Electrical Midterm 1

अब Quizwiz के साथ अपने होमवर्क और परीक्षाओं को एस करें!

Cables run parallel to (along) or through holes bored in framing members must be at least ____ inch(es) from the edge of the framing member.

1 - 1/4"

Where noncombustible surface material is used on walls or ceilings, outlet boxes must be mounted so that they will be set back not more than ____ from the face of the surface material.

1/4 in. (6 mm)

A 20-ampere branch circuit requires ____ AWG conductors, ignoring the effects of voltage drop.

12 copper

The open circuit voltage between the two terminals of a single-pole switch on a lighting circuit when the switch is in the off position is:

120 volts

Wiring devices for use on nominal 120-volt circuits are marked ____.

125 volts

The smallest wire size for which overcurrent protection is specified in the Code is ____.

14 AWG

Convenience receptacles connected to 20-ampere branch circuits are permitted to be rated ____.

15-ampere, 125-volt, 20-ampere, 125-volt

Alternating current, general-use snap switches are UL-listed to control motors rated up to ____ horsepower.

2

Type AC cable is manufactured with ____ phase conductors.

2, 3, 4

The minimum lighting load requirement for dwelling units is ____ volt-amperes per square ft (0.093 m3).

3

An arc flash can produce temperatures of ____°F.

35,000

Class A GFCI devices trip (open) when a ground-fault in the range of ____ milliamperes occurs.

4 to 6 milliamp

The total rating of utilization equipment fastened in place, other than luminaires (lighting fixtures), shall not exceed ____ percent of the branch-circuit ampere rating, where lighting units, cord and plug connected utilization equipment not fastened in place, or both, are also supplied.

50

Connectors marked ____ are suitable for use with aluminum, copper, or copper-clad conductors. Connectors not so marked are for use with copper conductors only.

AL/CU

For a given conductor size, which of the following material has the greatest ampacity?

Copper

Table 310.16 gives allowable ampacities of copper conductors with various types of insulation. When conductors will be used in ambient temperatures exceeding 30°C (86°F), the ____ for the table must be applied.

Correction factors

The National Electrical Code requires receptacles installed in a garage to be _________.

GFCI Protected

When an existing two-wire, nongrounding-type receptacle is replaced in a location where the Code requires a GFCI receptacle, it is permitted to be replaced by a ____.

GFCI receptacle

How is track lighting load in residences calculated?

It is considered to be part of the general lighting load of 3 volt-amperes per square foot.

According to ____, unused knockouts and other openings in electrical boxes and cabinets are required to be closed.

NEC 110.12 (A) and 314.17

Low voltage (high voltage drop) in a home can be caused by ____.

a conductor that is too small for the load, a circuit that is too long, poor connections at the terminals

The diagram below indicates ____.

a light controlled by three-way switches

GFCI protection is required for which of the following?

a receptacle installed within 6 feet of a wet-bar sink

The meaning of approved is

acceptable to the authority having jurisdiction

To avoid inductive heating in metallic raceways, the NEC requires that ____.

all circuit conductors be run in the same raceway

Under certain circumstances, the grounded (neutral) conductors of a residential service ____ permitted to be sized smaller than the phase conductors.

are

Phase conductors 6 AWG and smaller ____ permitted to be re-identified as equipment ground conductors using green paint, tape, or other effective means.

are not

Small appliance receptacle outlets ____ included in the 3 volt-ampere per square foot load calculation.

are not

The "12 foot rule" for spacing receptacles applies to all the following areas of a house, except for ____.

attics

When using conduit wiring methods, which of the following colors of insulation or marking are permitted to identify "hot" phase conductors?

black, red, and blue for 120/208-volt systems, yellow, orange, and brown for 277/480-volt systems, any colors except white, gray, or green

Ceiling fans are required to be installed on ____.

boxes marked "acceptable for fan support"

GFCI protection is not required for:

built in dishwasher

On isolated ground receptacles, the metal yoke ____ integrally bonded to the equipment grounding terminal of the receptacle.

is not

All of the following items of electrical equipment are devices, except for ____.

lamp

Devices are equipment whose primary function is to carry current not ____.

utilize electric energy

The grounded (identified) conductor of 6 AWG or smaller must have an outer finish that is:

white, gray, three continuous white stripes

Is a receptacle required on a 3 ft (914 mm) wall space behind a door that is normally left open?

yes

Branch-circuit conductors at outlet boxes are required to have at least ____ inches of free length for making splices and connections.

6

Wall receptacles in a habitable room must be placed so they are no further than ____ feet from any point along the wall.

6

The ampacity of Type NM cable shall be in accordance with ____ conductor temperature rating.

60 degree C or 140 degree F

A continuous load shall not exceed ____ of the rating of the branch circuit

80%

A dual-rated conductor marked THHN/THWN is rated ____ when used in dry locations.

90C (194F)

The suffix "B" in Type NMB nonmetallic cable means that the conductors have an insulation temperature rated ____.

90C (194F)

Article 210 applies to branch circuits, but branch-circuit calculations are covered in ____.

Article 220

Support and physical protection requirements for Type AC cable are similar to those for ____.

NM cable

Branch circuit conductors shall have an ampacity ____ than the maximum to be served.

Not less

The National Electrical Code gives measurements is which system of units first?

SI (metric)

Electrical wall boxes should not be mounted back-to-back in walls because ____.

Sound may be transmitted from room to room, it reduces fire resistance of the wall, the practice violates building codes

Liquidtight flexible nonmetallic conduit is subject to which of the following limitations?

cannot be used in direct sunlight, become brittle in extremely cold temp, cannot be direct buried

The 20-ampere appliance circuits required by NEC® are permitted to serve no other loads, except for ____.

clock outlets & receptacles intended for the cords of gas-fired cooking equipment

Type NM cable can be run in all the following locations, except for ____.

concealed in damp and moist locations, exterior masonry block or tile walls

Device faceplates must be mounted so as to ____.

cover the opening in the wall and sit against the wall surface

All of the following are included when calculating the usable area of a dwelling to compute the required lighting load, except for ____.

crawl space

In construction of one- and two-family dwellings, the electrical circuits are usually designed by the ____.

electrician

In order that the connections inside an outlet box remain accessible, the NEC® requires that a surface extension from an outlet box cover be made using ____.

flexible conduit

Where fixed glass panels (i.e., windows or non-sliding parts of door) do not permit installation of wall-mounted receptacles, ____ are typically used to satisfy the receptacle spacing requirements of the NEC.

floor-mounted receptacles

When using individual conductors in raceway, all of the following colors of insulation are permitted for the grounded conductor (neutral), except for ____.

green with three white stripes

The long slot on a 15-ampere, 125-volt receptacle is the ____ conductor.

grounded "neutral"

Armored cable includes a(n) ____ to insure a low-impedance grounding path.

internal bonding strip

A single or duplex receptacle installed in a basement or garage for a cord-and-plug connected receptacle in a dedicated space for an appliance such as a freezer or refrigerator ____ required to be protected by a ground-fault circuit-interrupter.

is

When a 4' piece of nonmetallic-sheathed cable is used as a fixture whip above an accessible ceiling, it ____.

is not required to be secured

Conductor sizes up through 4/0 AWG are expressed in American Wire Gauge (AWG). Conductor sizes larger than 4/0 AWG are expressed in ____.

kcmil

Older electrical books and plans sometimes use the term "MCM," which means the same thing as ____.

kcmil

NEC 406.3(D)(3) permits existing two-wire, nongrounded-type receptacles to be replaced with a ____ where no equipment grounding conductor exists.

two-wire nongrounding-type receptacle

The NEC requires that switching be done only in ____ conductors.

ungrounded

Grounding-type receptacles are permitted to be installed with the grounding terminal ____.

up, down, sideways

AFCI protection is required for all outlets in ________.

living room

NEC Article 210 provides ____ guidelines for locating receptacle outlets in residences.

mandatory

Snap switches with nonmetallic yokes (straps) have a terminal for the equipment grounding conductor. Using this type of switch provides a means for grounding ____ faceplates when nonmetallic boxes are used.

metal

In the international system of units, the prefix milli- means

one thousandth

The maximum number of Type NM cables that can be inserted into a connector is ____.

one, unless listed for more

The NEC requires that a(n) ____ be installed at each conductor splice or connection point.

outlet or junction box

The rating of a branch circuit is determined by its ____.

overcurrent PD (fuse and breakers)

As defined in Article 100, a dwelling unit has the following feature

permanent provisions for living, sleeping, cooking, and sanitation

When wiring houses with Type NM cable, it is generally more ____ to use two-wire cables than to use four-wire cable.

practical, economical

Listing or labeling of electrical equipment is done by a:

recognized testing laboratory

When receptacles or switches have 6-32 screws secured to them with small pieces of cardboard, these pieces of cardboard must be ____ when the wiring device is installed in a metal outlet box.

removed

The National Electrical Code is a minimum ____ standard.

safety

The NEC requires that conductors 8 AWG and larger must be ____ when installed in a raceway.

stranded

The National Electrical Code, allows Rigid PVC conduit to do all of the following, except for ____.

support lighting fixtures

The number of conductors permitted in rigid PVC schedule 80 conduit is specified in ____.

table C9, annex C

All 125V 15 and 20 amp receptacles in a dwelling are required to be ____.

tamper resistant

Nationally Recognized Testing Laboratories (NRTL) ____ electrical products to provide a basis for approval by inspectors in the field.

test and list

In the international system of units, the prefix kilo- means

thousand

The purpose of electrical symbols on plans is ____.

to graphically represent electrical products and systems


संबंधित स्टडी सेट्स

Chapter 31 : The Child with a Metabolic Condition

View Set