Article 110 – Requirements for Electrical Installations Practice Test

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• In industrial installations where maintenance and supervision ensure only qualified persons service the equipment, field marking of maximum available fault current is:
• For circuits rated 100A or less, when the equipment terminals are listed for use with 75 degrees Celsius conductors, the _________ column of Table 310.16 shall be used to determine the ampacity of THHN conductors.
• Conductor terminals and splicing devices shall be identified for the conductor material. Which term completes this requirement?
• For circuits over 100A and conductors larger than 1 AWG, which column of Table 310.16 is used to determine ampacity if the terminals are not listed for higher temperature-rated conductors?
• 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.
• Which term describes the maximum current a conductor can carry at a specified temperature rating?
• What is the primary reason for proper ventilation around electrical equipment?
• What is the consequence of a damaged enclosure on compliance with Article 110?
• What should be installed in areas vulnerable to physical damage to prevent contact or impact?
• What is the primary purpose of providing working space around electrical equipment?
• Which elements must be coordinated to clear a fault without extensive damage to electrical equipment?
• What is the primary purpose of arc-flash labels as described in the material?
• Unless identified for use in the operating environment, no conductors or equipment shall be located in
• What is the purpose of adequate clearance around electrical equipment?
• Are electrical installations allowed to block egress or walkways?
• The available fault current value used for determining minimum short-circuit ratings is obtained from which source?
• For outdoor installations, the space extending from grade to a height of how many feet above the equipment must be dedicated to the electrical installation?
• The NEC requires that electrical equipment shall be ______.
• Which body performs product testing, evaluation, and listing in the context of electrical equipment compliance?
• What is the impact of Article 110 requirements on maintenance in high-traffic areas?
• Which statement best describes field marking content in non-dwelling locations?
• What factors affect where electrical equipment is placed in high-traffic areas?
• The conductors and equipment required or permitted by this code shall be acceptable only if
• What typical content is found in installation instructions accompanying electrical equipment per Article 110?
• Why are heat dissipation clearances around equipment important?
• What is the minimum working space in feet 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?
• For equipment operating at 300 volts-to-ground with exposed live parts on one side and grounded parts on the other, the minimum working space is how many feet?
• Which personnel should have access to electrical equipment for operation and maintenance?
• When evaluating changes in equipment usage under Article 110, what must be verified?
• Reconditioned equipment shall be marked with the name, trademark, or other descriptive marking (any of these). What additional information is included?
• In non-dwelling units, service equipment rated 1,200 A or more must have a permanent label field or factory applied. What rating triggers this requirement?
• When modifications affect the maximum available fault current, the maximum available fault current shall be verified or recalculated as necessary to ensure the service equipment ratings are adequate.
• How does Article 110 address equipment used in hazardous locations in terms of listing?
• What is the purpose of the working space requirement in Article 110?
• What must be true when installing equipment in damp or wet locations?
• The working space in front of the electric equipment shall not be less than how many inches wide, or the width of the equipment, whichever greater?
• The combined ampere rating threshold that triggers the 24 in width and 6 1/2 ft high requirement is at least ____ A.
• The dedicated space above a panelboard extends to a dropped or suspended ceiling.
• The exception to the minimum height requirement applies to service equipment or panelboards in existing dwelling units that do not exceed how many amperes?
• Working space for equipment operating at 1000 volts, nominal, or less to ground and likely to require ______________________ while energized.
• According to NEC, a disconnecting means that is required to be locked in the open position must be capable of being locked in which position(s)?
• The minimum height of working spaces about electrical equipment operating at 1,000 V nominal or less and likely to require examination while energized is which of the following?
• What is the primary purpose of field marking the available fault current on service equipment?
• Which sequence accurately reflects energizing after installation?
• In a circuit directory, which information is typically documented to support safety and maintenance?
• Fiber optic cables installed exposed to _____, or other contaminants may result in an undetermined alteration of optical fiber cable properties.
• Conductors of dissimilar metals shall not be intermixed in a terminal or splicing connector where physical contact occurs between dissimilar conductors (such as ________________ and aluminum, copper and copper-clad aluminum) Unless the device is identified for the purpose and conditions of use.
• What role does inspection play in Article 110 compliance?
• Which of the following are approved means of achieving terminal connection torque values?
• Conductor size expressions include AWG and circular mils. What does circular mils measure?
• When installing equipment outdoors, what environmental consideration is required?
• If a field modification results in the equipment not matching listing, what action is required?
• NFPA 70E, Standard for Electrical Safety in the Workplace, provides guidance, such as determining the severity of potential exposure, planning safe work practices including establishing an electrically _________ work condition, arc-flash labeling, and selecting PPE.
• Internal parts of electrical equipment shall not be damaged by foreign materials such as which of the following?
• What is the purpose of securely anchoring equipment to structural members?
• Equipment not _______ for outdoor use or identified for indoor use only such as "dry locations" or "indoor use only", shall be protected against damage from the weather during construction.
• Article 110 extends to cover general requirements for examination and approval, installation and use, access to spaces about electrical conductors and equipment; enclosures intended for personnel entry; and tunnel installations.
• Connection of conductors to terminal parts shall ensure a thoroughly good connection without damaging the conductors and shall be made by means of ___________________.
• What is the importance of labeling and markings on electrical equipment under Article 110?
• 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.
• 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 _____.
• The available fault current value supplied by electric utilities is used to determine what?
• Electrical equipment rooms or enclosures that are controlled by a lock shall be considered _____ to qualified persons.
• What is the stance on using extension cords as a primary wiring method?
• What is the primary scope of NEC Article 110?
• Conductor ampacity shall be 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.
• What is the minimum headroom required in front of panelboards?
• The following statement is true: Examples of approved means of achieving terminal connection torque values include torque tools or an experienced qualified person that can demonstrate that the proper torque has been applied.
• Which items must be selected and coordinated to permit circuit protective devices to clear a fault without extensive damage to the electrical equipment of the circuit?
• Which factor is essential for safe access during operation and maintenance?
• Why is proper ventilation and temperature control important around electrical equipment?
• How should equipment be mounted and secured to ensure safety under Article 110?
• Which of the following statements lists the correct width for the entrance and the correct height at ends for large equipment with overcurrent devices?
• What is the sequence for energizing equipment after installation under Article 110?
• What is the typical minimum height for the working space around general electrical equipment?
• Cables and conductors installed exposed on the surfaces of ceiling 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.
• After modification affecting fault current, the maximum available fault current shall be verified or recalculated as necessary to ensure what?
• 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.
• Working space distances for enclosed live parts shall be measures from the __________ of equipment or apparatus if the live parts are enclosed.
• General requirements for 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 which article?
• How should access to energized parts be controlled?
• The form of the available fault current value when provided by electric utilities is?
• Conductor terminal and splicing devices shall be ________ for the conductor material and that shall be properly installed and used.
• What does general safety requirements in Article 110 encompass?
• What are the typical minimum working space dimensions around general electrical equipment as stated in Article 110.26?
• 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.
• How should equipment be protected against physical damage in exposed locations?
• Rainproof enclosure types are typically associated with which enclosure group?
• If the equipment enclosure width is greater than 30 inches, the minimum required width of the front-space is:
• Which statement most accurately describes how equipment should be located to ensure accessibility and safety?
• What is a core requirement for panelboards and switchboards in Article 110?
• Why is it important that installation instructions include clearance requirements?
• How should the working space be considered when multiple pieces of equipment share space?
• The working clearance space for outdoor installations shall include the zone described in ______.
• The area above the dedicated space may be used to accommodate foreign systems.
• What does Article 110 direct about placement to ensure safe working space?
• Which term describes equipment that has been evaluated against standards and bears a listing or labeling confirming compliance?
• What are the minimum dimensions for the front working space around panelboards?
• 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.
• Which term describes wiring methods included in the Code?
• 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.
• Which statement is true about the interrupting rating requirement for equipment?
• In spaces with limited access, the width of the working space shall be the width of the equipment enclosure or a minimum of how many inches, whichever greater?
• Tightening torque values for terminal connections shall be as indicated on equipment or in installed instructions provided by the manufacturer. An approved means shall be used to ____________ the indicated torque value.
• Which of the following equipment is explicitly named as capable of requiring arc-flash labeling when energized?
• What should be done if a modification conflicts with the equipment’s listing?
• Working space shall not be used for storage.
• Tightening torque values for terminal connections shall be as indicated on equipment or in installed instructions provided by the manufacturer. An approved means shall be used to achieve the __________ torque value.
• Wiring shall be installed so that the completed system will be free from
• True or False: Unused openings in electrical equipment must be closed to provide protection substantially equivalent to the wall.
• Field markings must have what property to withstand the environment involved?
• Each disconnecting means shall be legibly marked to indicate its purpose unless located and arranged so __________.
• In a laboratory rack scenario, which Article 110 considerations apply to safety?
• Some cleaning and lubricating compounds can cause severe deterioration of many plastic materials used for insulating and structural applications in equipment.
• What is a key safety objective regarding access to equipment?
• How does Article 110 address equipment installed in damp or wet locations?
• Listed or labeled equipment shall be installed and used in accordance with any instructions included in the listing or labeling.
• What is a labeling requirement for panelboards and switchboards?
• Product testing, evaluation, and listing (product certification) shall be performed by
• If equipment is relocated to a different room, what must be verified under Article 110?
• Reconditioned equipment's original listing mark may include the mark of the certifying body and not the entire equipment label.
• Unused openings in electrical equipment shall be ________.
• The term 'rainproof' is typically used with enclosure types _____.
• The manufacturer's name, trademark, or other descriptive marking by which the organization responsible for the product can be identified shall be where?
• Which statement describes proper anchoring of electrical equipment to structural members to ensure stability?
• What is the requirement for illumination in rooms with electrical equipment?
• How does Article 110 treat temporary wiring installations?
• Illumination shall be provided for all working spaces about service equipment, switchboards, switchgear, panelboards, or motor control centers _____.
• What equipment located at locations other than dwelling units must be legibly field marked with the available fault current, and include the date the calculation was performed?
• What should be considered for outdoor installations regarding weather exposure?
• Which statement about panelboard information is most accurate?
• If equipment is relocated, what condition should be checked regarding labeling and environment?
• Depth requirements apply to the front of equipment located in limited-access spaces.
• Enclosures intended for personal entry are within the scope of which article?
• How should equipment be anchored to reduce vibration and movement?
• The maximum extension from the front of the equipment allowed for the working space is how many inches?
• The minimum working space for access to live parts of equipment operating at 750 volts-to-ground with exposed live parts on one side and grounded parts on the other is how many feet?
• Only wiring methods recognized as ______ are included in this Code.
• Conductor sizes are expressed in American Wire Gauge (AWG) or
• Where electrical conductor material is not specified, the material and sizes given in the NEC shall apply to
• In a 4-wire delta-connected system where the midpoint of one phase winding is grounded, which conductor shall be durable and permanently marked by an orange outer finish?
• Which of the following describes the purpose of installation instructions provided by the manufacturer?
• Which maintenance approach is NOT part of staying compliant?
• NFPA 70E provides guidance such as determining the severity, planning safe work practices, arc-flash labeling, and selecting what?
• What documentation should accompany equipment to ensure compliance with Article 110?
• Service equipment labeling shall not be required if an arc flash label is applied in accordance with which industry practice?
• Field marking requirements for maximum fault current in non-dwelling installations are:
• NFPA 70E provides specific criteria for developing arc-flash labels for equipment that provides what?
• 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.
• How should wiring methods near electrical equipment be managed?
• Are temporary installations allowed under Article 110, and what conditions apply?
• If a disconnecting means is required to be locked in the open position by the NEC, the disconnect shall be capable of being locked in the open or closed position.
• Can equipment be used if it is not installed per its listing?
• The minimum height at each end of the working space is 6 1/2 ft.
• How should concealed wiring be treated under Article 110?
• Field marking of maximum available fault current at a service is not required in industrial installations where maintenance and supervision ensure that only qualified persons service the equipment.
• The action required after modification to ensure proper ratings includes?
• Listed or labeled equipment shall be installed and used in accordance with any instructions included in the listing or labeling.
• Two conditions must electrical equipment satisfy before installation under Article 110.
• What is the impact of ensuring proper listing and labeling on ongoing equipment safety?
• Which of the following is NOT a listed minimum working-space value?
• Which standard provides guidance for arc-flash labeling, safe work practices, and PPE?
• How should circuits be identified within a panel per Article 110?
• What does Article 110 say about accessibility of space around equipment?
• Which of the following is an example of equipment in non-dwelling units that may require arc-flash labeling when energized?
• Why must equipment be kept free of physical damage per Article 110?
• As applied to electrical equipment, the term 'reconditioned' may be interchangeable with the term(s) 'rebuilt, refurbished, or remanufactured' (any of these).
• Access and _______________ shall be provided and maintained about all electrical equipment to permit ready and safe operation and maintenance of such equipment.
• For equipment operating at 1,000 V nominal or less to ground and likely to require maintenance while energized, when located in space with limited access and above a lay-in ceiling, the opening shall be at least what size?
• Concrete, brick, or tile walls are considered which for working space requirements?
• Installation instructions may include environmental conditions. Which statement best describes the purpose of this information?
• The minimum distance above the enclosure for dedicated equipment space in indoor installations is 6 ft.
• Outdoor installations shall be ______.
• Which surfaces are considered grounded for working space requirements?
• The zone described in 110.26(A) pertains to the working clearance space for outdoor installations.
• What maintenance practices are expected for equipment?
• If equipment is relocated or repurposed, what must be verified?
• Which of the following statements about warning labels is true?
• All enclosure doors or hinged panels shall be capable of opening to a minimum of how many degrees?
• Where caution, warning, or danger signs or labels are required by this Code, the labels shall warn of the hazards using effective _____________.
• NFPA 70E provides guidance on safe work practices such as establishing an electrically safe work condition, arc-flash labeling, and selecting PPE. Which element is included in this guidance?
• For 300 volts-to-ground with exposed live parts on both sides of the workspace, the required working space is?
• What is the title of NFPA 70E?
• Which of the following describes the field marking for series-rated installations?
• General requirements for examination and approval, installation and use, access to and spaces about electrical conductors and equipment; enclosures intended for personal entry; and tunnel installations are within the scope of which article?
• 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.
• Connectors and terminals for conductors more finely stranded than Class B and Class C, shall be _________ for the specific conductor class or classes.
• What information should the panelboard directory contain?
• Fiber optic cables installed exposed to __________, or other contaminants may result in an undetermined alteration of optical fiber cable properties.
• How should electrical equipment be arranged with respect to other building systems?
• How should maintenance be performed to stay in compliance?
• How does Article 110 interact with more specific equipment articles like panelboards or motors?
• All splices, joints, and free ends of conductors shall be covered with an insulation equivalent to that of the conductors or with an identified insulating device.
• 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.
• The area above the dedicated space required by 110.26(E)(1)(a) may contain foreign systems if protection is installed to prevent damage to electrical equipment from condensation, leaks, or breaks.
• Which of the following is an approved means to verify that torque has been applied correctly?
• Which action helps ensure a connection to terminal parts does not damage the conductors?
• Equipment operating at 1,000V or less to ground that may require servicing while energized must have the space in front of the enclosure comply with depth requirements.
• Besides the available fault current, what else must be included on the field marking?
• Equipment interrupting 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.
• In judging equipment for approval, considerations such as
• How should warning signs and labels be applied near electrical equipment?
• 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.
• Reconditioned equipment shall be identified as 'reconditioned' and the original listing mark removed. Which option completes this statement?
• All switchboards, panelboards, and motor control centers shall be _____.
• How does Article 110 influence equipment placement within a room?
• What responsibilities do owners have regarding installation and maintenance?
• Who should access energized parts according to Article 110?
• Which activities qualify as servicing for arc-flash hazard marking for equipment such as switchboards and motor control centers?
• Which statement accurately describes the front-space width requirement when the equipment enclosure width is larger than 30 inches?