National Electrical Code (NEC) Codes and Standards Practice Exam

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• AC and DC conductors rated 1,000 V or less may occupy the same space provided that all conductors have what property?
• The term described by a voltage rating such as 240V or 480V indicates what about the circuit breaker?
• For the installation of boxes and enclosures in electrical systems, which article is primary?
• Where fuses are used as the service overcurrent device, the disconnecting means shall be located ahead of the load side of the fuses in accordance with 230.91.
• AFCI protection typically protects which type of location?
• True or False: A receptacle on a dwelling unit small-appliance branch circuit may be used to supply an electric clock.
• GFCI protects against, and which article covers it?
• The distance for GFCI protection near sinks and bathtubs is measured as the shortest path.
• Underground service-entrance conductors shall be protected against physical damage.
• Which NEC article covers hazardous (classified) locations?
• When IMC is cut in the field, reaming is required to remove burrs and rough edges.
• Feeder and service loads for fixed electric space-heating loads shall be calculated at _____ percent of the total connected load.
• For a separate building or structure supplied by a separately derived system, the supply conductors shall contain an equipment grounding conductor.
• In industrial laboratories, receptacles within 6 ft of a sink that supply equipment where removal of power would create a greater hazard are exempt from GFCI protection if they are which ratings?
• Which NEC article focuses on Overcurrent protection: sizing and protecting conductors and devices to prevent overheating?
• Which article provides guidance for NM cable installation?
• Exothermic or irreversible compression connections, together with the mechanical means used to attach to fireproofed structural metal, shall not be required to be accessible.
• Wiring methods and cabling systems listed for use in plenums shall be permitted to be installed in ducts specifically fabricated for environmental air-handling purposes if which conditions are met?
• GFCI protection is designed to protect against what?
• Additional requirements for installing receptacles in dwelling unit countertops and work surfaces can be found in Article _____ .
• Under what conditions may the disconnecting means for a feeder-supplied building be located elsewhere on the premises?
• Which NEC article governs the use and identification of conductors, including color coding and identification rules?
• Exterior raceways shall be drained and shall be listed and labeled for use in wet locations. Which term describes the approval status required for exterior raceways used in wet locations?
• Where the supplemental electrode is a rod, that portion of the bonding jumper that is the sole connection to the supplemental grounding electrode shall not be required to be larger than _____ AWG copper wire.
• Which statement about load calculations and feeders is true?
• The white conductor within a cable may be permanently reidentified to indicate its use as an ungrounded conductor at each visible location. This statement is:
• Which statement is true regarding service conductors and building openings?
• When bare conductors are installed with insulated conductors, their ampacities shall be limited to which option?
• An 800A fuse rated at 1,000V _____ be used on a 250V system.
• For GFCI protection for personnel, the distance from receptacles near sinks and bathtubs is measured as the _____ path the cord would follow without piercing a floor, wall, ceiling, fixed barrier, or passing through a door, doorway, or window.
• The minimum grounded conductor size for paralleled service-entrance conductors is not smaller than 1/0 AWG.
• _____ conductors shall not be used for more than one branch circuit, one multiwire branch circuit, or more than one set of ungrounded feeder conductors except as allowed elsewhere in the Code.
• Overhead service conductors or service equipment can be supported to hardwood trees.
• Which article provides guidance for the installation of armored cable?
• Which sub-articles provide details for specific hazards within hazardous locations?
• Article 230 focuses on which area of electrical systems?
• The continuity of a grounded conductor shall not depend on a connection to _____.
• An equipment grounding conductor shall be identified by any of several acceptable methods. Which option best represents this requirement?
• Direct-buried conductors subject to frost movement shall be arranged to prevent damage to the enclosed conductors or to equipment connected to the raceways. Which option best matches this requirement?
• The requirement for maintaining a 3-foot vertical clearance from the edge of the roof shall not apply to the final feeder conductor span where conductors are attached to _____.
• What is the role of NEC inspections in ensuring safety?
• Which protective feature is specified for outdoor installations where required?
• The point of attachment of overhead premises wiring to a building shall in no case be less than _____ ft above finished grade.
• Which NEC article is specifically dedicated to optical fiber cables?
• Raceways on exteriors of buildings or other structures shall be arranged to drain and shall be _____ for use in wet locations.
• The minimum vertical clearance for overhead feeder conductors not exceeding 1,000V passing over commercial areas subject to truck traffic is _____ ft.
• Which of the following best describes elements that count toward box-fill calculations?
• Exposed structural metal interconnected to form a metal building frame that is not intentionally grounded or bonded and is likely to become energized, shall be bonded to the _____.
• Which article focuses on services: service conductors and service equipment, including service disconnects?
• Overcurrent protection shall not exceed which rating for 10 AWG copper conductors?
• Which NEC article covers emergency systems?
• Which article focuses on conductors for general use: ampacity, insulation, and temperature ratings?
• Which NEC article covers legally required standby systems?
• Show-window lighting minimum feeder load is 200 VA per linear foot.
• The minimum feeder load for show-window lighting is _____ VA per linear foot.
• Conductors are considered outside a building when they are installed ______.
• What does Article 200 cover?
• A laundry receptacle outlet shall not be required in each dwelling unit of a multifamily building, if laundry facilities are provided on the premises for all building occupants.
• All 15A and 20A, 125V, single-phase receptacles installed in dwelling unit boathouses shall have GFCI protection.
• Which NEC article is commonly referenced for air-conditioning and refrigeration equipment design?
• A circuit breaker with a _____ voltage rating, such as 240V or 480V, can be used where the nominal voltage between any two conductors does not exceed the circuit breaker voltage rating.
• Where service-entrance conductors are installed in parallel in two or more raceways or cables, the size of the grounded conductor in each raceway or cable shall be based on the total circular mil area of the parallel ungrounded service-entrance conductors in the raceway or cable, sized in accordance with 250.24(C)(1), but not smaller than _____ AWG.
• Insulated conductors used in wet locations shall be which of the following?
• An equipment grounding conductor shall be identified by _____ .
• Which article covers luminaires and lighting equipment?
• Which NEC article covers photovoltaic (PV) systems?
• What does NEC 406.12 require in dwelling units?
• In NEC terminology, what is a service?
• Which article contains the additional requirements for receptacle outlets in dwelling unit countertops and work surfaces?
• An insulated grounded conductor of _____ AWG or smaller shall be identified by a continuous white or gray outer finish, or by three continuous white or gray stripes along its entire length on other than green insulation.
• Grounded conductors of 6 AWG or smaller shall be identified by what marking method?
• Where documented safe switching procedures are established and maintained and the installation is monitored by _____ individuals, the disconnecting means for a building supplied by a feeder can be located elsewhere on the premises.
• Service conductors shall not be installed beneath openings through which materials may be moved and shall not be installed where they will obstruct entrance to these buildings' openings.
• Receptacles installed for countertop and similar work surfaces as specified in 210.52(C) shall not be considered as the receptacle outlets required by 210.52(A).
• Reaming is required when IMC is cut in the field to remove burrs and rough edges.
• What is the NEC requirement for kitchen countertop receptacles?
• For 10 AWG copper conductors, the permissible overcurrent protective device rating is 30A.
• When bare conductors are installed with insulated conductors, their ampacities shall be limited to which of the following?
• Overcurrent devices shall not be located which of the following places?
• Threadless couplings approved for use with IMC in wet locations shall be which of the following?
• Sectioned equipment grounding conductors smaller than which AWG size shall be permitted in multiconductor cables if the combined circular mil area of the sectioned equipment grounding conductors in each cable complies with 250.122?
• Why are permits and inspections important for electrical work?
• For underground service conductors supplying power to limited loads of a single branch circuit, the minimum copper size is:
• Which of the following statements is true regarding bonding of lightning protection ground terminals?
• The service disconnecting means rated 1,000V or less shall be marked to identify it as being suitable for use as service equipment and shall be _____.
• Insulated conductors used in wet locations shall be which of the following?
• For general-use conductors' ampacity, insulation, and temperature ratings, which article applies?
• Which article covers appliances and appliance circuits?
• Why is voltage rating important for conductors and insulation?
• The white conductor within a cable can be used for a(n) _____ conductor where permanently reidentified to indicate its use as an ungrounded conductor at each location where the conductor is visible and accessible.
• What is the function of an equipment grounding conductor (EGC)?
• In industrial laboratories, receptacles within 6 ft of a sink that supply equipment where removal of power would create a greater hazard are not required to have GFCI protection if they meet which rating criteria?
• Independent support wires in nonfire-rated assemblies must be distinguishable from which type of wires?
• In NEC terminology, what is a branch circuit?
• Additional services for a single building or structure may be permitted if permitted by _____.
• Where a branch circuit supplies continuous loads, or any combination of continuous and noncontinuous loads, the rating of the overcurrent device shall not be less than the noncontinuous load plus 125 percent of the continuous load.
• Grounded conductors _____ AWG or larger can be identified by distinctive white or gray markings at their terminations.
• Which NEC article covers communications systems?
• What type of enclosure is required for electrical equipment installed in an air-handling space?
• What is the maximum rod-type grounding electrode diameter for which listing is required?
• When sizing a feeder for the fixed appliance loads in dwelling units, a demand factor of 75 percent of the total nameplate ratings can be applied if there are _____ or more appliances fastened in place on the same feeder.
• Which statement best describes the rationale for requiring working space around electrical equipment?
• Which NEC article governs temporary wiring on construction sites?
• A circuit breaker having an interrupting current rating of other than _____ shall have its interrupting rating marked on the circuit breaker.
• In NEC terminology, what is a feeder?
• Plenum wiring is permitted in ducts fabricated for environmental air-handling purposes if the total length of such wiring does not exceed how many feet?
• The portion of the bonding jumper that connects to a rod-type supplemental grounding electrode shall not be larger than 6 AWG copper.
• What is the purpose of using demand factors in load calculations?
• What is the minimum height above finished grade for the point of attachment of overhead wiring to a building?
• For 14 AWG copper conductors, the permissible overcurrent protective device rating is 15A.
• Neutral conductors shall not be used for more than one branch circuit, one multiwire branch circuit, or more than one set of ungrounded feeder conductors except as allowed elsewhere in the Code. This statement is:
• Which article focuses on general wiring methods and the installation of conductors, cables, raceways, and enclosures?
• When IMC enters a box, fitting, or enclosure, what is required to protect the wire from abrasion?
• Which scenario illustrates voltage rating compatibility as shown by the example of an 800A fuse rated at 1,000V used on a 250V system?
• Which NEC article focuses on Grounding and bonding to establish a safe path to earth and equalize potential?
• Receptacles installed in a dwelling unit kitchen to serve countertop surfaces shall be supplied by not fewer than _____ small-appliance branch circuits.
• The statement that exposed structural metal in the area served by a separately derived system must be bonded to the grounded conductor of each system is true.
• What is the purpose of box-fill calculations?
• Which factors determine conductor ampacity?
• How should outdoor electrical installations be protected?
• Which NEC article covers general safety requirements for electrical installations, including enclosure integrity and workmanship?
• The following statement is true: Grounding electrode conductors that are 6 AWG or larger and not exposed to physical damage may be run along the surface of the building without metal covering.
• Cables laid in wood notches require protection against nails or screws by using a steel plate at least how thick?
• Typical rule for breaker sizing relative to conductor ampacity?
• Which statement is true about the NEC definition of a service?
• Which term describes conductors that carry power from the service equipment to distribution equipment or subpanels?
• What is the purpose of load calculations (Article 220)?
• Which statement about conductor adjustment factors is true?
• Which article focuses on boxes, enclosures, and fittings used in electrical installations?
• AFCI protection detects which fault type?
• Electrical equipment with low smoke and heat release properties, and wiring material suitable for the ambient temperature can be installed within an air-handling space if the enclosure is what?
• What happens to conductor ampacity when ambient temperature increases beyond the rating?
• Which of the following appliances installed in residential occupancies need not be connected to an equipment grounding conductor?
• Which NEC article covers motors and motor circuits?
• Conductor adjustment factors shall not apply to conductors in raceways having a length not exceeding how many inches?
• Which NEC article covers electrical signs and outline lighting?
• What is the primary purpose of the NEC?
• For raceway installations, conductors 8 AWG and larger must be stranded unless otherwise permitted or required in the NEC.
• Where IMC enters a box, fitting, or other enclosure, what shall be provided to protect the wire from abrasion unless the design affords equivalent protection?
• A receptacle connected to one of the dwelling unit small appliance branch circuits can be used to supply an electric clock.
• For a separate building or structure supplied by a separately derived system when overcurrent protection is provided where the conductors originate, the supply conductors shall contain a(n) _____.
• Supplementary overcurrent protection may be used to protect internal circuits of equipment. Which of the following best describes this application?
• Which NEC article covers motors and motor circuits?
• Grounding electrode conductors 6 AWG and larger that are not exposed to physical damage can be run along the surface of the building construction without metal covering or protection.
• GFCI protection is required for boathouse receptacles, specifically for which of the following scenarios?
• Direct-buried conductors subject to movement by settlement or frost shall be arranged to prevent damage to what?
• A device comprising _____ or more receptacles shall be calculated at not less than 90 VA per receptacle.
• Article 200 provides the requirements for _____.
• Which statement describes the purpose of weatherproof enclosures in outdoor electrical work?
• In a fire-rated floor-ceiling cavity, wiring shall not be supported by which items?
• A(n) _____ shall be used to connect the grounding terminal of a grounding-type receptacle to a grounded box.
• Electrical wiring within the cavity of a fire-rated floor-ceiling or roof-ceiling assembly shall not be supported by the ceiling assembly or ceiling support wires.
• What is the minimum thickness of a steel plate used to protect cables laid in wood notches?
• Which NEC article covers legally required standby systems?
• AFCI protection is designed to protect against which type of fault, and which article covers it?
• Supplementary overcurrent protection _____.
• Which article focuses on Nonmetallic-sheathed cable (NM)?
• It shall be permissible to ground meter enclosures immediately adjacent to the service disconnecting means to the _____ circuit conductor on the load side of the service disconnect, if service ground-fault protection is not provided.
• Which NEC article covers optical fiber cables?
• What is the difference between a fuse and a circuit breaker?
• Where independent support wires of a suspended ceiling assembly are used to support raceways, cable assemblies, or boxes above a ceiling, they shall be secured at how many ends?
• If exposed structural metal that is interconnected to form the building frame exists in the area served by the separately derived system, it shall be bonded to the grounded conductor of each separately derived system and each bonding jumper shall be sized in accordance with Table 250.102(C)(1) based on the largest ungrounded conductor of the service.
• Which NEC article covers health care facilities electrical systems?
• The receptacle outlet required for indoor electrical service equipment shall not be required to be installed for which type of dwelling?
• What is the difference between grounding and bonding?
• Which NEC article covers storage batteries?
• Which article covers flexible cords and cables?
• The receptacle outlet required for indoor electrical service equipment shall not be required to be installed for which dwelling type?
• Metal gas piping installed in or attached to a building shall be considered bonded when one or more grounding electrodes are used, if the grounding electrode conductor or bonding jumper to the grounding electrode is of sufficient size.
• Which NEC article covers transformers?
• What is the purpose of Article 110?
• In raceways, conductors of which size and larger must be stranded unless specifically permitted or required elsewhere in the NEC?
• Underground service conductors that supply power to limited loads of a single branch circuit shall not be smaller than _____.
• Ground clamps and fittings that are exposed to physical damage shall be enclosed in _____ or equivalent protective covering.
• Sectioned equipment grounding conductors smaller than 1/0 AWG are permitted in multiconductor cables if the combined circular mil area complies with a specified requirement. What is the size threshold?
• Conductor(s) other than service conductors shall not be installed in the same _____ in which the service conductors are installed.
• Underground service-entrance conductors are required to be protected against physical damage. Which statement best describes this requirement?
• Overhead service-entrance cables shall be equipped with which device?
• Lightning protection system ground terminals _____ be bonded to the building or structure grounding electrode system.
• Which article governs the installation of flexible cords and cables used in general electrical installations?
• If the use of multiple grounding connections results in objectionable current and the requirements of 250.4(A)(5) or (B)(4) are met, it shall be permitted to _____.
• Service raceways threaded into metal service equipment such as bosses (hubs) are considered to be effectively _____ to the service metal enclosure.
• An equipment bonding jumper can be installed on the outside of a raceway, providing the length of the equipment bonding jumper is not more than _____ in. and the equipment bonding jumper is routed with the raceway.
• Which NEC article covers emergency systems?
• For 12 AWG copper conductors, the permissible overcurrent protective device rating is 20A.
• What is the purpose of required working space around electrical equipment?
• Independent support wires used for the support of electrical raceways and cables within nonfire-rated assemblies shall be distinguishable from the suspended-ceiling framing support wires.
• Where it is unlikely that two or more noncoincident loads will be in use simultaneously, which load value is used in computing the total load to a feeder?
• Which NEC article covers air-conditioning and refrigeration equipment?
• What is the typical application location for GFCI protection?
• Which article focuses on Armored Cable (AC) usage and installation?
• If conductors are installed in parallel in the same raceway or cable tray, a single wire-type conductor shall be permitted as the equipment grounding conductor based on the overcurrent protective device for the _____.
• What does it mean for equipment to be listed and labeled?
• Which statement correctly describes the meaning of a straight voltage rating in circuit breakers?