Independent Electrical Contractors (IEC) 212 Practice Exam

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• What is the minimum service disconnect rating for a two-wire branch circuit installation?
• In a 120/240-volt service, converting lighting loads from volt-amperes to amperes is performed by dividing by which voltage?
• For a one-family dwelling served with a 120/240-volt single-phase service, the service disconnect rating shall be not less than how many amperes?
• In a typical 3-conductor cable (hot-hot-neutral), which colors are used for hot conductors and which for neutral?
• A show window feeder load is measured in VA. True or False?
• Which NEC article covers the volt-ampere rating of multioutlet assemblies?
• Which table provides the demand factors for the general lighting load in dwelling units?
• Which statement correctly differentiates the equipment grounding conductor from a bonding jumper?
• Which calculation method is used for dwelling units that includes heating or A/C loads along with general loads?
• Refer to the nail salon safety switch scenario. The fuses provide which protection for the ungrounded service conductors between the switch and the utility transformer?
• NM-B cable is typically used for what type of wiring?
• Laundry receptacle outlets are included in the residential load calculations at a value of ___ volt-amperes per circuit.
• The NEC requires the ampacity of a feeder shall be equal to, or greater than ___.
• The minimum demand for an electric clothes dryer in a residential load calculation is ___ watts.
• If a branch circuit is rated at 6 amps, the minimum ampacity for the ungrounded service conductors should be at least which value?
• What is a 'box fill' calculation used for?
• Using the optional calculation method, four or more separately-controlled electric space-heating units are calculated at ___% of their nameplate ratings.
• Service-drop conductors shall have ___.
• Where permissible, the demand factor applied to that portion of the unbalanced neutral feeder load in excess of 200 amps is ___ percent.
• Which device provides overload protection for a motor?
• For an installation not more than two 2-wire branch circuits, the service disconnecting means rating shall not be less than how many amperes?
• For a residence with a 5 kW oven and a 7 kW cooktop, the minimum feeder demand factor (in kW) is closest to which value?
• Using the standard calculation, the demand load for household electric ranges rated in excess of ___ kW is computed per NEC Table 220.55.
• What is a motor starter and why is it used?
• The required sizing for service conductors is not less than what percentage of the continuous load plus 100 percent of the noncontinuous load?
• It shall be permissible to apply a demand factor of ___% to the nameplate ratings of 4 or more fastened-in-place water heaters in a multifamily dwelling.
• Branch-circuit calculations for the purpose of determining the size of a service or feeder are covered in which NEC article?
• The feeder ampacity must not be less than the service-entrance when the feeder's ampacity does not exceed how many amperes?
• What safety steps should be followed when performing work near energized equipment?
• How many 20-amp small-appliance branch circuits are required for a typical kitchen?
• What is the purpose of a panel's main disconnect?
• Which of the following statements best describes GFPE requirements in the configurations listed?
• If the service head cannot be located above the point of attachment, what is the maximum distance allowed from the point of attachment?
• In a multiwire branch circuit, what is the function of the neutral conductor?
• How many service(s) shall generally supply a building or structure?
• A feeder connects service equipment to which components?
• What is the purpose of a conduit body?
• GFPE device installation: Which configuration requires GFPE device?
• A feeder supplying a 5 kW wall-mounted oven and a 7 kW counter-mounted cooktop in a residence shall have a minimum demand factor of ___.
• Before working on a circuit, what practical test confirms de-energization?
• What does NEC Table 250.122 address?
• The NEC provides motor-size calculation guidelines in which article?
• In the billboard base pole service example, which statement best describes the minimum ampacity for ungrounded conductors?
• When sizing a service, the dryer’s VA may be a fixed value or the nameplate rating, whichever is greater. What fixed VA value is used?
• Which action is prohibited for service conductors supplying a single building?
• Each 480-volt, three-phase, wye-connected feeder disconnect with a minimum rating of ___ amperes is required to be ground-fault protected.
• Where required, drawings for feeder installations must be submitted before which point?
• Distinguish between a branch circuit and a feeder.
• The service disconnecting means shall not be located in which location?
• The minimum feeder-circuit conductor size, before adjustment factors, must have an ampacity equal to the noncontinuous load plus what percent of the continuous load?
• In dwelling units, what is the rule for receptacle spacing along walls?
• What is the primary purpose of lockout/tagout procedures?
• What is the standard residential voltage system in the United States?
• Loads such as heating and air conditioning that do not operate at the same time are noncoincident loads. When calculating service load only the ___ of two noncoincident loads needs to be included.
• Which of the following best describes the required height for service-drop conductor attachment above finish grade?
• What is the minimum feeder load in VA for a 40-foot-long show window?
• What is the minimum VA per sign circuit in service calculations?
• In a basic lockout/tagout procedure before servicing electrical equipment, which set of actions represents three essential steps?
• A practical consequence of using undersized conductors for a given load?
• When wiring outdoors, which methods or materials are typically used?
• Branch circuits and feeder conductors shall not be installed in the same ___ with service conductors. I. raceway II. cable III. enclosure
• The NEC allows ___ receptacle outlets to be connected on a 120-volt residential lighting or small-appliance branch circuit.
• The standard calculation's 75% factor applies to the load of which group?
• For 480-volt feeder disconnects, ground-fault protection is required for those with a minimum rating of what amperes?
• Service conductors must be sized to not less than 125 percent of the continuous load plus 100 percent of the noncontinuous load.
• Ground-fault protection is required for a feeder disconnect if which conditions apply?
• A 1,000-watt space heater on a 120-volt branch circuit—what is the approximate operating current?
• When installing a 240/120-V three-wire feeder underground from a dwelling unit to a detached garage on the same property, which requirement best describes Code obligations?
• For a manufacturing building, the service equipment disconnect shall be installed at a readily accessible location either outside or inside nearest the entrance of the service conductors. Which phrase correctly completes the requirement?
• If the panel spaces are all occupied, which panel configuration is indicated as a possible option for the shack feeder?
• In the 24-circuit service panel scenario, which of the following is the smallest main breaker size?
• Overhead conductors for festoon lighting shall be supported by messenger wire in spans exceeding how many feet?
• For a single-family dwelling with 3,500 square feet of occupied area, the minimum number of 15‑ampere lighting branch circuits is which amount?
• Dividing the lighting load in volt-amperes by 240 to obtain the lighting current is used in sizing which service configuration?
• A unit load for storage spaces in other than dwellings is at least ___ volt-amperes per square foot.
• Which factor is not considered when sizing conductors for ampacity?
• In the example, which conduit type is used for the underground feeder to the detached garage?
• Feeders containing a common neutral are permitted to supply which configurations?
• The fuses in a nail salon safety switch provide which protection for the ungrounded conductors between the switch and transformer?
• Which of the following is NOT listed as protection for service entrance cables subject to physical damage?
• GFPE device installation: which configuration requires GFPE device?
• The feeder conductor ampacity shall not be less than that of the service-entrance conductors where the feeder conductors carry the total load supplied by service-entrance conductors with an ampacity of ___ amperes or less.
• In an inductive load, what happens to current phase relative to voltage?
• If festoon lighting exceeds ___ feet, the conductors shall be supported by messenger wire.
• What is the purpose of an arc-flash boundary assessment?
• GFCI protection is required for receptacles in which locations?
• When should a dedicated circuit be considered for a large appliance?
• What maximum percentage voltage drop on feeders is recommended to provide reasonable efficiency of operation?
• Which table provides the dryer demand factors used in sizing the service?
• What is a primary safety benefit of keeping circuit labels clear and updated in a panel?
• In noncoincident loads calculation, which approach is used for two loads that do not operate simultaneously?
• In a 120/240-V system with only one hot conductor, what color is typically used for the hot conductor?
• What is the main function of a fuse or circuit breaker?
• For purposes of calculating a residential service, the general-purpose lighting load is calculated at ___ per square foot of area.
• Which factor is commonly considered in a box-fill calculation?
• What NEC article governs grounding and bonding?
• Live vegetation, such as trees, may support overhead conductor spans.
• What is the size of the smallest aluminum service-drop conductor allowed for installation?
• When calculating the service-entrance conductors for a farm service, the second-largest load of the total load, shall be computed at ___%.
• The NEC specifies that the maximum number of receptacles that can be connected to a 15-amp, 120-volt branch circuit in a school is ___.
• Feeder and service-entrance conductors with demand loads determined by 220.82 are permitted to have the ___ load determined by 220.61.
• The demand load for household ranges above 1.75 kW uses which NEC table?
• At 180 VA per outlet, how many outlets can be installed on a 20-ampere circuit (120 volt) if the circuit loading is to remain within its ratings?
• Which statement about arc-flash boundary assessment is true?
• What is the difference between a resistive load and an inductive load in terms of current phase?
• The service entrance cables shall be supported within not more than which distance of every service head, gooseneck, or connection to a raceway or enclosure?
• What percent demand factor applies to the portion of the unbalanced neutral feeder load in excess of 200 amps when allowed?
• In sizing feeders, why is voltage drop considered?
• Which NEC article covers general wiring methods and materials?
• For a feeder supplying household cooking equipment and electric clothes dryers, the maximum unbalanced load on the neutral conductor shall be considered as ___ of the load on the ungrounded conductors.
• Which statement best describes the use of Table 220.54 in NEC calculations?
• Name a common cause of overheating in electrical panels.
• The smallest main breaker that can be installed in a 24-circuit service panel on a commercial building is ___ amps.
• The small-appliance and laundry loads ___ be permitted to be included with the general lighting load and subjected to the demand factors provided in NEC Table 220.42.
• What is the typical recommended approach to labeling circuits in a panel?
• Overhead festoon lighting spans require messenger wire for spans exceeding how many feet?
• For a 120/240-volt, 1Ø, 3-wire service, the minimum clearance at the area accessible to automobiles but not trucks is 12.
• Overhead conductors shall not be installed beneath openings through which materials may be moved. Which option correctly describes their position relative to the openings?
• What is the purpose of a grounding electrode system?
• The point of attachment height for service-drop conductors above finish grade is at least which height?
• Reasonable efficiency of operation for the feeder can be achieved when which factor is considered in sizing the feeder conductors?
• Which factor is used in NEC guidelines to size equipment grounding conductors?
• Overhead service conductors shall have a minimum clearance from final grade of 24 1/2 feet when installed over tracks of what?
• How far must service entrance cables be supported from every service head, gooseneck, or connection to a raceway or enclosure?
• Where buildings exceed 3 stories or 50 feet in height, overhead lines must leave a clear space of at least ___ feet wide to facilitate ladder raising.
• Where feeders share a common neutral and are installed in a metal raceway, the conductors must be enclosed within what?
• Under the standard calculation, four or more appliances which are fastened-in-place in a one-family dwelling are computed at ___% of the total load for all appliances.
• Why is continuing education important for IEC 212 exam preparation?
• The minimum number of 120-volt, 15-amp lighting branch circuits required for a dwelling that has 70 × 30 ft. of livable space is ___.
• For a one-family dwelling with a 3-wire service, the minimum service disconnect rating is which value?
• An overhead feeder is installed to a residential garage. The conductors have a voltage of 120 volts to ground and do not pass over a sidewalk or driveway. What is the minimum height above the ground that must be maintained?
• Laundry receptacle outlets are included in residential load calculations at 1,500 volt-amperes per circuit. Which unit expresses this value?
• Which statement best describes a dedicated circuit?
• GFPE device installation: which installation requires GFPE device?
• The minimum underground service-lateral copper and aluminum sizes are 8 AWG copper and 6 AWG aluminum.
• What is the primary function of AFCI protection in residential branch circuits?
• When a conduit containing service entrance conductors runs beneath a building, what is the minimum depth of concrete required to cover a conduit for it to be considered outside the building?
• The described 120/208-volt feeder is a four-wire feeder. Which statement is true about the feeder type?
• Service conductors shall have a clearance not less than how many feet from windows, doors, or similar locations that open?
• What color is typically used for an equipment grounding conductor?
• GFCI protection is required for receptacles in which locations?
• What is the purpose of a service disconnect?
• The minimum size underground service-lateral conductor shall not be smaller than ___ AWG copper or ___ AWG aluminum.
• Which statement about bonding jumpers is correct?
• When using the optional calculation method for dwelling units, this method considers heating or A/C loads and ___ loads.
• What factors are included in a box-fill calculation?
• In the described 120/208-volt, 3-phase, 4-wire feeder setup, which statement is true about the feeder?
• For the calculations required in Article 220, the total area of an occupancy is determined from the ___ dimensions of the building or structure.
• What is the purpose of a panel schedule?
• Which NEC article should be consulted for motor-load sizing considerations?
• When sizing conductors for ampacity, which factors must be considered?
• A service on the base support pole of a single-sided billboard has a branch circuit loaded to 6 amps. The minimum ampacity for the ungrounded service conductors is ___ amps.
• Which of the following is a direct outcome of performing an arc-flash boundary assessment?
• What is the main purpose of a voltage regulator in a building electrical system?
• Which term best completes the sentence: Overhead branch circuit and feeder conductors shall not be installed ______ openings through which materials may be moved?
• Which statement best describes the safety role of the equipment grounding conductor?
• Which statement is true about a grounding electrode system?
• Which statement accurately describes GFCI protection for bathroom receptacles?
• The point of attachment of the service-drop conductors to a building must not be less than ___ feet above finish grade.
• A feeder to a detached structure must include which conductor for safety?
• When a calculation results in a fraction of an ampere of ___ or more, the NEC® permits "rounding up" to the next ampere.
• When documenting a circuit on a panel schedule, what information is typically included?
• Loads computed for dwelling unit ___ circuits shall not be included with the general lighting load.
• In this Park-and-Fly setup, the shack requires how many separate circuits for receptacles, lighting, and the window unit?
• When sizing a service, the dryer’s VA may be a fixed value or the nameplate rating; if the fixed value is used, what fixed VA value is used?
• Service entrance cables, where subject to physical damage, shall be protected by any of the following ___. I. EMT II. IMC III. RMC
• Which NEC article covers conductors and box fill?
• Which statement about the described feeder installation to a detached garage is true?
• In a purely resistive circuit, how does current relate to voltage?
• For a 277/480-volt, 3Ø, 4-wire service, the minimum clearance above the roof is not 3.
• When sizing the service, the dryer demand factors are given in which NEC table?
• What is a common use for a busbar in a distribution panel?
• Overhead branch circuit and feeder conductors shall not be installed in which location with respect to openings through which materials may be moved?
• What is the primary reason for proper tool insulation?
• Which type of electrical fault is AFCI designed to detect primarily?
• The minimum number of 15-amp, 120-volt, lighting circuits required for a 12,000 sq. ft. multifamily dwelling is ___.
• What describes the difference between 3-phase and single-phase power?
• A unit load of not less than ___ volt-amperes per square foot shall be included for storage spaces in other than dwellings.
• Service conductors must be sized for not less than ___ percent of the continuous load plus 100 percent of the noncontinuous load.
• When calculating loads to determine the size of a 120/240-volt 1Ø, 3-wire service, the lighting load in amps is calculated by ___ the lighting load in volt-amps by 240 volts.
• The feeder in the example is powered from a circuit breaker of what rating?
• Which of the following wiring methods is permitted by the NEC® for the service-entrance conductors for residences?
• Where a service mast is used for the support of service drop conductors, it shall be of adequate strength or be supported by ___.”
• For a one-family dwelling, the service disconnecting means shall have a rating not less than ___ amperes, 3-wire.
• What PPE is appropriate for arc-flash tasks?
• The load for a required sign branch circuit shall be computed at a minimum of ___.
• How should conductors be secured to protect from mechanical damage?
• For a dwelling with a 120/240-volt, single-phase service, what is the minimum service disconnect rating?
• Before servicing electrical equipment, which action is essential to ensure worker safety?
• What is the purpose of the neutral conductor in a 120/240-V system?
• For the shack stub-up, which device is permitted as a stub-up point for the conduit?
• What maximum total voltage drop on feeders is typically recommended to ensure reasonable efficiency of operation?
• Box fill calculations take into account which items?
• In a standard 3-conductor cable, which color is the neutral conductor?
• Which main breaker size is the smallest for a 24-circuit service panel according to the material?
• Are loads computed for dwelling unit small-appliance circuits permitted to be included with the general lighting load and subjected to Table 220.42 demand factors?
• The NEC 220.43(B) rule relates to calculating the load for which kind of installation?
• Signs shall be calculated at a minimum of how many volt-amperes per required sign circuit?
• If a service mast is used for the support of service drop conductors, it shall be of adequate strength or be supported by braces or guy wires.
• NEC Table 250.122 uses overcurrent device rating to size which component?
• Conductors on poles shall be separated by at least ___ inches where not placed on racks or brackets.
• How does a ground-fault circuit interrupter differ from a standard circuit breaker?
• The general-purpose lighting load per square foot is 3 VA. For a building of 2,000 square feet, the general lighting load is how many VA?
• What is the minimum clearance from windows, doors, or other openings for service conductors?