Quarter 4 Exam

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What is the neutral current for a 4-wire, 120/208v circuit, where L1=20A, L2=20A, and L3 = 20A

0A

The required working space for chess to live parts of equipment operating at 300 volts-to-ground, where there are exposed live parts on one side and grounded parts on the other side, is ______ ft.

3 1/2 ft

A minimum working space depth of _____ ft to live parts of equipment operating at 277 volts-to-ground is required where there are exposed to live parts.

3 ft

Were equipment operating at 1000 V nominal or less to ground and likely to require examination adjustment servicing or maintenance will energize is required by installation instructions or function to be located in a space with limited access. The width of the working space shall be the width of the equipment enclosure, or a minimum of ____ in, whichever is greater.

30 inches

The required working space for access to live parts of equipment operating at 300 volts-to-ground, where there are exposed live parts on both sides of the workplace is _______ ft.

4 feet

Live parts of electrical equipment operating at _________, nominal shall be gauged against accidental contact by approved enclosures or by suitable permanent, substantial partitions or screens arranged so that only qualified persons have access to the space within reach of the live parts.

50V to 1000V

Conductor ampacity shall be determined using the ________ column of Table 310.15

60 degrees Celsius

"___________" means acceptable to the authority having jurisdiction.

Approved

The _______ has the responsibility for deciding on the approval of equipment and materials.

Authority Having Jurisdiction

Wires are considered ______________ if rendered inaccessible by the structure or finish of the building.

Concealed

To discharge a capacitor, all that is required is a(n) ________ path between the terminals of the capacitor. The free electrons on the negative plate will then flow through the external circuit to the positive plate.

Conductive

A ___________ location may be temporarily subject to dampness and wetness.

Dry

When protecting equipment against damage from the weather during construction, minimum _______ provisions provided in the IBC

Flood

The NEC is ________?

For the practical safeguarding of persons and property

Equipment or materials included in a list published by a testing laboratory acceptable to the authority having jurisdiction are said to be "_____________"

Listed

All switchboards, panel boards, and motor control censors shall be ___________.

Located in dedicated spaces, and protected from damage.

The authority having jurisdiction has the responsibility for ___________.

Making interpretations of rules, deciding upon the approval of equipment and materials, waiving specific requirements in the Code and permitting alternate methods and material if safety is maintained.

Wooden plugs driven into holes in _______ or similar materials shall not be used for securing electrical equipment.

Masonry, Concrete, and Plaster

Conductors normally used to carry currents shall be _________ unless otherwise provided in this NEC.

Of copper and aluminum

The _______ of an AC Generator contains the electromagnetic field, which cuts through the stationary conductor coils.

Rotor.

(T/F) The minimum height of working spaces of that electrical equipment, switchboards, panel boards or motor control centers operating at 1000 V nominal or less and likely to require examination adjustment servicing or maintenance while energize shall be 6 1/2 feet or the height of the equipment which ever is greater except for service equipment or panel boards in existing dwelling units that do not exceed 200 A

True

(T/F) When conductors carrying current in the same direction are brought together, the electromagnetic fields attempt to push the conductors together.

True

Utilities may be subject to compliance with codes and standards covering their regulated activities as adopted under government Liam or regulation

True

Entrances to rooms and other guarded locations containing exposed live parts shall be marked with conspicuous ________ forbidding unqualified persons to enter.

Warning Signs

A single receptacle is a single contact device with no other contact device on the same ___________.

Yoke

Unused openings other than those intended for the operation of equipment, intended for mounting purposes, or permitted as part of the design for listed equipment shall be ________.

closed to afford protection substantially equivalent to the wall of the equipment

Working space shall not be used for ______.

storage

Each disconnecting means shall be legibly marked to indicate its purpose unless located and arranged so __________.

the purpose is evident

All switchboards, switch gear, panel boards, 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, shale be dedicated to the electrical installation.

6 feet.

For equipment rated 1200 A or more and over 6 feet wide that contains overcurrent devices switching devices or control devices there Shelby one entrance to and egress from the required working space not less than 24 inches wide and _______ ft high at each end of the working space.

6.5 feet

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

Capable of being removed or exposed without damaging the building structure or finish, or not permanently closed in by the structure or finish of the building is known as "_____________".

Accessible (as applied to wiring methods)

Separately installed pressure connectors shall be used with conductors at the _____ not exceeding the ampacity at the listed and identified temp rating of the connector.

Ampacities

Compliance with the provisions of the NEC will result in ___________.

An electrical system essentially free from hazard.

Installations of communications equipment that are under the exclusive control of communications utilities, and located outdoors or in building spaces used exclusively for such installations ________ covered by the NEC.

Are not

Nonmandatory informative annexes contained in the back of the NEC book are____________.

For information only, and not enforceable as requirement of the NEC.

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

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 _____.

Installed in identified enclosures, protected from accidental contact by unauthorized personnel or by vehicular traffic., protected from accidental spillage or leakage from piping systems. (All of these)

Ohm's law demonstrates the relationship between circuit ________.

Intensity, EMF, Resistance (All of these)

The NEC covers the installation of ______ for public and private premises, including buildings, structures, mobile homes, RVs, and floating buildings.

Optical Fiber Cables, Electrical Equipment, and Race Ways

On a 4-wire, delta-connected system where the midpoint of one phase winding is grounded, only the conductor or bus bar having the higher phase voltage-to-ground shall be durably and permanently marked by an outer finish that is ________ in color.

Orange

When the NEC uses "__________" it means the identified actions are allowed but not required, and they may be options or alternative methods.

Shall be permitted

Wiring shall be installed so that the completed system will be free from ________, other than as required or permitted elsewhere in the NEC.

Short circuits, ground faults, connections to the earth

Which of the following systems shall be installed and removed in accordance with the NEC requirements?

Signaling conductors, equipment, and raceways communications conductors, equipment, and raceways Electrical conductors, equipment, raceways. (ALL OF THESE)

(T/F) 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

(T/F) NFPA 70E, Standard for electrical safety in the workplace, provides guidance for working space about electrical equipment, such as determining severity of potential exposure, planning safe work practices, arc-flash labeling, and selecting personal protective equipment.

True

(T/F) Soldered splices shall first be spliced or joined so as to be mechanically and electrically secure without solder and then be soldered.

True

A "raceway is an enclosed channel designed expressly for the holding of wires, cables, or bus bars, with additional functions as permitted in the code.

True

Communications wiring such as telephone, antenna, and CATV wiring within a building shall not be required to comply with the installation requirements of Chapters 1 through 7, except where specifically referenced in chapter 8.

True

Acceptable industry practices for equipment labeling are described in NFPA 70E, standard for electrical safety in the workplace. This standard provides specific criteria for developing arc-flash labels for equipment that provides ________, and so forth.

nominals system voltage and incident energy levels, arc-flash boundaries, and minimum required levels of personal protective equipment (all of these).


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