Journeyman Electrician

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Determine the conductor ampacity given the following related information: 1.Conductors are size 500 kcmil copper -conductor insulation is THWN -eight (8) current-carrying conductors are in the raceway -ambient temperature is 125 deg. F 2.Conduit length is 50 feet 3.Installation is a wet location

178.2 amperes

When driving a ground rod and solid rock is encountered, the ground rod is permitted to be buried in a trench at LEAST _____ deep.

30 inches

What is the MINIMUM size copper SE cable with type THHW insulation that may be used as ungrounded (phase) service-entrance conductors for a 150-ampere rated, 120/240-volt, single-phase residential service?

1 AWG

All motors shall be considered as _____ unless the nature of the apparatus it drives is such that the motor will not operate continuously.

continuous duty

A single-gang, 1 in. deep, Type FS box is permitted to house no more than _____ size 12 AWG conductors.

six

A disconnecting means shall be provided on the supply side of all fuses in circuits having a voltage of at LEAST _____ to ground.

150 volts

Determine the MAXIMUM number of size 1 AWG XHHW compact conductors permitted in a trade size 3 in., rigid Schedule 40 PVC conduit more than 24 inches long.

21

A 208-volt, 3-phase, 50 hp, squirrel-cage, continuous-duty, ac motor has a full-load running current rating of _____?

143 amperes

Enclosures in a Class I, Division 1 location containing components that have arcing devices must have an approved seal located within at LEAST _____ of each conduit run entering or leaving such enclosures.

18 inches

A listed _____ shall be installed in or on all emergency systems switchboards and panelboards?

surge protective device (SPD)

The NEC defines a continuous load to be a load where the maximum current on the circuit is expected to continue for at LEAST____ hours or more?

three

Where exceptions are not to be considered, service conductors installed as open conductors shall have a clearance of NOT less than _____ from windows that are designed to be opened, porches, doors or balconies.

3 feet

What is the MAXIMUM distance that a disconnect switch is permitted to be located from the operator's station for a portable carnival ride?

6 feet

When installing wiring for sensitive electronic equipment, the MAXIMUM voltage to ground is required to be _____ .

60 volts

When determining the required ampacity of the branch-circuit conductors to supply a 3-phase, continuous-duty ac motor, current values given on _____ shall be used.

Table 430.250 of the NEC

According to the NEC® which of the following statements is true about installing listed or labeled equipment?

The equipment shall be installed in accordance with the instructions.

In dwelling units, all 125-volt, single-phase, 15- or 20-ampere receptacle outlets installed within six (6) feet of the outside edge of a sink in a laundry room shall be provided with _____.

both GFCI protection and AFCI protection

For an ac system operating at less than 1000 volts, a main bonding jumper shall connect the grounded conductor(s) to _____.

each service disconnecting means enclosure

In regard to residential occupancies, the branch-circuits supplying 125-volt, single-phase, 15- or 20-ampere receptacles in a garage _____.

shall not supply any other outlets outside of the garage

Standard trade size 2 in. rigid Schedule 40 polyvinyl chloride conduit (PVC), shall be supported at LEAST every _____.

5 feet

For other than one-and two-family dwellings, when building a new electrical service, at least one (1) 125-volt, single-phase, 15- or 20-ampere-rated receptacle outlet shall be located within at LEAST _____ of the electrical service equipment?

50 feet

When connecting to luminaires, trade size 3/8 in. flexible metal conduit (FMC) is permitted to enclose tap conductors, provided the length of the FMC does NOT exceed _____ ?

6 feet

Direct-buried conductors emerging from grade shall be protected by raceways or covers up to at LEAST _____ above finished grade.

8 feet

Which of the following methods is an acceptable marking for the grounding pole on a grounding type receptacle?

A green colored hexagonal headed or shaped terminal screw.

Class 3 single conductors shall NOT be smaller than _____.

18 AWG

When intermediate metal conduit (IMC) is threaded in the field, a standard cutting die with a _____ taper per foot shall be used.

3/4 in.

Plate grounding electrodes shall be installed NOT less than _____ below the surface of the earth.

30 inches

Where exceptions are not applicable, when a feeder supplies a continuous load of 240 amperes, the overcurrent protection device protecting this circuit shall have a rating of at LEAST _____?

300 amperes

What is the MINIMUM size equipment grounding conductor required for a 5 hp, 3-phase, 208-volt motor having 20-ampere rated overload protection and branch-circuit, short-circuit and ground-fault protection rated 30-amperes?

10 AWG

Where a size 4 AWG or larger conductor enters a panelboard, which of the following must be provided?

An insulated bushing.

The interior of enclosures or raceways installed underground shall be considered as a _____ location?

dry

Branch-circuit conductors supplying a fixed storage-type electric water heater with a capacity of 120 gallons or less, shall have an ampacity of NOT less than _____ of the full-load current of the water heater.

125 percent

Branch-circuit conductors supplying more than one motor shall have an ampacity of at LEAST_____ of the full-load current rating of the highest rated motor in the group, and 100 percent of the full-load current rating of the other motor(s) in the group.

125 percent

Outside open conductors of not over 1000 volts shall have a clearance of NOT less than _____ from signs, chimneys, and television antennas.

3 feet

What is the MAXIMUM length of a flexible cord that may be used for a recirculating pump motor on a swimming pool at a dwelling?

3 feet

Grounding electrodes made of pipe or conduit shall NOT be smaller than _____ electrical trade size.

3/4 in.

A 30 hp, 480-volt, 3-phase wound-rotor, ac motor has a full-load running current rating of _____.

40 amperes

A single-phase, 125-volt receptacle installed to serve a washing machine in the laundry room of a dwelling unit must be installed within at LEAST ______ of the intended location of the appliance?

6 feet

Where exposed Type NM cable passes through a floor, the cable shall be enclosed in an approved conduit extending at LEAST _____ above the floor.

6 inches

Conduit nipples not over 24 inches in length may be filled to a MAXIMUM of _____ of their cross-sectional area.

60 percent

In general, which of the following receptacle outlets in a commercial kitchen are required by the NEC® to be GFCI protected?

All 125-volt, 15- or 20-ampere receptacles.

Where a circuit breaker serves as the controller for a motor, and the motor is not in sight of the breaker, the NEC® requires which of the following?

The circuit breaker is to be capable of being locked in the open position.

Before demand factors are taken into consideration for commercial buildings, general-purpose receptacle loads are to be computed at NOT less than _____ per outlet.

180 VA

When grounding the structural reinforcing steel of a swimming pool, what is the smallest size grounding conductor permitted for this installation?

8 AWG

Where a single-phase, 240-volt air-conditioning unit has a full-load current rating of 35 amperes marked on the nameplate, what is the MINIMUM size 75C copper conductors required to supply the air-conditioning unit?

8 AWG

For enclosing a mobile home supply cord, what is the MAXIMUM trade size conduit permitted between the branch circuit panelboard of a mobile home and the underside of a mobile home floor?

1 1/4 in.

The NEC considers the area around the motor fuel dispensing pumps of a service station to be a hazardous location. This area extends a height of 18 inches above grade, and up to a distance from the enclosure of the outdoor motor fuel dispensing pumps of ____.

20 feet

When conductors are installed in a conduit or tubing nipple of _____ or less in length, the ampacity adjustment factors for more than three (3) current-carrying conductors in the raceway are not required to be applied.

24 inches

Where an ac electrical service is supplied with four (4) parallel sets of size 500 kcmil aluminum ungrounded conductors, what is the MINIMUM size copper grounding electrode conductor required when connected to the concrete encased reinforcing building steel?

3/0 AWG

When terminating conductor sizes 14 AWG through 1 AWG on circuit breakers, the conductors shall be considered to have a temperature rating of ______, unless the circuit breakers are listed and marked otherwise.

60C

Where an 80-ampere, 240-volt, single-phase load is located 200 feet from a panelboard and is supplied with size 3 AWG copper conductors with THWN insulation, what is the approximate voltage-drop on the circuit? (K = 12.9)

7.84 volts

Which of the following wiring methods is/are approved for use for fixed wiring in an area above Class I locations in a commercial garage?

All of the above

Determine the MINIMUM trade size electrical metallic tubing (EMT) required to enclose eight (8) size 6 AWG copper conductors with THHW insulation, when installed in a 50 foot conduit run?

1 1/4 in.

Disregarding exceptions, all 3-phase, 4-wire, 480Y/277 volt, electrical services, require ground-fault protection for each service disconnecting means when rated for at LEAST _____ or more?

1,000 amperes

In indoor areas where walls are frequently washed, such as laundries or car washes, metallic conduit and metallic panelboards shall be mounted with a MINIMUM _____ space between the wall and conduit or panelboard when the equipment is installed exposed?

1/4 in.

What is the MINIMUM size wire type equipment grounding conductor for a 50 ampere branch circuit as required by the NEC®?

10 AWG

Where a motor of more than 1 horsepower has a temperature rise of 50 deg. C indicated on the nameplate, for the purposes of selecting the overload device, this device shall be selected to trip at NO more than _____ of the motor's full-load ampere rating. (Assume modification of this value is not necessary.)

115 percent

Liquidtight flexible metal conduit (LFMC) shall be securely fastened WITHIN _____ of each box or other conduit termination?

12 inches

Determine the MAXIMUM allowable current-carrying capacity of four (4) size 1/0 AWG THW copper current-carrying conductors installed in a common raceway with an ambient temperature of 86 degrees F?

120 amperes

A branch circuit supplied by size 12 AWG conductors is a _____ rated branch circuit when protected by a 15-ampere circuit breaker?

15 ampere

Information technology equipment shall be permitted to be connected to a branch circuit by a listed power-supply cord having a length NOT to exceed _____.

15 feet

Underground wiring is not permitted under a permanently installed swimming pool or within _____ of the pool, unless the wiring is supplying the associated pool equipment.

5 feet

Where a trade size 1/2 in. rigid metal conduit (RMC) is installed in a Class I location and a 1/2 in. conduit seal is required, the MINIMUM thickness of the sealing compound shall NOT be less than _____?

5/8 in.

Infrared commercial and industrial heating appliances shall have overcurrent protection NOT exceeding _____?

50 amperes

All 125-volt, single-phase, 15- or 20-ampere receptacle outlets installed within at LEAST _____ of the outside edge of a dwelling unit bathtub or shower stall require GFCI protection.

6 feet

Household-type appliances with surface heating elements having a MAXIMUM demand of more than _____ shall have its power supply subdivided into two (2) or more circuits.

60 amperes

What is the MAXIMUM overcurrent protection allowed for the protection of resistance-type electric space heating equipment?

60 amperes

A single-phase, 240-volt, 15 kVA standby generator may be loaded to a MAXIMUM of _____ per line.

62.50 amperes

In regard to electric space heating equipment, heating cables shall be furnished complete with factory-assembled nonheating leads at LEAST _____ in length.

7 feet

What MAXIMUM percent of a metal wireway cross-section may be occupied by splices, taps and conductors at any point?

75 percent

Given: You have determined a conductor has a computed allowable ampacity of 75 amperes. What is the MAXIMUM standard ampere rating of the overcurrent protection device the NEC® permits to protect this circuit where this is not a motor circuit or part of a multioutlet branch circuit supplying more than one receptacle?

80 amperes

When ambient temperature is not a factor, a size 8 AWG single copper conductor with type FEPB insulation, installed in free air, will have a MAXIMUM allowable ampacity of _____?

80 amperes

In industrial establishments, where sizes 1/0 AWG through 4/0 AWG single conductor cables are installed in ladder type cable tray, the MAXIMUM allowable rung spacing for the cable tray shall be _____ .

9 inches

In a health care facility, a patient bed location in a critical care area is required to have which of the following?

Fourteen single receptacles or seven duplex receptacles.

Which of the following listed types of batteries is NOT permitted for use as a source of power for emergency systems?

automotive

The purpose of an intersystem bonding termination is to provide a means for connecting _____ to the grounding electrode system.

bonding conductors for communications systems

Where a submersible pump is housed in a metal well casing, the well casing shall be _____ the pump circuit equipment grounding conductor?

connected to

Given: A metal junction box has a volume of 27 cubic inches and contains a total of six (6) size 12 AWG conductors, no grounding conductors, devices or fittings are contained in the box. Additional wires of size 10 AWG need to be added in the box. What is the MAXIMUM number of size 10 AWG conductors may be added to this box?

five

Determine the MAXIMUM number of size 14 AWG THHN conductors permitted to be installed in a trade size 3/8 in. flexible metal conduit (FMC) that contains a bare size 14 AWG grounding conductor, when the FMC has external fittings.

four

In an underground installed rigid polyvinyl chloride conduit (PVC) system that consist of 50 feet length between pulling points, what is the MAXIMUM number of bends this run may have?

four (4) - 90 degree

Three-way and four-way switches shall be wired so that all switching is done _____.

only in the ungrounded circuit conductor

The service disconnecting means for each electrical service shall consist of NOT more than _____ switches or circuit breakers, mounted in a single enclosure or in a group of separate enclosures.

six

Liquidtight flexible metallic conduit (LFMC) shall NOT be used _____.

where subject to physical damage

What is the MAXIMUM number of times a grounding electrode conductor is permitted to be spliced by use of listed split-bolt connectors?

none

For the purpose of determining conductor fill in a device box, a single-pole switch and/or a three-way switch is counted as equal to _____ conductor(s), based on the largest conductor connected to the switch.

two

In guest rooms of hotels, motels, and sleeping rooms of dorms a MINIMUM of _____ general purpose receptacles installed in the room is/are required to be readily accessible.

two

Where the motor controller also serves as a disconnecting means, it shall open all _____ conductors to the motor.

ungrounded

At the time of installation, grounded (neutral) conductors larger than size 6 AWG may be identified at its terminations by _____ colored phase tape.

white

When conductors of different systems are installed in the same raceway, one system grounded conductor shall be white or gray. The other system grounded conductor shall be _____ .

white or gray with an identifying colored stripe that is not green

Electrically heated floors in bathrooms, kitchens, and in hydromassage bathtub locations shall be _____.

GFCI protected

Class _____ hazardous locations are those in which flammable liquid-produced vapors, or combustible liquid-produced vapors are or may be present in the air in quantities sufficient to produce explosive or ignitible mixtures?

I

Class _____ locations are those that are hazardous because of the presence of easily ignitible fibers or where materials producing combustible flyings are handled, but in which such fibers/flyings are not likely to be in suspension in the air in quantities sufficient to produce ignitible mixtures.

III

Which one of the following listed conduits does the NEC® permit to enclose conductors supplying wet-niche underwater pool luminaires?

Schedule 40 rigid polyvinyl chloride conduit (PVC)

Conductors with ______ insulation have a greater ampacity when used in a dry location compared to when used in a wet location.

THHW

According to the National Electrical Code®, what are the three (3) mandatory separate branches of the hospital essential electrical system?

The life safety branch, the critical branch and the equipment branch.

Disconnect switch enclosure installed in a Class II, Division 2 location shall be listed as _____?

dusttight

Where a pull box to be installed will contain conductors of size 4 AWG and larger, and a straight pull of the conductors is to be made, the length of the box shall NOT be less than ____times the trade diameter of the largest conduit entering the box.

eight

The ampacity of a conductor is defined by the NEC to be the maximum current, in amperes, a conductor can carry continuously under the conditions of use without exceeding ______?

it's temperature rating

When conductors or cables are installed in raceways exposed to direct sunlight on or above a rooftop and within at LEAST _____ of the rooftop, a temperature adder must be applied to the applicable correction factors of Table 310.15(B)(2)(a) to determine the allowable ampacity of the conductors.

36 inches

Where size 14 AWG branch-circuit conductors protected by a 15-ampere rated circuit breaker supplies three (3) 20-ampere rated duplex receptacles, this branch circuit _____ .

is not in compliance with the NEC because the receptacles have a 20-ampere rating


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