(F)(2)
Vegetation such as trees shall not be used for support of _____.
overhead conductor spans 225.26
Service conductors supplying a building or other structure shall not _____ of another building or other structure.
pass through the interior 230.3
Where two or more branch circuits supply devices or equipment on the same yoke or mounting strap, a means to disconnect simultaneously the ungrounded supply conductors shall be provided at the _____.
point where the branch circuits originate 210.7
The transformer winding that's connected to the source is called the "_____" winding and the transformer winding that's connected to the load is called the "_____."
primary, secondary
The _____ current for a hermetic refrigerant motor-compressor is the current resulting when the motor-compressor is operated at the rated load, rated voltage, and rated frequency of the equipment it serves.
rated-load 440.2 Rated-Load Current
In direct-current circuits, the only property that opposes current flow is _____.
resistance
If the two line (supply) leads of a direct-current series motor are reversed, the motor will _____.
run the same as before
As the alternating-current through a conductor increases, an expanding and collapsing electromagnetic field through the conductor induces a voltage within the conductor. This is known as "_____ voltage."
self-induced
The _____ is the necessary equipment, usually consisting of a circuit breaker(s) or switch(es) and fuse(s) and their accessories, connected to the load end of service conductors, and intended to constitute the main control and cutoff of the supply.
service equipment (100 Service Equipment)
The prospective symmetrical fault current at a nominal voltage to which an apparatus or system is able to be connected without sustaining damage exceeding defined acceptance criteria is known as the "_____."
short-circuit current rating (100 Short-Circuit Current Rating)
The additional service disconnecting means for fire pumps, emergency systems, legally required standby, or optional standby services, shall be installed remote from the one to six service disconnecting means for normal service to minimize the possibility of _____ interruption of supply.
simultaneous 230.72(B)
The expanding and collapsing magnetic field within the conductor induces a voltage in the conductors (CEMF) that repels the flowing electrons toward the surface of the conductor. This is called "_____."
skin effect
Cable _____ made and insulated by approved methods can be located within a cable tray provided they are accessible, and do not project above the side rails where the splices are subject to physical damage.
splices 392.56
A circuit breaker with a _____ voltage rating, such as 240V or 480V, can be used where the nominal voltage between any two conductors does not exceed the circuit breaker voltage rating.
straight 240.85
A listed expansion/deflection fitting or other approved means shall be used where a raceway crosses a _____ intended for expansion, contraction or deflection used in buildings, bridges, parking garages, or other structures.
structural joint 300.4(H)
Electrical installations in hollow spaces, vertical shafts, and ventilation or air-handling ducts shall be made so that the possible spread of fire or products of combustion is not _____.
substantially increased 300.21
Type NM cable on a wall of an unfinished basement installed in a listed raceway shall have a _____ installed at the point where the cable enters the raceway.
suitable insulating bushing or adapter 334.15(C)
Ground fault protection of equipment shall not be required at a feeder disconnect if ground fault protection of equipment is provided on the _____ side of the feeder and on the load side of any transformer supplying the feeder.
supply 215.10 Ex 2
A panelboard shall be protected by an overcurrent device within the panelboard, or at any point on the _____ side of the panelboard.
supply 408.36
In a(n) _____ motor, the rotor is actually locked in step with the rotating stator field and is dragged along at the speed of the rotating magnetic field.
synchronous
The resistance of a conductor is affected by temperature change. This is called the "_____."
temperature coefficient
Where required by the Code, markings or labels on all electrical equipment shall contain voltage, current, wattage, or other ratings and the marking or label shall be of sufficient durability to withstand _____.
the environment involved (110.21(A)(1))
The heating effects of 10A of alternating current as compared to 10A of direct current are _____.
the same
Where a supply side bonding jumper of the wire type is run with the derived phase conductors from the source of a separately derived system to the first disconnecting means, it shall be sized in accordance with 250.102(C), based on _____.
the size of the derived ungrounded conductors 250.30(A)(2)(a)
Luminaires identified for _____, with an integral outlet box in accordance with 410.21 shall be permitted to be used as a conductor raceway.
through-wiring 410.64(B)
A _____ is used to raise or lower voltage and it has the ability to transfer electrical energy from one system to another with no physical connection between the two systems.
transformer
Three-way and four-way switches shall be wired so that all switching is done only in the _____ circuit conductor.
ungrounded 404.2(A)
Cabinets, cutout boxes, and meter socket enclosures installed in wet locations shall be _____.
weatherproof 312.2
Flexible cord used in listed extension cord sets shall be considered protected against overcurrent when used _____.
within the extension cord's listing requirements 240.5(B)(3)
_____ describes the steps necessary to determine the effective voltage or current value.
"Root-mean-square"
A parallel circuit has three resistors. One resistor is rated 2 ohms, one is rated 3 ohms, and the other is rated 5 ohms. The total resistance of the parallel circuit is _____. Remember, the total resistance of any parallel circuit is always less than the smallest resistor.
1 ohm
The true power of a 2.10 kVA, single-phase load with a power factor of 91 percent is _____.
1.91 kW
A trade size 3 Schedule 40 PVC raceway contains seven 1 RHW conductors without outer cover. How many 2 THW conductors may be installed in this raceway with the existing conductors?
11 conductors
The ampacity of the conductors from the generator output terminals to the first distribution device(s) containing overcurrent protection shall not be less than _____ percent of the nameplate current rating of the generator.
115 445.13(A)
Type MC cable containing four or fewer conductors, sized no larger than 10 AWG, shall be secured within _____ in. of every box, cabinet, fitting, or other cable termination.
12 330.30(B)
What size THHN conductor is required to feed a 16A noncontinuous load when the conductors are in an ambient temperature of 100°F in a dry location? The circuit is protected with a 20A overcurrent protection device.
12 AWG
The minimum distance between the two trade size 2 raceways that contain the same Conductor C, as illustrated in the Figure is _____.
12 in.
Short-circuit and ground-fault protection for an individual air-conditioner motor-compressor shall not exceed _____ percent of the motor-compressor rated-load current or branch-circuit selection current, whichever is greater.
175 440.22(A)
If an inverse time breaker is used for the feeder short-circuit protection, what size protection is required for the following 460V, three-phase motors? (1) Motor 1 = 40 hp, 52 FLC; (2) Motor 2 = 20 hp, 27 FLC; (3) Motor 3 = 10 hp, 14 FLC; (4) Motor 4 = 5 hp, 7.60 FLC
175A
Receptacle outlets in or on floors shall not be counted as part of the required number of receptacle outlets for dwelling unit wall spaces, unless they are located within _____ in. of the wall.
18 210.52(A)(3)
For one-family dwellings and the individual dwelling units of two-family and multifamily dwellings, single-phase feeder conductors consisting of _____ ungrounded conductor(s) and the neutral conductor from a 208Y/120 volt system shall be permitted to be sized in accordance with 310.15(B)(7)(1) through (3).
2 310.15(B)(7)
What size copper conductors in a steel raceway can be used to replace 1/0 AWG aluminum that supplies an 110A load? Hint: Find a copper conductor with the same resistance per foot as the existing aluminum conductor. Note: We don't want to increase the circuit voltage drop.
2 AWG
How many 14 AWG conductors can be pulled through a 4 in. x 1 1/2 in. square box with a plaster ring marked 3.60 cu in.? The box already contains two duplex receptacles, five 14 AWG conductors, and two grounding conductors.
2 conductors
The apparent power of a 19.20A, 120V load is _____.
2.30 kVA
A bare 4 AWG copper conductor installed horizontally near the bottom or vertically, and within that portion of a concrete foundation or footing that is in direct contact with the earth, can be used as a grounding electrode when the conductor is at least _____ ft in length.
20 250.52(A)(3)
The sum of the cross-sectional areas of all contained conductors and cables at any cross section of a metal wireway shall not exceed _____ percent of the interior cross-sectional area of the wireway.
20 376.22(A)
A junction box contains two trade size 2 1/2 raceways on the left side and one trade size 2 1/2 raceway on the right side. The conductors from one trade size 2 1/2 raceway (on the left wall) are pulled through the raceway on the right wall. The other trade size 2 1/2 raceway conductors (on the left wall) are pulled through a trade size 2 1/2 raceway at the bottom of the pull box. See Figure.
20 in.
What's the nameplate FLA for a 5 hp, 230V, single-phase motor with a 93 percent power factor and an 87 percent efficiency rating?
20A
If a branch circuit supplies a single nonmotor-operated appliance, the rating of overcurrent protection shall not exceed _____ if the overcurrent protection rating is not marked and the appliance is rated 13.30A or less.
20A 422.11(E)(2)
A primary transformer winding operates at 240V, the secondary at 12V, and the load is two 100W lamps. What's the primary VA load if the transformer is rated 92 percent efficient?
217 VA.
Determine the minimum number of cubic inches required for two 10 AWG conductors passing through a box, four 14 AWG conductors spliced in the box, two 12 AWG conductors terminating to a receptacle, and one 12 AWG equipment bonding jumper from the receptacle to the box.
22 cu in.
A 240V, 40A, single-phase load is located 150 ft from an existing junction box. The junction box is located 50 ft from the panelboard. When the 40A load is on, the voltage at the junction box is calculated to be 236V. The NEC recommends that the voltage drop for this branch circuit not exceed three percent of the 240V source (7.20V). What size copper conductors can be installed from the junction box to the load and still meet the NEC recommendations for branch circuits?
3 AWG
Where rock bottom is encountered when driving a ground rod at an angle up to 45º, the electrode can be buried in a trench that is at least _____ deep.
30 in. 250.53(G)
For installations consisting of not more than two 2 wire branch circuits, the service disconnecting means shall have a rating of not less than _____.
30A 230.79(B)
How far can a 230V, 50A, three-phase load be located from a panelboard if it's fed with 3 AWG conductors and still meet the NEC recommendations for voltage drop for branch circuits?
325 ft
Listed outlet boxes to support ceiling-suspended fans that weigh more than _____ lb shall have the maximum allowable weight marked on the box.
35 314.27(C)
What's the voltage drop of two 3 AWG aluminum conductors that supply a 5 hp, 115V, single-phase motor that has a nameplate rating of 55A? The motor is located 95 ft from the power supply.
4.21V
The primary current of the transformer is _____. See Figure.
4.38A
The motor feeder conductor size for three 15 hp, 208V, three-phase motors; three 3 hp, 208V, single-phase motors; and three 1 hp, 120V, single-phase motors will be _____. (75°C rated terminals)
4/0 AWG
Enclosures for switches or overcurrent devices are allowed to have conductors feeding through where the wiring space at any cross section is not filled to more than _____ percent of the cross-sectional area of the space.
40 312.8(A)(1)
What size motor, in horsepower, is required to produce approximately 30 kW of output?
40 hp
The approximate primary kVA of a transformer that supplies a 208V, 100A, three-phase load is _____. See Figure.
42 kVA
What's the conductor power loss for a 120V circuit that has a 3 percent voltage drop and carries a current flow of 12A? P = I x E; P = 12A x (120V x 3%)
43W
Interior metal water piping that is electrically continuous with a metal underground water pipe electrode and is located not more than _____ ft from the point of entrance to the building shall be permitted to extend the connection to an electrode(s).
5 250.68(C)(1)
Grounding electrodes of the rod type less than _____ in diameter shall be listed.
5/8 in. 250.52(A)(5)(b)
When a motor starts, the current drawn is at least _____ times the motor FLA; this is known as "motor locked-rotor amperes" (LRA).
6
All switchboards, switchgear, panelboards, and motor control centers shall be located in dedicated spaces and protected from damage and, for outdoor installations, the space equal to the width and depth of the equipment, and extending from grade to a height of _____ ft above the equipment, shall be dedicated to the electrical installation.
6 (110.26(E)(2)(c)
Type MC cable shall be secured at intervals not exceeding _____ ft.
6 330.30(B)
The input VA of a 5 hp (15.20A), 230V, three-phase motor is closest to _____.
6,100 VA
A transformer primary winding operates at 240V, the secondary at 120V, and the load is 1,500W. If the transformer is rated 92 percent efficient, what's the current flowing through the primary winding of this transformer?
6.80A
Where raceways or cables are exposed to direct sunlight on or above rooftops, raceways or cables shall be installed a minimum distance of _____ in. above the roof to the bottom of the raceway or cable.
7/8 310.15(B)(3)(c)
The branch-circuit short-circuit and ground-fault protection (circuit breaker) for a 125 hp, 240V, direct-current motor is _____.
700A
What's the apparent power in VA of a fluorescent ballast that has a power factor of 90 percent when connected to two 34W lamps?
76 VA
Underground copper service conductors shall not be smaller than _____ AWG copper.
8 230.31(B)
Where direct-buried conductors and cables emerge from grade, they shall be protected by enclosures or raceways to a point at least _____ ft above finished grade.
8 300.5(D)(1)
No parts of cord-connected luminaires, chain-, cable-, or cord-suspended luminaires, lighting track, pendants, or paddle fans shall be located within a zone measured 3 ft horizontally and _____ ft vertically from the top of the bathtub rim or shower stall threshold.
8 410.10(D)
The feeder calculated load for an 8 kW load, increased by 20 percent is _____.
9.60 kW
The efficiency ratio of a 4,000 VA transformer winding with a secondary VA of 3,600 VA is _____ percent.
90
What size outlet box is required for one 12/2 W/G NM cable that terminates on a switch, one 12/3 W/G NM cable that terminates on a receptacle, and the box has cable clamps?
A 4 in. x 2 1/8 in. square box.
The number of conductors permitted in a raceway is dependent on the _____.
ALL OF THESE
_____ enclosures are constructed so that dust will not enter under specific test conditions.
Dusttight (100)
_____ can be reduced by dividing the core into many flat sections or laminations.
Eddy currents
If exposed structural metal that is interconnected to form the building frame exists in the area served by the separately derived system, it shall be bonded to the grounded conductor of each separately derived system and each bonding jumper shall be sized in accordance with Table 250.102(C)(1) based on the largest ungrounded conductor of the service.
False 250.104(D)(2)
The structural metal frame of a building can be used as the required equipment grounding conductor for ac equipment.
False 250.136(A)
For grounded systems, the earth is considered an effective ground fault current path.
False 250.4(A)(5)
Currents that introduce noise or data errors in electronic equipment are considered objectionable currents in the context of 250.6(d) of the NEC.
False 250.6(D)
Article 285 covers surge protective devices rated over 1 kV.
False 285.1
Surge protective devices shall only be located outdoors.
False 285.11
Type _____ cable is a factory assembly of insulated circuit conductors within an armor of interlocking metal tape, or a smooth or corrugated metallic sheath.
MC 330.2 Metal Clad Cable, Type MC
_____ shall be permitted to support the wiring methods and equipment permitted to be used in other spaces used for environmental air (plenum).
Metal cable tray systems 300.22(C)(2)(a)
For general motor applications, the motor branch-circuit short-circuit and ground-fault protection device shall be sized based on the _____ values.
NEC Table 430.6(A)(1)
Type _____ cable is a factory assembly that encloses two or more insulated conductors within a nonmetallic jacket.
NM 334.2 Nonmetallic-Sheathed Cable
What's the minimum size THHN conductor permitted to terminate on a 70A circuit breaker or fuse if the circuit breaker and equipment terminals are listed for 75°C conductor sizing?
NOT - 4AWG
What's the ampacity of nine 10 THW current-carrying conductors with on equipment grounding conductor in a PVC raceway located in an ambient temperature of 46°C?
NOT - 17.40A
What's the ampacity of 10 THHN conductors if there are thirty-one conductors in a cross-sectional area of a wireway?
NOT - 18A
_____ conductors shall not be used for more than one branch circuit, one multiwire branch circuit, or more than one set of ungrounded feeder conductors except as allowed elsewhere in the Code.
Neutral 200.4(A)
Type _____ cable is an assembly primarily used for services.
SE 338.2 Service-Entrance Cable
What trade size ENT raceway is required for four Cat 6 cables having a diameter of 0.22 inches?
Trade Size 3/4
What's the minimum trade size EMT for Type NM cable having a major diameter (ellipse) of 0.50 in.?
Trade size 3/4
A half-wave rectifier can be used to convert alternating-current voltage into direct-current voltage allowing it to continuously charge a capacitor during both alternations of the alternating- current sine wave.
True
A multiwire branch circuit has two or more ungrounded conductors having a potential difference between them, and having an equal difference of potential between each ungrounded conductor and the grounded conductor.
True
According to Kirchoff's Current Law, the total current provided by the source to a parallel circuit equals the sum of the currents of all of the branches.
True
Because of conductor resistance, flux leakage, eddy currents, and hysteresis losses, not all of the input power is transferred to the secondary winding for useful purposes.
True
Capacitors are used to start single-phase alternating-current motors and to prevent arcing across the contacts of electric switches.
True
Effective alternating current voltage or effective alternating current is the equivalent value of direct current voltage or direct current that will produce the same amount of heat in a resistor.
True
Effective alternating-current voltage or effective alternating current is the equivalent value of direct-current voltage or direct current that will produce the same amount of heat in a resistor.
True
Even when power is removed from the circuit, capacitors can store large amounts of energy for a long period of time, and can discharge and arc if inadvertently shorted or grounded out.
True
If the ampacity of a conductor doesn't correspond with the standard ampere rating of a fuse or circuit breaker, the next size up overcurrent protec-tion device is permitted. This applies only if the conductors supply multioutlet receptacles for portable cord-and-plug-connected loads.
True
No matter how many resistances there are in a series circuit, the sum of the voltages across all of the resistances equals the voltage of the source according to the Resistance Law of Proportion.
True
EMT shall not be threaded.
True 358.28(B)
Each motor shall be provided with an individual controller.
Trur 430.87
Edison base fuseholders shall be used only if they are made to accept _____ fuses by the use of adapters.
Type S 240.52
Type _____ cable is a factory assembly of conductors with an overall covering of nonmetallic material suitable for direct burial in the earth.
UF 340.2 Underground Feeder and Branch-Circuit Cable, Type UF
Type _____ cable is a multiconductor assembly identified for use as underground service-entrance cable.
USE Type _____ cable is a multiconductor assembly identified for use as underground service-entrance cable.
_____ alternating current systems operating at 480V shall have ground detectors installed on the system.
Ungrounded 250.21(B)(1)
The ampacities listed in 310.15 do not take _____ into consideration.
voltage drop 310.15(A)(1) Note 1
Entrances to rooms and other guarded locations containing exposed live parts shall be marked with conspicuous _____ forbidding unqualified persons to enter.
warning signs (110.27(C))
If a transformer primary winding has 900 turns and the secondary winding has 90 turns, which winding of the transformer has a larger conductor in cross-sectional area?
The secondary winding.
If the primary transformer winding operates at 480V and the secondary at 240V, which winding has a larger conductor in cross-sectional area?
The secondary winding.
A balanced 3-wire, 120/240V, single-phase circuit is connected so that the ungrounded conductors are from different transformer lines (Line 1 and Line 2). The current in the neutral conductor is _____ of the ungrounded conductor current.
0 percent
The power consumed by a resistor can be expressed by the formula I2 x R . If 120V is applied to a 10-ohm resistor, the power consumed will be _____. P = E2/R
1,440W
Resistor R1 has a resistance of 5 ohms and resistors R2, R3, and R4 have a resistance of 15 ohms each. The total resistance of this series-parallel circuit is _____. See Figure.
10 ohms
The current in the neutral conductor of a 2-wire circuit is _____ of the current in the ungrounded conductor.
100 percent
A series circuit contains two resistors, one rated 4 ohms and the other rated 8 ohms. If the total voltage drop across both resistors equals 12V, then the current that passes through either resistor will be _____.
1A
What's the power loss of two 10 AWG conductors when the current through the circuit is 16A and the total resistance is 0.18 ohms? P = I2 x R
46W
Within sight from means visible and not more than _____ ft distant from the equipment.
50 (100 In Sight from (Within Sight From, Within Sight))
Where equipment operating at 1,000 volts, nominal, or less to ground and likely to require examination, adjustment, servicing, or maintenance while energized is required by installation instructions or function to be located in a space with limited access, all enclosure doors or hinged panels shall be capable of opening a minimum of _____ degrees.
90 (110.26(A)(4)(c))
Deriving the square root of a number is almost the same as squaring a number.
True
Direct current is used for electroplating, street trolley and railway systems, or where a smooth and wide range of speed control is required for a motor-driven application.
True
If the current in each ungrounded conductor of a multiwire branch circuit is the same, the neutral conductor carries 0A.
True
If you know the current of the circuit and the resistance of each resistor, the power of each resistor can be determined by the formula P = I2 x R.
True
For indoor installations, piping, ducts, leak protection apparatus, or other equipment foreign to the electrical installation shall not be installed in the dedicated space above a panelboard or switchboard.
True (110.26(E)(1)(a))
A cable routing assembly is composed of single or connected multiple channels as well as associated fittings, forming a structural system to _____ communications wires and cables, optical fiber and data cables; and Class 2, Class 3, and Type PLTC cables; and power-limited fire alarm cables in plenum, riser, and general-purpose applications.
a and b (100)
Where caution, warning, or danger signs or labels are required by this Code, the label marking shall warn of the hazards using effective _____.
any combination of words, colors, or symbols (110.21(B))
A conductor used to connect the system grounded conductor or the equipment to a grounding electrode or to a point on the grounding electrode system is called the "_____ conductor."
grounding electrode (100 Grounding Electrode Conductor)
When normally enclosed live parts are exposed for inspection or servicing, the working space, if in a passageway or general open space, shall be suitably _____.
guarded (110.26(B))
The common point on a 4-wire, three-phase, 120/208V wye-connected system is defined by the Code as the "_____ point."
neutral
A(n) _____ is a point on the wiring system at which current is taken to supply utilization equipment.
outlet (100)
If the supply voltage is 120V, the total energy consumed for four 10-ohm resistors will be more if all of the resistors are connected in _____.
parallel
When modifications to the electrical installation occur that affect the maximum available fault current at the service, the maximum available fault current shall be verified or _____ as necessary to ensure the service equipment ratings are sufficient for the maximum available fault current at the line terminals of the equipment.
recalculated (110.24(B))
To double the current of a circuit when the voltage remains constant, the R (resistance) must be _____.
reduced by half
The service drop is defined as the overhead conductors between the utility electric supply system and the _____.
service point (100 Service Drop)
The voltmeter connected across the switch reads _____. See Figure.
6V
Which of the following is the most conductive?
Salt water.
To calculate the energy consumed in watts by a resistive appliance, you need to know _____ of the circuit.
any of these pairs of variables
The voltmeters shown in the Figure are connected _____ each of the loads.
b and c
The term "rainproof" is typically used in conjunction with enclosure type(s) _____.
b and c (Table 110.28 Note 1)
A single-phase, dual-rated, 120/240V motor will have its winding connected in _____ when supplied by 120V.
parallel
What's the kW of a 75W load?
0.075 kW
A 1,500W resistive heater is rated 230V and is connected to a 208V supply. The power consumed by this load at 208V will be approximately _____ when the total resistance is 35.27 ohms. P = E2/R
1,225W
The reading of Voltmeter 2 (V2) is _____. See Figure.
1.50V
What's the maximum distance that two 14 AWG copper conductors can be run if they carry 16A and the maximum allowable voltage drop is 10V? D = (Cmil x E^VD)/(2 x K x I)
100 ft
All switchboards, switchgear, panelboards, and motor control centers shall be located in dedicated spaces and protected from damage and the working clearance space for outdoor installations shall include the zone described in _____.
110.26(A) (110.26(E)(2)(b))
The total resistance of a circuit is 10.20 ohms. The load has a resistance of 10 ohms and the wire has a resistance of 0.20 ohms. If the current of the circuit is 12A, then the power consumed by the circuit conductors (0.20 ohms) is approximately _____. P = I2 x R
29W
The decimal equivalent for "300 percent" is _____.
3
The minimum working space on a circuit for equipment operating at 750 volts-to-ground, with exposed live parts on one side and grounded parts on the other side of the working space, is _____ ft.
4 (110.26(A)(1) and Table 110.26(A)(1), Condition 2)
An overcurrent device (circuit breaker or fuse) must be sized no less than 125 percent of the continuous load. If the load is 16A, the overcurrent device will have to be sized at no less than _____.
20A
Determine the total circuit resistance of the parallel circuit shown in the Figure based on the following facts:1. The current on ammeter 1 reads 0.75A.2. The voltage of the circuit is 30V.3. Bell 2 has a resistance of 48 ohms.Tip: The total resistance of a parallel circuit is always less than the smallest resistor.
22 ohms
The polarity and the output voltage from a direct-current power source changes direction. One terminal will be negative and the other will be positive at one moment, then the terminals switch polarity.
False
Access and _____ shall be provided and maintained about all electrical equipment to permit ready and safe operation and maintenance of such equipment.
working space (110.26)
The neutral conductor of a 3-wire, 120/208V or 277/480V circuit supplied from a 4-wire, three-phase system never carries neutral current.
True
The neutral conductor of a 3-wire, 120/240V, single-phase circuit only carries current when the current in the ungrounded conductors isn't identical.
True
What's the power loss in watts of a conductor that carries 24A and has a voltage drop of 7.20V? P = I x E
175W
In the Figure, the total current of the circuit can be measured by ammeter _____.
A3
Multiwire branch circuits have more conductors for a given number of circuits, which requires the use of a larger raceway.
True
Resistance opposes the flow of electrons. In a series circuit, the total circuit resistance is equal to the sum of all of the resistances in series.
True
The grounded conductor is a conductor that's intentionally grounded to the earth.
True
The power consumed in a series circuit is equal to the power consumed by the largest resistance in the series circuit.
True
When working any formula, the key to calculating the correct answer is following these four steps: Step 1: Know what the question is asking you to find. Step 2: Determine the knowns of the circuit. Step 3: Select the formula. Step 4: Work out the formula calculation.
True
In many circumstances, the authority having jurisdiction can be a property owner or his/her designated agent.
True (100 Note, Authority Having Jurisdiction)
An accessory, such as a locknut, intended primarily to perform a mechanical function rather than an electrical function best describes _____.
a fitting (100)
An ohmmeter is being used to test a relay coil. The equipment instructions indicate that the resistance of the coil should be between 30 and 33 ohms. The ohmmeter indicates that the actual resistance is less than 22 ohms. This reading most likely indicates _____.
a shorted coil
Conductor terminal and splicing devices shall be _____ for the conductor material and they shall be properly installed and used.
identified (110.14)
The energy consumed by a 5-ohm resistor is _____ than the energy consumed by a 10-ohm resistor, assuming the current in both cases remains the same.
less
In general, when multiple light bulbs are wired in a single luminaire, they're connected in _____ to each other.
parallel
NFPA 70E, Standard for Electrical Safety in the Workplace, provides guidance, such as determining severity of potential exposure, planning safe work practices, arc-flash labeling, and selecting _____.
personal protective equipment (110.16(B) Note 1)
A single receptacle is a single contact device with no other contact device on the same _____.
yoke (100)
