Article 110- Requirements for Electrical Installations

Where equipment operating at 1,000V, nominal, or less to ground and likely to require examination, adjustment, servicing, or maintenance while energized is required by installation instructions or function to be located in a space with limited access, and where equipment is installed above a lay-in ceiling, there shall be an opening not smaller than _____.

22 in. x 22 in

A minimum working space depth of _____ ft to live parts of equipment operating at 277 volts-to-ground is required where there are exposed live parts on one side and no live or grounded parts on the other side.

3

Concrete, brick, or tile walls are considered _____, as applied to working space requirements.

3 1/2

The term "rainproof" is typically used in conjunction with enclosure type(s) _____.

3R and 3RX

All switchboards, switchgear, panelboards, 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, shall be dedicated to the electrical installation.

6

The minimum height of dedicated equipment space for motor control centers installed indoors is _____ ft above the enclosure, or to the structural ceiling, whichever is lower.

6

For large equipment that contains overcurrent devices, switching devices, or control devices, there shall be one entrance to and egress from the required working space not less than 24 in. wide and _____ ft high at each end of the working space.

6 1/2

Where equipment operating at 1,000V, nominal, or less to ground and likely to require examination, adjustment, servicing, or maintenance while energized is required by installation instructions or function to be located in a space with limited access, all enclosure doors or hinged panels shall be capable of opening a minimum of _____ degrees.

90

General requirements for the examination and approval, installation and use, access to and spaces about electrical conductors and equipment; enclosures intended for personnel entry; and tunnel installations are within the scope of _____.

Article 110

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

_____ at other than dwelling units shall be legibly field marked with the available fault current, include the date the fault-current calculation was performed, and be of sufficient durability to withstand the environment involved.

Service equipment

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

Electrical equipment rooms or enclosures housing electrical apparatus that are controlled by a lock(s) shall be considered _____ to qualified persons.

accessible

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

achieve

Where caution, warning, or danger signs or labels are required by this Code, the label marking shall warn of the hazards using effective _____.

any combination of words, colors, or symbols

The conductors and equipment required or permitted by this Code shall be acceptable only if _____.

approved

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

The temperature rating associated with the ampacity of a _____ shall be selected and coordinated so as not to exceed the lowest temperature rating of any connected termination, conductor, or device.

conductor

Where electrical conductor material is not specified, the sizes given in the NEC shall apply to _____ conductors.

copper

Conductor terminal and splicing devices shall be _____ for the conductor material and they shall be properly installed and used.

identified

Equipment not _____ for outdoor use or identified for indoor use such as "dry locations" or "indoor use only", shall be protected against damage from the weather during construction.

identified

Tightening torque values for terminal connections shall be as indicated on equipment or in installation instructions provided by the manufacturer. An approved means shall be used to achieve the _____ torque value.

indicated

Field markings of maximum available fault current at a service are not required in

industrial installations where conditions of maintenance and supervision ensure that only qualified persons service the equipment.

Listed or labeled equipment shall be

installed and used in accordance with any instructions included in the listing or labeling.

The NEC requires that electrical equipment be _____.

installed in a neat and workmanlike manner

Where equipment operating at 1,000V, nominal, or less to ground and likely to require examination, adjustment, servicing, or maintenance while energized is required by installation instructions or function to be _______.

located in a space with limited access, the space in front of the enclosure shall comply with the depth requirements of Table 110.26(A)(1).

Unless identified for use in the operating environment, no conductors or equipment shall be _____ having a deteriorating effect on the conductors or equipment.

located in damp or wet locations, exposed to fumes, vapors, liquids, or gases, and exposed to excessive temperatures

Reconditioned equipment shall be marked with the _____ by which the organization responsible for reconditioning the electrical equipment can be identified, along with the date of the reconditioning.

name, trademark, and/or descriptive marking

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.

nominal system voltage and incident energy levels, arc-flash boundaries, and minimum required levels of personal protective equipment

For equipment rated 800A or more that contains overcurrent devices, switching devices, or control devices; and where the entrance to the working space has a personnel door(s) less than 25 ft from the nearest edge of the working space, the door shall _____.

open in the direction of egress and be equipped with listed panic hardware

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

orange

The ______, and other characteristics of the circuit to be protected shall be selected and coordinated to permit the circuit protective devices used to clear a fault to do so without extensive damage to the electrical equipment of the circuit.

overcurrent protective devices, total impedance, and equipment short-circuit current ratings

Internal parts of electrical equipment, including busbars, wiring terminals, insulators, and other surfaces, shall not be damaged or contaminated by foreign materials such as _____, or corrosive residues.

paint and plaster, cleaners, and/or abrasives

Fiber optic cables installed exposed to _____, or other contaminants may result in an undetermined alteration of optical fiber cable properties.

paint or plaster, cleaners or abrasives, and/or corrosive residues

As applied to electrical equipment, the term "reconditioned" may be interchangeable with the term(s) "_____."

rebuilt, refurbished, and/or remanufactured

When modifications to the electrical installation occur that affect the maximum available fault current at the service, the maximum available fault current shall be verified or _____ as necessary to ensure the service equipment ratings are sufficient for the maximum available fault current at the line terminals of the equipment.

recalculated

Product testing, evaluation, and listing (product certification) shall be performed by _____.

recognized qualified electrical testing laboratories

Reconditioned equipment shall be identified as "reconditioned" and the original listing mark _____.

removed

NFPA 70E, Standard for Electrical Safety in the Workplace, provides guidance, such as determining severity of potential exposure, planning safe work practices including establishing an electrically _____ work condition, arc flash labeling, and selecting personal protective equipment.

safe

Some cleaning and lubricating compounds can cause _____.

severe deterioration of many plastic materials used for insulating and structural applications in equipment.

Working space shall not be used for _____.

storage

Only wiring methods recognized as _____ are included in this Code.

suitable

Reconditioned equipment original listing mark may include

the mark of the certifying body and not the entire equipment label.

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

the purpose is evident

Access and _____ shall be provided and maintained about all electrical equipment to permit ready and safe operation and maintenance of such equipment.

working space

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 workspace is _____.

4 ft

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 _____.

110.26(A)

For large equipment that contains overcurrent devices, switching devices, or control devices, there shall be one entrance to and egress from the required working space not less than ______ in. wide.

24

The working space in front of the electric equipment shall not be less than _____ in. wide, or the width of the equipment, whichever is greater.

30

Equipment associated with the electrical installation can be located above or below other electrical equipment within their working space when the associated equipment does not extend more than _____ in. from the front of the electrical equipment.

6

The minimum height of working spaces above electrical equipment, switchboards, panelboards, or motor control centers operating at 1,000V, nominal, or less and likely to require examination, adjustment, servicing, or maintenance while energized shall be ______ or the height of the equipment, whichever is greater, except for service equipment or panelboards in existing dwelling units that do not exceed 200A.

6 1/2 ft

Conductors shall have their ampacity determined using the _____ column of Table 310.16 for circuits rated over 100A, or marked for conductors larger than 1 AWG, unless the equipment terminals are listed for use with higher temperature-rated conductors.

75

For circuits rated 100A or less, when the equipment terminals are listed for use with 75°C conductors, the _____ column of Table 310.16 shall be used to determine the ampacity of THHN conductors.

75°C

The dedicated space above a panelboard extends to a dropped or suspended ceiling, which is _____.

NOT considered a structural ceiling.

Conductor sizes are expressed in American Wire Gage (AWG) or in _____.

circular mils

When service equipment is required to be field marked with the available fault current, the value of available fault current for use in determining appropriate minimum short-circuit current ratings of service equipment is available from _____ in published or other forms.

electric utilities

Working space distances for enclosed live parts shall be measured from the _____ of equipment or apparatus, if the live parts are enclosed.

enclosure or opening

Working space is required for equipment operating at 1,000V, nominal, or less to ground and likely to require _____ while energized.

examination, adjustment, and servicing or maintenance

The area above the dedicated space required by 110.26(E)(1)(a) is permitted to contain _____.

foreign systems, provided protection is installed to avoid damage to the electrical equipment from condensation, leaks, or breaks in such foreign systems.

When normally enclosed live parts are exposed for inspection or servicing, the working space, if in a passageway or general open space, shall be suitably _____

guarded

Equipment intended to interrupt current at fault levels shall __________.

have an interrupting rating at nominal circuit voltage at least equal to the current that is available at the line terminals of the equipment.

Illumination shall be provided for all working spaces about service equipment, switchboards, switchgear, panelboards, or motor control centers _____.

installed indoors

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

short circuits, ground faults, and connections to the earth

Examples of approved means of achieving terminal connection torque values include _____.

the use of torque tools or devices such as shear bolts or breakaway-style devices with visual indicators that demonstrate the proper torque has been applied.

For large equipment that contains service disconnecting means installed in accordance with 230.71 where the combined ampere rating is _____ or more and over 6 ft wide, there shall be one entrance to and egress from the required working space not less than 24 in. wide and 6 1/2 ft high at each end of the working space

1,200A

In other than dwelling units, in addition to requirements for field or factory marking of equipment to warn qualified persons of potential electric arc-flash hazards, a permanent label shall be field or factory applied to service equipment rated _____ or more.

1,200A

Where equipment operating at 1,000V, nominal, or less to ground and likely to require examination, adjustment, servicing, or maintenance while energized 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

The minimum working space on a circuit for equipment operating at 750 volts-to-ground, with exposed live parts on one side and grounded parts on the other side of the working space, is _____ ft.

4

The disconnecting means is required to be _________.

able to be locked in the open position by the NEC

Conductors of dissimilar metals shall not be intermixed in a terminal or splicing connector where physical contact occurs between dissimilar conductors (such as _____ or aluminum and copper-clad aluminum), unless the device is identified for the purpose and conditions of use.

copper

Electrical equipment such as switchboards, switchgear, panelboards, industrial control panels, meter socket enclosures, and motor control centers, that are in other than dwelling units, and are likely to require _____ while energized, shall be field or factory marked to warn qualified persons of potential electric arc-flash hazards.

examination, adjustment, and/or servicing or maintenance

All switchboards, switchgear, panelboards, and motor control centers shall be located in dedicated spaces and protected from damage, and outdoor installations shall be _____.

installed in identified enclosures, protected from accidental contact by unauthorized personnel or by vehicular traffic, and protected from accidental spillage or leakage from piping systems

The NEC requires tested series-rated installations of circuit breakers or fuses to be

legibly marked in the field to indicate the equipment has been applied with a series combination rating.

The minimum working space on a circuit for equipment operating at 120 volts-to-ground, with exposed live parts on one side and no live or grounded parts on the other side of the working space, is _____ ft.

3

All switchboards, panelboards, and motor control centers shall be _____.

located in dedicated spaces and protected from damage

In judging equipment for approval, considerations such as _____ shall be evaluated

mechanical strength, wire-bending space, and arcing effects

NFPA 70E, Standard for Electrical Safety in the Workplace, provides guidance, such as determining severity of potential exposure, planning safe work practices, arc-flash labeling, and selecting _____.

personal protective equipment

The manufacturer's name, trademark, or other descriptive markings by which the organization responsible for the product can be identified shall be _____.

placed on all electrical equipment

Cables and conductors installed exposed on the surfaces of ceilings and sidewalls shall be secured by hardware including straps, staples, cable ties, hangers, or _____ fittings designed and installed so as not to damage the cable.

simila

Connection of conductors to terminal parts shall ensure a thoroughly good connection without damaging the conductors and shall be made by means of _____.

splices, joints, and free ends of conductors