Final Spring 2020

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Type NM cable can be supported and secured by _____.

staples cable ties straps

Motors shall be located so that adequate _____ is provided and so that maintenance, such as lubrication of bearings and replacing of brushes, can be readily accomplished.

ventilation

Armatures are wound to provide high voltage, high current, or some specific combination of voltage and current. Which type of winding provides high voltage and low current?

wave-wound

The common grounding electrode conductor installed for multiple separately derived systems shall not be smaller than ______ copper when using a wire-type conductor.

3/0 AWG

The insulation temperature rating of conductors in Type NM cable shall be _____.

90 degrees Celscius

A generator containing both series and shunt fields is called a _____ generator.

compound

Handhole enclosure covers shall have an identifying ______ that prominently identifies the function of the enclosure, such as "electric."

mark or logo

Pull boxes or junction boxes with any dimension over ______ ft shall have all conductors cabled or racked in an approved manner.

6

A wye-connected alternator that has phase voltages of 277 V is feeding two loads. The first load is wye-connected inductors that have 40 Ω of XL. The second load is delta-connected capacitors that have XC of 60 Ω. How much is the alternator phase current?

6.93 A

A delta connected set of windings has a phase voltage of 480 V. What is the line voltage?

480 V

The output voltage of a generator is usually controlled by the amount of

field excitation current

When installing direct-buried cables, a ______ shall be used at the end of a conduit that terminates underground.

terminal fitting bushing

The _____ motor can operate on either AC or DC voltage.

universal

Liquidtight flexible metal conduit must be securely fastened by a means approved by the authority having jurisdiction within ______ of termination.

1 ft

Type AC cable shall be secured at intervals not exceeding 4½ ft and within ______ in. of every outlet box, cabinet, conduit body, or fitting.

12

Snap switches rated _____ or less directly connected to aluminum conductors shall be listed and marked CO/ALR.

20A

When Type AC cable is run across the top of a floor joist in an attic without permanent ladders or stairs, guard strips within ______ of the scuttle hole or attic entrance shall protect the cable.

6 ft

Type AC cable installed in thermal insulation shall have conductors that are rated at 90°C. The ampacity of the cable in this application shall not exceed that of a ______ rated conductor

60 degrees Celscius

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.

7

Luminaires and equipment must be mechanically connected to an equipment grounding conductor as specified in 250.118 and must be sized in accordance with ______.

Table 250.122

EMT, elbows, couplings, and fittings can be installed in concrete, in direct contact with the earth, or in areas subject to severe corrosive influences if ______.

a and b

The allowable ampacity of flexible cords and cables is found in _____

Tables 400.5(A)(1) and (2)

ENT and fittings can be_____, provided fittings identified for this purpose are used.

encased in poured concrete or embedded in a concrete slab on grade where the tubing is placed on sand or approved screenings

Steel or aluminum cable tray systems shall be permitted to be used as an equipment grounding conductor, provided the cable tray sections and fittings are identified as ______, among other requirements.

an equipment grounding conductor

Lampholders shall be constructed, installed, or equipped with shades or guards so that _____ isn't subjected to temperatures in excess of 90°C (194°F).

combustible material

Each run of cable tray shall be ______ before the installation of cables.

completed

A compound generator has both series and shunt field windings. When those windings are connected so they aid each other in the production of magnetism, that connection is called

cumulative-compound

A switchboard or panelboard containing a 4-wire, _____ system where the midpoint of one phase winding is grounded, shall be legibly and permanently field-marked to caution that one phase has a higher voltage-to-ground.

delta-connected

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 protection against ______.

physical damage

Poles over 20 ft in height above grade, without a hinged base, that support luminaires shall _____.

have an accessible handhole (sized 2 x 4 in.) with a cover suitable for use in wet locations and have an equipment grounding terminal that is accessible from the handhole

Type NM cable on a wall of an unfinished basement installed in a listed raceway shall have a(n) _____ installed at the point where the cable enters the raceway.

insulating bushing or adapter

Type NM cable shall be _____.

listed

Cut ends of FMC shall be trimmed or otherwise finished to remove rough edges, except where fittings

thread into the convolutions

A receptacle installed in an outlet box flush-mounted in a finished surface in a damp or wet location shall be made weatherproof by means of a weatherproof faceplate assembly that provides a _____ connection between the plate and the finished surface.

watertight

Surface-mounted switches or circuit breakers in a damp or wet location shall be enclosed in a ______ enclosure or cabinet that complies with 312.2.

weatherproof

Lampholders installed in wet locations shall be listed for use in _____ locations.

wet

Type ______ cable is a factory assembly that encloses two or more insulated conductors within a nonmetallic jacket.

NM

Joints between PVC conduit, couplings, fittings, and boxes shall be made by ______.

an approved method

Where portions of a cable raceway or sleeve are subjected to different temperatures and condensation is known to be a problem, the ______ shall be filled with an approved material to prevent the circulation of warm air to a colder section of the raceway or sleeve.

raceway or sleeve

In a three-phase motor, the speed of rotation of the magnetic field is called the _____ speed.

synchronous

A branch-circuit overcurrent device can serve as the disconnecting means for a stationary motor of 1/8 hp or less.

true

Each tap conductor to a common grounding electrode conductor for multiple separately derived systems shall be sized in accordance with ______, based on the derived ungrounded conductors of the separately derived system it serves.

250.66

A vertically mounted luminaire weighing not more than ______ can be supported to a device box or plaster ring with no fewer than two No. 6 or larger screws.

6 lb

It shall be permissible to ground meter enclosures located near the service disconnecting means to the ______ circuit conductor on the load side of the service disconnect, if service ground-fault protection is not provided.

grounded

A(n) _____ conductor that carries only the unbalanced current from other conductors of the same circuit shall not be required to be counted when applying the provisions of 310.15(B)(3)(a).

neutral

Small permanent magnet motors that have lightweight rotors are often used as _____.

servomotors

Where more than one motor disconnecting means is provided in the same motor branch circuit, at least one of the disconnecting means shall be readily accessible.

true

The interior of underground raceways shall be considered a ______ location.

wet

The ampacity of a conductor can be different along the length of the conductor. The higher ampacity can be used beyond the point of transition for a distance of no more than ______ ft, or no more than ______ percent of the circuit length figured at the higher ampacity, whichever is less.

10, 10

Cut ends of ENT shall be trimmed inside and _____ to remove rough edges.

outside

The _____ winding is made of many turns of small wire and is located at the top of the stator core of a split-phase motor.

start

Each cable entering a cutout box _____

shall be secured to the cutout box

A motor can be provided with combined overcurrent protection using a single protective device to provide branch-circuit _____ protection where the rating of the device provides the overload protection specified in 430.32.

short circuit ground-fault motor overload

In the shaded-pole induction motor, the shading coil acts like a transformer with a(n) _____ secondary winding.

shorted

Three-phase voltages are _____ out of phase with each other.

120 degrees

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

In determining the highest rated motor for purposes of 430.24, the highest rated motor shall be based on the rated full-load current as selected _____.

from Tables 430.247, 430.248, 430.249, and 430.250

Parallel conductors shall have the same ______

length material size in circular mil area

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

Handhole enclosures shall be designed and installed to withstand ______

all loads likely to be imposed

The speed regulation of a DC motor is proportional to the _____.

armature resistance

Outlet boxes can be secured to suspended-ceiling framing members by mechanical means such as _____, or by other means identified for the suspended-ceiling framing member(s).

bolts screws and rivets

Extreme ______ may cause PVC conduit to become brittle, and therefore more susceptible to damage from physical contact.

cold

The universal motor has a wound armature and brushes like an AC motor, as well as an added component, the _____.

compensating winding

Each strap containing one or more devices shall count as a _____ volume allowance in accordance with Table 314.16(B), based on the largest conductor connected to a device(s) or equipment supported by the strap.

double

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.

embedded or ensaded in concrete or in direct contact with the earth

Electrical equipment with _____ and having adequate fire-resistant and low-smoke-producing characteristics can be installed within an air-handling space (plenum).

a metal enclosure or a nonmetallic enclosure listed for use within an air-handling (plenum) space

A motor disconnecting means can be a listed _____.

molded case circuit breaker motor-circuit switch rated in horsepower molded case switch

Nonmetallic cables can enter the top of surface-mounted cabinets, cutout boxes, and meter socket enclosures through nonflexible raceways not less than 18 in. or more than ______ ft in length if all of the required conditions are met.

10

When mounting an enclosure in a finished surface, the enclosure shall be _____ secured to the surface by clamps, anchors, or fittings identified for the application.

rigidly

The series generator has only a series field, which is connected in _____ with the armature.

series

A wood brace used for supporting a box for structural mounting shall have a cross-section not less than nominal _

1 in. x 2 in.

Conductor adjustment factors shall not apply to conductors in raceways having a length not exceeding ______ in.

24

PVC conduit shall be securely fastened within ______ in. of each box.

36

The total marked rating of a cord-and-plug-connected room air conditioner, connected to the same branch circuit which supplies lighting units, other appliances, or general-use receptacles, shall not exceed _____ percent of the branch-circuit rating.

50

THWN insulated conductors are rated ______.

75 degrees Celscius for wet locations

The frequency of the current in a squirrel-cage rotor _____ as the rotor approaches synchronous speed.

decreases

Line voltage and phase voltage are the same in the _____ connection.

delta

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 conditions.

made of material

Type UF cable shall not be used in ______.

motion picture studios storage battery rooms hoistways

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

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

Two intermediate metal or rigid metal conduits threaded wrenchtight into an enclosure can be used to support an outlet box containing devices or luminaires, if each raceway is supported within _____ in. of the box.

18

A cable, raceway, or box installed under metal-corrugated sheet roof decking shall be supported so the top of the cable, raceway, or box is not less than _____ from the lowest surface of the roof decking to the top of the cable, raceway, or box. ½ in.

1½ in.

When a ground ring is used as a grounding electrode, it shall be buried at a depth below the earth's surface of not less than ______.

30 in

Motor control circuit conductors that extend beyond the motor control equipment enclosure shall have short-circuit and ground-fault protection sized not greater than _____ percent of value specified in Table 310.15(B)(16) for 60°C conductors.

300

For Type 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 90ºC conductor insulation rating [310.15(B)(2)], provided the adjusted or corrected ampacity doesn't exceed that of a _____ rated conductor.

60 degrees Celscius

For general motor applications, the motor branch-circuit short-circuit and ground-fault protection device shall be sized based on the _____ values.

NEC Table

Where service-entrance phase conductors are installed in parallel in two or more raceways, the size of the grounded conductor in each raceway shall be based on the total circular mil area of the parallel ungrounded service-entrance conductors in the raceway, sized in accordance with 250.24(C)(1), but not smaller than ______.

1/10 AWG

An equipment grounding conductor shall be identified by ______.

all of the above

Electrical continuity at service equipment, service raceways, and service conductor enclosures shall be ensured by ______.

all of the above

For permanently connected motor-operated appliances with motors rated over _____, a switch or circuit breaker located within sight from the motor operated appliance can serve as the appliance disconnect.

1/8 hp

_____, 125V and 250V receptacles installed in a wet location shall have an enclosure that is weatherproof whether or not the attachment plug cap is inserted.

15A or 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

Thermal insulation shall not be installed above a recessed luminaire or within _____ in. of the recessed luminarie's enclosure, wiring compartment, ballast, transformer, LED driver, or power supply unless it is identified as a Type IC luminaire.

3

Lighting track shall not be installed less than _____ ft above the finished floor except where protected from physical damage or where the track operates at less than 30V rms, open-circuit voltage.

5

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

Lighting track shall not be installed within the zone measured 3 ft horizontally and _____ ft vertically from the top of the bathtub rim or shower stall threshold.

8

Which of the following types of luminaires can be installed in a clothes closet?

A surface or recessed incandescent luminaire with completely enclosed light source. A surface or recessed fluorescent luminaire. A surface-mounted or recessed LED luminaire with a completely enclosed light source.

______ is a listed thin-wall, metallic tubing of circular cross section used for the installation and physical protection of electrical conductors when joined together with listed fittings.

EMT

Luminaires containing a metal halide lamp (other than a thick-glass PAR lamp) shall be provided with a containment barrier that encloses the lamp, or shall be provided with a physical means that only allows the use of a(n) _____.

Type O lamp

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 _____.

accessible to qualified persons a single device located in sight of the disconnecting means

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(3)(a)

Alternating-current general-use snap switches are permitted to control _____.

all of the above

FMC shall not be installed ______.

all of the above

IMC must be secured _____

all of the above

LFNC shall be permitted for _____.

all of the above

Luminaires must maintain a minimum clearance from the closet storage space of _____.

all of the above

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 the above

Which of the following switches must indicate whether they are in the open (off) or closed (on) position?

all of the above

_______ wiring methods can be installed in a cable tray.

all of the above

Type NM and Type NMC cables shall be permitted in _____.

all the above

Power distribution blocks installed in metal wireways shall ______.

allow for sufficient wire-bending space at terminals AND not have uninsulated exposed live parts

Bends in LFNC shall _____ between pull points.

be limited to 360 degrees

A receptacle is considered to be in a location protected from the weather when located under roofed open porches, canopies, marquees, and the like, where it will not be subjected to _____.

beating rain or water runoff

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.

branch circuits or feeders

Nonlocking type 15A and 20A, 125V receptacles in _____ must be listed as tamper resistant.

child care facilities

Cord-and-plug-connected vending machines manufactured or remanufactured on or after January 1, 2005 shall include a ground-fault circuit interrupter identified for portable use as an integral part of the attachment plug or in the power-supply cord within 12 in. of the attachment plug. Older vending machines not incorporating integral GFCI protection shall be ______.

connected to a GFCI-protected outlet

Lampholders installed in damp locations shall be listed for use in _____ locations.

damp or wet

An outdoor receptacle in a location protected from the weather, or in another damp location, shall be installed in an enclosure that is weatherproof when the receptacle is _____.

enclosed

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

Snap switches installed in boxes shall have the _____ seated against the finished wall surface

extension plaster ears

Type MC cable can be unsupported where the cable is _____.

fished between concealed access points in finished buildings or structures and support is impracticable or not more than 6 ft from the last point of support within an accessible ceiling for the connection of luminaires or other electrical equipment

Flexible cords shall not be used as a substitute for _____ wiring.

fixed

Luminaires using a _____ lamp, that is subject to physical damage and installed in playing and spectator seating areas of indoor sports, mixed-use, or all-purpose facilities, shall be of the type that protects the lamp with a glass or plastic lens.

fluorescent

Where practicable, contact of dissimilar metals shall be avoided in an IMC raceway installation to prevent

galvanic action

When 15A and 20A receptacles are installed in a wet location, the outlet box ______ must be listed for extra-duty use.

hood

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

Flexible cords and cables shall be connected to fittings so that tension will not be transmitted to joints or terminal screws by _____.

knotting the cord winding the cord with tape fittings designed for the purpose

Where the air conditioner disconnecting means is not within sight from the equipment, the disconnecting means must be ______.

lockable

In the shaded-pole induction motor, the direction of rotation of the magnetic field is determined by the _____.

magnetic field strength

Coves for luminaires shall be located so that the lamps and equipment can be properly installed and _____.

maintained

Underground raceways and cable assemblies entering a handhole enclosure shall extend into the enclosure, but they are not required to be ______.

mechanically connected to the handhole enclosure

Luminaires located within the actual outside dimension of a bathtub and shower shall be marked for damp locations, or marked for wet locations where they are _____.

not GFCI protected

Where insulated conductors are deflected within a metal wireway, the wireway shall be sized to meet the bending requirements corresponding to ______ wire per terminal in Table 312.6(A).

one

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 ______.

provided with a faceplate of nonconduction, noncombustible material with nonmetallic screws or GFCI protected

Luminaires installed in _____ shall comply with 410.115 through 410.122.

recessed cavities in walls or ceilings and suspended ceilings

Luminaires shall be wired so that the _____ of each lampholder is connected to the same luminaire or circuit conductor or terminal.

screw shell

Flexible metal conduit shall not be required to be ______ where fished between access points through concealed spaces in finished buildings or structures and supporting is impracticable.

secured or supported

A luminaire marked "Suitable for Wet Locations" _____ be permitted to be used in a damp location.

shall

Each appliance shall have a means that _____ disconnects all ungrounded circuit conductors.

simultaneously

Recessed incandescent luminaires shall have _____ protection and shall be identified as thermally protected.

thermal

Enclosures not over 100 cu in. having threaded entries and not containing a device shall be considered to be adequately supported where ______ or more conduits are threaded wrenchtight into the enclosure and each conduit is secured within 3 ft of the enclosure.

two

For most squirrel-cage induction motors the typical percent slip is about _____ percent.

two to five

Track lighting shall not be installed _____.

where likely to be subjected to physical damage or in wet or damp locations

Cables laid in wood notches require protection against nails or screws by using a steel plate at least _____ thick, installed before the building finish is applied.

1/16 in

Where nails or screws are likely to penetrate nonmetallic-sheathed cable or ENT installed through metal framing members, a steel sleeve, steel plate, or steel clip not less than _____ in thickness shall be used to protect the cable or tubing.

1/16 in

Where Type NM cables pass through cut or drilled slots or holes in metal members, the cable shall be protected by _____ which are installed in the opening prior to the installation of the cable and which securely cover all metal edges.

listed bushings or listed grommets

The space above a hung ceiling used for environmental air-handling purposes is an example of ______, and the wiring limitations of ______ apply.

other space used for environmental air (plenum), 300.22(C)

Some motors are constructed so that they will operate on either of two voltages. When they are connected to operate on the lower of the two voltages, the windings are connected in _____.

parallel

Where one or more equipment grounding conductors enter a box, a _____ volume allowance in accordance with Table 314.16(B) shall be made based on the largest equipment grounding conductor.

single

Type ______ cable is a factory assembly of conductors with an overall covering of nonmetallic material suitable for direct burial in the earth.

UF

Listed FMC can be used as the equipment grounding conductor if the length in any ground return path does not exceed 6 ft and the circuit conductors contained in the conduit are protected by overcurrent devices rated at ______ or less.

20A

The maximum rating or setting of an inverse time breaker used as the motor branch-circuit short-circuit and ground-fault protective device for a single-phase motor is _____ percent of the full-load current given in Table 430.248.

250

Electrical equipment permanently mounted on skids, and the skids themselves, shall be connected to the equipment grounding conductor sized as required by ______.

250.122

A building or structure shall have the interior metal water piping system bonded with a conductor sized in accordance with ______

Table 250.66

It shall be permissible to ground meter enclosures located near the service disconnecting means to the ______ circuit conductor on the load side of the service disconnect, if service ground-fault protection is not provided.

all of the above

Openings around electrical penetrations into or through fire-resistant-rated walls, partitions, floors, or ceilings shall ______ to maintain the fire-resistance rating.

be firestopped using approved methods

The motor that does not contain a wound armature, commutator, or brushes is the _____ motor.

brushless DC

Each direct-buried single conductor cable must be located ______ in the trench to the other single conductor cables in the same parallel set of conductors, including equipment grounding conductors.

in close proximity

______ on equipment to be grounded shall be removed from contact surfaces to ensure good electrical continuity.

paint lacquer enamel

Conduits or raceways through which moisture may contact live parts shall be ______ at either or both ends.

sealed or plugged

An unspliced ______ that is sized based on the derived phase conductors shall be used to connect the grounded conductor and the supply-side bonding jumper, or the equipment grounding conductor, or both, at a separately derived system.

system bonding jumper

Three lines supply power to a three-phase motor. If one of these lines should open, the motor will be connected to single-phase power. This condition is known as _____.

single-phasing

Openings in cabinets, cutout boxes, and meter socket enclosures through which conductors enter shall be ______.

closed in an approved manner

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.

on and within

In three-phase power systems, the delivered power _____.

never falls to zero

The size of the grounding electrode conductor for a building or structure supplied by a feeder shall not be smaller than that identified in ______, based on the largest ungrounded supply conductor.

250.66

Overcurrent protection for motor control circuits shall not exceed _____ percent if the conductor is based on Table 310.15(B)(17) and does not extend beyond the motor control equipment enclosure.

400

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 supporting is impractical.

concealed

Metal boxes shall be ______ in accordance with Article 250.

grounded or bonded


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