final 3a

Pataasin ang iyong marka sa homework at exams ngayon gamit ang Quizwiz!

conductor has a diameter of 40 mill what is the distance in inches

.04

what is the total resistance of a 2 wire circuit that spans the distance of 200'. each leg has a resistance per 1000' 1.21 omn

0.242

In a Class III location, pendant luminaires suspended by stems longer than _____ ft shall be provided with a fitting or flexible connector identified for the location, or shall be provided with effective bracing.

1

Telecom cables in an ER or TR subsystem must be separated from electrical conduit or cable by at least ____.

12" (300 mm)

The constant (K) for the resistance of ordinary copper is _____.

12.9 Ohms per mil foot

Use NEC Table 310.15(B)(16) to find the maximum ampacity for a No.2 AWG copper wire at (assume THHN insulation).

130a

The minimum size copper conductor permitted for branch circuits under 600V is _____ AWG

14

03. Straight conduit runs used in campus backbone systems should have pull boxes installed no more than __

140' (43 m) apart

The minimum size grounding conductor for fiber-optic cable is _____.

14AWG

When installing switches or other arc-producing apparatus in Class I, Division 1 locations, sealing fittings shall be installed within ____.

18" of the switch or other apparatus

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

How many division(s) are there for each hazardous atmosphere classification

2

How many classification(s) of hazardous atmospheres are listed in the NEC

3

When installing horizontal ER/TR/MC sleeves, the minimum distance between the ER/TR/MCs and the horizontal subsystem is ____

3" (75 mm)

Vertical cabling spans exceeding 30' (9 m) in riser support subsystems must be supported in __

30' (9 m) increments

correction factors due to high ambient temp are found in _________

310.15 b 2 a

How many group(s) are listed under Class 1, Division 1?

4

Of the following, the largest standard AWG wire size is ____.

4/0

the most common conductor used for light and power installations ________

4/0 - 14 awg

Riser pathways should run perpendicular to fluorescent lighting and be separated by a distance of least __

5" (125 mm)

Label conduit for a campus backbone within ____

6" (150 mm) of the termination point

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

cables meeting the requirements in 310.15 b if more than 20 current carrying conductors are installed longer than 24 inches without maintaining are stacked or are supported on.

60 percent

Which of the following is a standard fuse rating?

601A

the square mill of a conductor that is .250 in on all sides is _______ mills square

62500 mills squared

Which of the following is a standard configuration for stranded wire

7-strand

where conductors are installed in direct sunlight or above rooftops a temp added of . . . degrees when conduit is less than _____ to the rooftop

7/8

when installed in raceways. conductors ________ and larger shall be stranded unless permitted or required.

8 awg

to keep the voltage drop of a 277 circuit to a max 3 percent. what would be the max voltage drop.

8.31

if 5 #10 awg current carrying conductors are installed in a raceway where the ambiant temp is 70 degrees F. the ampacity must be _______ 310.15 ba 2a

80 percent

where 6 current carrying conductors are run in the same conduit. ampacity of each conductor shall be lowered to what percent of compacity?

80 percent

how much of a currection factor is tempurature is 40 degree c

82.

RJ45 connectors used for 4-pair UTP are identified as __

8P8C connectors

Which of the following best describes the time to pour in the sealing compound in a sealing fitting

After the conduit system and seals are installed and the conductors and packing fiber have been installed

Remote-control circuits for safety-control equipment shall be classified as _____ if the failure of the equipment to operate introduces a direct fire or life hazard.

Class 1

In Class II, Division 1 locations, control transformers, solenoids, impedance coils, resistors, and any overcurrent devices or switching mechanisms associated with them, shall have enclosures identified for _____.

Class II, Division 1 locations

Seals in Class II hazardous (classified) locations shall be explosionproof.

False

The Code covers underground mine installations and self propelled mobile surface mining machinery and its attendant electrical trailing cable.

False

You would find information on conductor applications and descriptions of insulation types in ____.

NEC Table 310.104(A)

The video cable used in new installations is normally ____

RG6

Class 1, 2, and 3 circuits installed through fire-resistant-rated walls, partitions, floors, or ceilings shall be firestopped to limit the possible spread of fire or products of combustion

True

Class 2 and Class 3 cable not terminated at equipment and not identified for future use with a tag is considered abandoned.

True

Due to its power limitations, a Class 2 circuit considers safety from a fire initiation standpoint and provides acceptable protection from electric shock

True

Hazards often occur because of __

a and b

Raceways permitted as a wiring method in Class II, Division 2 locations include _____.

a and b

Electric utilities may include entities that install, operate, and maintain _____.

a or b

Article 725 covers _____ circuits that are not an integral part of a device or of utilization equipment.

all of these

Class 2, Class 3, and Type PLTC cables shall be permitted to be installed in plenum cable routing assemblies, riser cable routing assemblies, and general purpose cable routing assemblies when ____

all of these

In Class III locations, _____ used as, or in conjunction with, control equipment for motors, generators, and appliances shall be provided with dusttight enclosures complying with the temperature limitations in 503.5.

all of these

In Class III locations, flexible cords shall _____.

all of these

Luminaires for fixed lighting in Class III locations shall have enclosures for lamps and lampholders that are designed to prevent the escape of _____.

all of these

Parallel conductors shall have the same _____.

all of these

The Code contains provisions considered necessary for safety, which will not necessarily result in _____

all of these

The NEC applies to the installation of _____

all of these

This Code covers the installation of _____ for public and private premises, including buildings, structures, mobile homes, recreational vehicles, and floating buildings.

all of these

Compliance with the provisions of the NEC will result in ___

an electrical system essentially free from hazard

In Class II locations, dust shall be prevented from entering the required dust-ignitionproof enclosure through a raceway by which of the following method(s)?

any of these

In Class III locations, motors, generators, and other rotating machinery shall be totally enclosed _____.

any of these

Raceways permitted in a Class III, Division 1 location include _____.

any of these

Where flexibility is required, the following wiring methods are permitted in a Class II, Division 2 location _____.

any of these

Flexible cords used in Class II, Division 1 or 2 locations shall _____, except as permitted for pendant luminaires.

be listed for extra-hard usage

A structured cabling subsystem that connects buildings together in a multi-building environment is called a(n) ____

campus backbone subsystem

the physical properties of a number 4/0 copper can be found in ______

chapter 9 table 8

The NEC does not apply to electric utility-owned wiring and equipment ______

consisting of service drops or service laterals

All things considered, the most ideal conductor is made of ____

copper

on a 4 wire wye circuit where the major portion of the load consists of non linear. the neutral wire shall be counted with __________

current carrying conductor

When installing circuit breakers in Class II, Division 1 hazardous locations, a ___.

dust/ ignition-proof enclosure must be used

Boxes and fittings shall be _____ where installed in a Class III location.

dusttight

Luminaires for fixed lighting in Class II, Division 2 locations shall be equipped with enclosures that are _____ or otherwise identified for the location.

dusttight

Signaling, alarm, remote-control, and communications system circuits containing contacts installed in Class II, Division 2 locations shall be in enclosures that are _____ or otherwise identified for the location.

dusttight

In Class II, Division 2 locations, enclosures for fuses, switches, circuit breakers, and motor controllers, including pushbuttons, relays, and similar devices shall be _____.

dusttight or otherwise identified for the location

Which of the following are the groups listed under Class II, Division 1

e,f,g,

In Class II, Division 1 locations, receptacles shall be part of the premises wiring and attachment plugs shall be of the type that provides for connection to the _____ of the flexible cord.

equipment grounding conductor

The main purpose of a union in conduit runs is to ____.

facilitate the installation and removal of equipment

Article 503 covers the requirements for electrical and electronic equipment and wiring in Class III locations where fire or explosion hazards may exist due to ignitible _____.

fibers/flyings

In Class III locations, receptacles and attachment plugs shall be of the grounding type, shall be designed so as to minimize the accumulation or the entry of _____, and shall prevent the escape of sparks or molten particles.

fibers/flyings

Luminaires for fixed lighting installed in Class II, Division 2 locations shall be protected from physical damage by a suitable _____.

guard or by location

Luminaires installed in Class II, Division 1 locations shall be protected from physical damage by a suitable _____.

guard or by location

In Class II, Division 1 locations, switches, circuit breakers, motor controllers, and fuses, including pushbuttons, relays, and similar devices shall be provided with enclosures that are _____.

identified for the location

Where LFMC is used in a Class III location as permitted in 503.10, it shall _____.

include an equipment bonding jumper of the wire type in accordance with 250. 102

If remote-control, signaling, and power-limited circuits are installed in a raceway that is subjected to different temperatures, and where condensation is known to be a problem, the raceway shall be filled with an approved material that will prevent the circulation of warm air to a colder section of the raceway. An explosionproof seal ___

isn't required for this purpose

Luminaires installed in Class II, Division 1 locations shall be identified for the location and shall be clearly marked to indicate the _____.

maximum wattage and type of lamps for which they are designed

insulated conductors used in wet ...

moisture impurvious w-2

Power-supply conductors and Class 1 circuit conductors can occupy the same cable, enclosure, or raceway _____

only where the equipment powered is functionally associated

The purpose of packing fiber in a sealing fitting is to ____.

provide a dam to contain the sealing compound until it hardens

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

rating of the branch circuit overcurrent device

Since Class 3 control circuits permit higher allowable levels of voltage and current than Class 2 circuits, additional _____ are specified to provide protection against the electric shock hazard

safeguards

Pendant luminaires installed in Class II, Division 1 locations shall be suspended by threaded RMC or steel IMC conduit stems, by chains with approved fittings, or by other approved means. Stems shall be provided with _____ or other effective means to prevent loosening.

set-screws

Luminaires in Class III locations exposed to physical damage shall be protected by a(n) _____ guard.

suitable

A branch circuit is best described as ____.

the circuit conductors between the final overcurrent device protecting the circuit and the outlet(s)

the normal location to provide over current protection of a ciruit

the conductor recieved its supply

Class 2 cables identified for future use shall be marked with a tag of sufficient durability to withstand _____.

the environment involved

Raceways permitted as a wiring method in Class II, Division 1 locations include _____.

threaded RMC and steel IMC

In Class II locations, a permitted method of bonding is the use of bonding jumpers with proper fittings.

true

The service or feeder ratings addressed by 310.15(B)(7) are based on the standard ampacity ratings from 240.6(A)

true

no connector shall be used where the oporating temp that designated for the type of insulating conductor

true

when determining the number of current carrying conductors a grounding or bonding conductor shall not be counted.

true

an acceptable method of indentifying grounded conductors is by tagging or marking them

white

When rigid metal conduit is required in hazardous locations, the threads must be cut at ____.

¾" taper per foot


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