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NEC Electrical Engineering practice questions

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Question 1General Electrical Requirements and Code Administration

The NEC is best described as which type of document?

  1. A federal statute enforced nationwide by a single agency
  2. A voluntary design guide with no legal standing anywhere
  3. A manufacturer installation manual for listed equipment
  4. A model code adopted by jurisdictions through legislation Correct answer.

Explanation

The NEC is a model code published by NFPA; it becomes enforceable only when a state or local jurisdiction adopts it into law, often with local amendments. It is not itself a federal statute, and enforcement varies by jurisdiction.

Question 2General Electrical Requirements and Code Administration

Which entity typically issues the permit and performs inspections for electrical work in a jurisdiction?

  1. The local authority having jurisdiction (AHJ) Correct answer.
  2. The electrical contractor's trade association
  3. The equipment listing laboratory
  4. The serving electric utility

Explanation

The AHJ is the organization or individual responsible for approving equipment, materials, and installations, and for enforcing the code. Permits and inspections are administered by that authority, commonly a municipal or county building department.

Question 3General Electrical Requirements and Code Administration

Under NEC Article 100 definitions, a branch circuit is defined as the circuit conductors between which two points?

  1. The meter socket and the main bonding jumper
  2. The utility transformer and the service disconnect
  3. The final overcurrent device protecting the circuit and the outlet(s) Correct answer.
  4. The panelboard bus and the grounding electrode

Explanation

A branch circuit runs from the final overcurrent protective device that protects the circuit to the outlets it serves. Conductors ahead of that device are feeders or service conductors, not branch-circuit conductors.

Question 4General Electrical Requirements and Code Administration

What is the primary purpose of the NEC as stated in Article 90?

  1. To guarantee that electrical systems will never fail
  2. To safeguard persons and property from electrical hazards Correct answer.
  3. To set electric rate structures for utilities
  4. To specify product manufacturing tolerances

Explanation

Article 90 states the purpose as the practical safeguarding of persons and property from hazards arising from the use of electricity. The code is not intended as a design specification or an instruction manual for untrained persons.

Question 5General Electrical Requirements and Code Administration

Which of the following installations is generally covered by the NEC?

  1. Premises wiring of a commercial building Correct answer.
  2. Wiring on railway rolling stock
  3. Aircraft electrical systems
  4. Automotive starting circuits

Explanation

Article 90 excludes installations in ships, railway rolling stock, aircraft, and automotive vehicles from the code's scope. Building premises wiring, including commercial occupancies, is covered.

Question 6General Electrical Requirements and Code Administration

What does the term 'listed' mean when applied to electrical equipment?

  1. The equipment is acceptable to the AHJ and has been evaluated by a qualified testing organization Correct answer.
  2. The equipment carries a minimum one-year warranty
  3. The equipment has been installed according to the manufacturer's instructions
  4. The equipment has been inspected on the job site by the installer

Explanation

Listed equipment is equipment included in a list published by a recognized testing organization that maintains periodic inspection and states the equipment meets designated standards. Listing is a product evaluation, separate from field installation.

Question 7General Electrical Requirements and Code Administration

Which of these is a recognized function of the AHJ when an installation is found to be noncompliant?

  1. Issuing a product listing for the equipment involved
  2. Rejecting the installation and requiring correction Correct answer.
  3. Requiring the utility to raise the service voltage
  4. Approving the installation as-is if it has worked before

Explanation

The AHJ has the authority to reject installations that do not comply with the adopted code and to require correction before approval. Approval is granted only when the work meets the code's minimum requirements.

Question 8General Electrical Requirements and Code Administration

A 120-volt branch circuit supplies a continuous load. What is the minimum branch-circuit rating permitted for a continuous load of 16 amperes, before any adjustment or correction factors are applied?

  1. 25 amperes
  2. 30 amperes
  3. 15 amperes
  4. 20 amperes Correct answer.

Explanation

Branch-circuit conductors and overcurrent devices for continuous loads must be sized at not less than 125 percent of the continuous load. 16 A × 1.25 = 20 A, so a 20-ampere circuit is the minimum standard size.

Question 9General Electrical Requirements and Code Administration

A feeder supplies a continuous load of 60 amperes and a noncontinuous load of 40 amperes. What is the minimum feeder overcurrent device rating, ignoring adjustment and correction factors?

  1. 110 amperes
  2. 100 amperes
  3. 115 amperes Correct answer.
  4. 125 amperes

Explanation

Feeder and service overcurrent devices are sized at not less than 125 percent of the continuous load plus 100 percent of the noncontinuous load. That gives 1.25 × 60 + 40 = 75 + 40 = 115 amperes.

Question 10General Electrical Requirements and Code Administration

When a branch circuit supplies an individual motor, how is the branch-circuit short-circuit and ground-fault protective device generally selected?

  1. At 250 percent of the motor full-load current for all motor types
  2. At 100 percent of the motor full-load current
  3. In accordance with the percentage allowances in the motor article, based on the motor type and protective device Correct answer.
  4. At 125 percent of the motor full-load current for all motor types

Explanation

Motor branch-circuit short-circuit and ground-fault protection is selected from the percentage allowances in Article 430, which differ by motor type, code letter, and whether the device is a fuse or breaker. There is no single percentage that applies universally.

Question 11General Electrical Requirements and Code Administration

What is the general rule for the ampacity of branch-circuit conductors supplying a continuous load, before any adjustment or correction factors?

  1. Not less than 125 percent of the load Correct answer.
  2. Not less than 100 percent of the load
  3. Not less than 150 percent of the load
  4. Not less than 200 percent of the load

Explanation

Branch-circuit conductors for continuous loads must have an ampacity of at least 125 percent of the load before applying adjustment or correction factors. The final ampacity after adjustment must still be sufficient for the load.

Question 12General Electrical Requirements and Code Administration

A 3-phase, 4-wire feeder serves balanced line-to-neutral loads. How many current-carrying conductors are counted for ampacity adjustment in the neutral?

  1. The neutral is not counted when it carries only the unbalanced current of the balanced portion Correct answer.
  2. The neutral is never counted as a current-carrying conductor
  3. The neutral is always counted as a current-carrying conductor
  4. The neutral is counted only when it carries more than the ungrounded conductors

Explanation

In a 3-phase, 4-wire circuit supplying only line-to-neutral loads, the neutral carries only the unbalanced current and is not counted as a current-carrying conductor. It is counted when it carries the total current of the circuit, such as with certain nonlinear loads.

Question 13General Electrical Requirements and Code Administration

What is the minimum working clearance in front of a 480-volt panelboard with exposed live parts on one side and no live parts on the other, where the nominal voltage to ground is 277 volts?

  1. 3.5 feet
  2. 3 feet Correct answer.
  3. 5 feet
  4. 4 feet

Explanation

For equipment operating at 151 to 600 volts to ground with exposed live parts on one side and no live parts on the other, the minimum working space is 3 feet. Greater depths are required when live parts are on both sides or the voltage is higher.

Question 14General Electrical Requirements and Code Administration

Which of the following describes the general requirement for the width of working space in front of electrical equipment?

  1. At least 36 inches or the width of the equipment, whichever is greater
  2. At least 48 inches or the width of the equipment, whichever is greater
  3. At least 24 inches or the width of the equipment, whichever is smaller
  4. At least 30 inches or the width of the equipment, whichever is greater Correct answer.

Explanation

The working space in front of electrical equipment must be at least 30 inches wide, or the width of the equipment, whichever is greater. The space must allow at least one full access path to the equipment.

Question 15General Electrical Requirements and Code Administration

What is the minimum headroom required for working space above a switchboard operating at 480 volts?

  1. 5 feet
  2. 8 feet
  3. 6 feet
  4. 6.5 feet Correct answer.

Explanation

The working space above electrical equipment must have a minimum headroom of 6.5 feet, except for certain installations where the equipment is 6.5 feet or less in height and the ceiling is at least 6 feet above the floor.

Question 16General Electrical Requirements and Code Administration

How is the ampacity of conductors sized when they are installed in a location where the ambient temperature exceeds the temperature rating basis of the conductor's ampacity table?

  1. By applying the ambient temperature correction factors from the appropriate table Correct answer.
  2. By relying on the overcurrent device to limit the load
  3. By derating the circuit to 50 percent regardless of temperature
  4. By increasing the conductor size by one standard trade size

Explanation

Conductors must be corrected for ambient temperature using the correction factor tables when the ambient differs from the table's basis. The corrected ampacity must still be adequate for the load.

Question 17General Electrical Requirements and Code Administration

A conduit contains 12 current-carrying conductors. Which statement best reflects how ampacity adjustment applies?

  1. No adjustment is required because the conduit is properly sized
  2. Adjustment is required only if the conductors are larger than 4/0 AWG
  3. Adjustment is required because the number of current-carrying conductors exceeds the threshold in the table Correct answer.
  4. Adjustment is required only if the ambient temperature exceeds 86 degrees F

Explanation

When more than three current-carrying conductors are installed together, ampacity must be adjusted using the applicable table based on conductor count. Twelve conductors falls well into a significant adjustment bracket.

Question 18General Electrical Requirements and Code Administration

What is the purpose of the equipment grounding conductor?

  1. To provide a low-impedance path for fault current to facilitate overcurrent device operation Correct answer.
  2. To carry the normal load current back to the source
  3. To balance the loads across the phases
  4. To reduce the voltage drop on long branch circuits

Explanation

The equipment grounding conductor bonds non-current-carrying metal parts to the grounding system, providing a low-impedance fault path so overcurrent devices operate quickly. It does not normally carry load current.

Question 19General Electrical Requirements and Code Administration

What is the primary function of the main bonding jumper in a service?

  1. To isolate the neutral from ground throughout the building
  2. To connect the grounding electrode to earth
  3. To connect the equipment grounding conductors to the service grounded conductor at the service equipment Correct answer.
  4. To provide overcurrent protection for the service conductors

Explanation

The main bonding jumper connects the equipment grounding conductor and the service grounded conductor at the service equipment, establishing the fault path. Grounding electrode conductors connect the system to earth, which is a separate function.

Question 20General Electrical Requirements and Code Administration

A building is supplied by a feeder from a service in another structure, and the feeder includes an equipment grounding conductor. What is the general requirement for the grounded conductor at the second building?

  1. It must be disconnected entirely at the second building
  2. It must be bonded to the equipment grounding conductor at the second building
  3. It must not be bonded to the equipment grounding conductor at the second building Correct answer.
  4. It must be connected to a grounding electrode at the second building and bonded to the equipment grounding conductor there

Explanation

For a feeder supplying a separate structure, the grounded conductor is not bonded to the equipment grounding conductor at the second building; the bonding occurs only at the service. This prevents parallel return paths through grounding conductors.

Question 21General Electrical Requirements and Code Administration

What is the general requirement for the identification of the grounded conductor in a panelboard?

  1. It must be identified with black finish
  2. It must be identified with green finish
  3. It must be identified with white or gray finish or other approved means Correct answer.
  4. It must be identified with red finish

Explanation

Grounded conductors must be identified by a white or gray finish or by other approved means, such as marking tape. Green is reserved for equipment grounding conductors, and black and red are typically ungrounded conductors.

Question 22General Electrical Requirements and Code Administration

What is the minimum size of the grounding electrode conductor for a service with 3/0 AWG copper service-entrance conductors, where the grounding electrode is a ground rod?

  1. 2 AWG copper
  2. 4 AWG copper
  3. 8 AWG copper
  4. 6 AWG copper Correct answer.

Explanation

For service conductors of 2 AWG through 1/0 AWG, the grounding electrode conductor must be at least 6 AWG copper. For 2/0 through 3/0 AWG, the minimum is 4 AWG copper.

Question 23General Electrical Requirements and Code Administration

What is the maximum permitted voltage drop for a branch circuit plus feeder combined, as recommended in the informational notes of the code?

  1. 10 percent
  2. 5 percent Correct answer.
  3. 3 percent
  4. 2 percent

Explanation

Informational notes recommend that the combined voltage drop of feeder and branch circuit not exceed 5 percent, with the branch circuit limited to 3 percent. These are recommendations, not mandatory requirements.

Question 24General Electrical Requirements and Code Administration

What is the minimum size of a copper equipment grounding conductor for a 20-ampere branch circuit?

  1. 14 AWG
  2. 12 AWG Correct answer.
  3. 10 AWG
  4. 8 AWG

Explanation

The equipment grounding conductor for a 20-ampere circuit must be at least 12 AWG copper, matching the minimum circuit conductor size. The table of minimum sizes ties the grounding conductor to the rating of the overcurrent device.

Question 25Wiring Methods and Materials

What is the minimum size copper conductor permitted for general branch-circuit wiring where the load does not exceed the ampacity of the conductor?

  1. 14 AWG Correct answer.
  2. 12 AWG
  3. 16 AWG
  4. 18 AWG

Explanation

The general minimum conductor size for branch circuits and feeders is 14 AWG copper, which corresponds to the smallest standard overcurrent protection rating of 15 A. Smaller conductors such as 16 AWG and 18 AWG are permitted only for limited applications like fixtures and control circuits.

Question 26Wiring Methods and Materials

A nonmetallic-sheathed cable is installed in a dwelling. Which characteristic must the cable assembly provide for the conductors inside?

  1. Mechanical protection and a flame-retardant outer covering Correct answer.
  2. Armor to resist physical damage from rodents
  3. Liquid-tight sealing for wet locations
  4. Continuous metallic shielding against radio interference

Explanation

NM cable consists of insulated conductors enclosed in an outer jacket that provides mechanical protection and flame retardance. It is not metallic-armored, not liquid-tight, and not intended for wet locations.

Question 27Wiring Methods and Materials

Which wiring method is required to be installed using fittings and connectors listed and identified for the specific use and location?

  1. Knob-and-tube wiring
  2. Open wiring on insulators
  3. Rigid metal conduit Correct answer.
  4. Fixture wire

Explanation

Raceway systems such as rigid metal conduit must use listed fittings and connectors suited to the conditions of use, including wet or corrosive locations. The other methods listed are either legacy systems or wiring within equipment, not raceway assemblies.

Question 28Wiring Methods and Materials

What is the primary purpose of supporting and securing a cable or raceway at intervals along its run?

  1. To provide an equipment grounding path
  2. To reduce voltage drop over long distances
  3. To increase the current-carrying capacity of the conductors
  4. To prevent strain on conductors and terminations and keep the wiring method in place Correct answer.

Explanation

Support and securing requirements keep the wiring method in position and prevent physical strain on conductors, splices, and terminations. Ampacity, grounding, and voltage drop are addressed by separate rules.

Question 29Wiring Methods and Materials

A junction box is installed in a ceiling. Which requirement applies to the box regarding accessibility?

  1. It may be buried in concrete if marked as such
  2. It must remain accessible without removing the building finish Correct answer.
  3. It may be covered by drywall if a wiring diagram is left
  4. It may be permanently concealed if splices are soldered

Explanation

Boxes containing splices or terminations must be accessible so that conductors and connections can be inspected and serviced. Concealing them behind finished surfaces is not permitted.

Question 30Wiring Methods and Materials

Which conductor material has a lower resistance per unit length, copper or aluminum, for the same cross-sectional area?

  1. Both are equal
  2. Silver has higher resistance than both
  3. Aluminum
  4. Copper Correct answer.

Explanation

Copper has lower resistivity than aluminum, so for the same cross-sectional area copper carries current with less resistance. This is why aluminum conductors often must be larger for a given ampacity.

Question 31Wiring Methods and Materials

Where a raceway is installed in a wet location, which characteristic must the raceway and its fittings have?

  1. They must be listed and identified as suitable for wet locations Correct answer.
  2. They must be painted to seal the joints
  3. They must be filled to 60 percent of capacity
  4. They must be installed only above grade

Explanation

Raceways and fittings used in wet locations must be listed and identified for wet locations so that water entry does not compromise the conductors. Painting, elevation, and fill percentages do not substitute for this listing.

Question 32Wiring Methods and Materials

A 20 A branch circuit supplies general-purpose receptacles. What is the minimum copper conductor size typically required?

  1. 12 AWG Correct answer.
  2. 16 AWG
  3. 14 AWG
  4. 10 AWG

Explanation

A 20 A circuit requires conductors with an ampacity of at least 20 A; 12 AWG copper is the standard minimum for this rating. 14 AWG is limited to 15 A circuits.

Question 33Wiring Methods and Materials

A conduit run contains four current-carrying conductors in a raceway where the ambient temperature is elevated. Which adjustment must be applied to conductor ampacity?

  1. Apply an ampacity correction factor for ambient temperature and an adjustment for conductor count Correct answer.
  2. Apply no adjustment because the conductors are insulated
  3. Apply only the standard overcurrent device rating
  4. Apply only a voltage-drop calculation

Explanation

Ampacity tables are based on specific conditions; elevated ambient temperature requires a correction factor, and more than three current-carrying conductors in a raceway require an adjustment factor. Both reduce the allowable ampacity.

Question 34Wiring Methods and Materials

A metal raceway is used as the equipment grounding conductor. Which condition must be met for this to be permitted?

  1. The raceway must be continuous, electrically continuous, and sized per the grounding rules Correct answer.
  2. The raceway must be painted on the inside
  3. The raceway must contain an insulated neutral
  4. The raceway must be filled to at least 40 percent

Explanation

A metal raceway may serve as the equipment grounding conductor only when it is continuous and electrically continuous and meets the sizing and installation requirements for grounding. Interior paint, fill, and a neutral conductor are unrelated.

Question 35Wiring Methods and Materials

A box contains six 12 AWG conductors, two cable clamps, and one device. Using the standard box-fill method based on conductor equivalents, what must the box volume accommodate?

  1. The equivalent volume of the conductors, clamps, and device counted per the fill table Correct answer.
  2. Only the volume of the device and clamps
  3. The volume of the largest conductor only
  4. Only the volume of the six conductors

Explanation

Box fill counts each conductor, each cable clamp, and each device or fitting using the equivalent volumes from the fill table, then compares the total to the box volume. Counting only conductors or only fittings understates the required volume.

Question 36Wiring Methods and Materials

A cable is fished through a finished wall without a box at a splice point. Which requirement applies to splices?

  1. Splices may be made in the wall if taped
  2. Splices are prohibited entirely
  3. Splices must be made in an accessible box or enclosure Correct answer.
  4. Splices may be made anywhere in the cable run

Explanation

Splices and joints must be enclosed in an accessible box or fitting so they can be inspected and serviced. Making splices loose in a wall or cable run is not permitted.

Question 37Wiring Methods and Materials

Which factor most directly determines the minimum burial depth of a rigid metal conduit installed underground?

  1. The location classification and whether the conduit is under a building or driveway Correct answer.
  2. The rating of the overcurrent device
  3. The number of conductors inside
  4. The color of the conduit

Explanation

Minimum cover requirements vary with the location, such as under a building, under a street or driveway, or in other soil conditions. Conduit color, conductor count, and overcurrent rating do not set burial depth.

Question 38Wiring Methods and Materials

An installer uses a metal-clad cable in a location subject to physical damage. Which consideration governs whether the cable is acceptable?

  1. Whether the cable contains more than three conductors
  2. Whether the cable is listed and identified for the conditions and protected where required Correct answer.
  3. Whether the cable jacket is a specific color
  4. Whether the cable is supported every 10 feet

Explanation

The wiring method must be listed and identified for the location and, where subject to physical damage, protected as required. Color, conductor count, and support spacing do not determine acceptability for a damage-prone location.

Question 39Wiring Methods and Materials

A raceway contains conductors of different sizes. Which rule applies to conductor fill?

  1. Fill is determined by the number of circuits only
  2. Only current-carrying conductors are counted
  3. The total cross-sectional area of all conductors must not exceed the permitted percentage of the raceway interior area Correct answer.
  4. Only the largest conductor is considered

Explanation

Raceway fill is based on the sum of the cross-sectional areas of all conductors compared to the permitted percentage of the raceway interior cross section. Considering only the largest conductor or only circuit count is incorrect.

Question 40Wiring Methods and Materials

Which of the following is a recognized method of protecting conductors where a cable passes through a bored hole in a wood stud that is close to the surface?

  1. Add a second cable in the same hole
  2. Wrap the cable in tape
  3. Increase the conductor size
  4. Install a listed protective plate or bushing at the penetration Correct answer.

Explanation

Where cables pass through framing members close to the surface, listed protective plates or bushings are used to prevent nails and screws from damaging the conductors. Tape, larger conductors, or additional cables do not provide this protection.

Question 41Wiring Methods and Materials

A feeder is installed in a location where the ambient temperature is higher than the base temperature used in the ampacity table. What is the correct approach?

  1. Reduce the conductor count in the raceway
  2. Select a corrected ampacity using the ambient temperature correction factor for the insulation type Correct answer.
  3. Use the table value unchanged
  4. Use the next larger overcurrent device

Explanation

Ampacity values must be corrected when the ambient temperature differs from the table's base conditions, using the correction factors for the conductor insulation. Using the uncorrected value can result in an overloading condition.

Question 42Wiring Methods and Materials

A junction box is installed in a damp location. Which feature is most important for the enclosure?

  1. It contains only copper conductors
  2. It is the largest box available
  3. It is listed for the location and provides drainage or a mounting position that prevents water accumulation Correct answer.
  4. It is painted a light color

Explanation

Enclosures in damp or wet locations must be listed for the location and installed so that water does not accumulate or enter. Size, color, and conductor material do not address moisture.

Question 43Wiring Methods and Materials

A conduit body is installed in a run of rigid metal conduit. Which requirement applies to the conduit body?

  1. It must be listed for the use and have sufficient volume for the conductors and splices Correct answer.
  2. It must be filled with a sealing compound
  3. It must be the same color as the conduit
  4. It must be installed only vertically

Explanation

Conduit bodies must be listed for the application and provide adequate volume for conductors and any splices, in accordance with the marking on the fitting. Sealing compound, color, and orientation are not general requirements.

Question 44Wiring Methods and Materials

A conductor with 90°C insulation is installed where the terminals are rated 75°C. How is the conductor ampacity determined for the termination?

  1. Limited by the 75°C terminal rating unless the equipment is listed otherwise Correct answer.
  2. Always based on the 90°C insulation rating
  3. Based on the lowest ambient temperature expected
  4. Based on the average of the two ratings

Explanation

The conductor ampacity at a termination is limited by the temperature rating of the terminals, even if the conductor insulation has a higher rating, unless the equipment is listed for a higher temperature. The insulation rating alone does not govern the termination.

Question 45Wiring Methods and Materials

A metal raceway system is installed with expansion fittings in a long straight run exposed to temperature changes. What is the main purpose of the expansion fittings?

  1. To allow additional conductors to be added later
  2. To increase the current-carrying capacity
  3. To accommodate length changes of the raceway without damaging the raceway or conductors Correct answer.
  4. To provide a grounding connection

Explanation

Expansion fittings allow the raceway to change length with temperature without inducing damaging stress on the raceway, fittings, or conductors. They do not affect ampacity, grounding, or future conductor additions.

Question 46Wiring Methods and Materials

A box is used to support a luminaire. Which condition must be satisfied for the box to support the luminaire?

  1. The box must contain at least three conductors
  2. The box must be listed and marked as suitable for the weight and support of the luminaire Correct answer.
  3. The box must be at least 4 inches square
  4. The box must be installed in a ceiling only

Explanation

A box used to support a luminaire must be listed and marked for that purpose and for the weight involved. Box dimensions, conductor count, and ceiling location alone do not establish support suitability.

Question 47Wiring Methods and Materials

A feeder tap is made from a larger feeder to a smaller conductor. Which consideration is most critical to the tap's compliance?

  1. The tap must be made with solder
  2. The tap conductor must be the same color as the feeder
  3. The tap conductor ampacity, length, and overcurrent protection must satisfy the tap rules for the application Correct answer.
  4. The tap must be installed in a vertical raceway

Explanation

Feeder tap rules limit the tap conductor size, length, and required overcurrent protection based on the specific application. Color, joining method, and raceway orientation are not the governing criteria.

Question 48Wiring Methods and Materials

A conductor is installed in a location where the ambient temperature is very low. Which property of the insulation is most relevant?

  1. The number of strands in the conductor
  2. The insulation's suitability for the low temperature and its flexibility at that temperature Correct answer.
  3. The color of the insulation
  4. The conductor's ampacity at high temperature

Explanation

At low temperatures, insulation can become brittle, so the insulation must be suitable for the low temperature and remain flexible. High-temperature ampacity, color, and stranding do not address cold-temperature performance.

Question 49Branch Circuits, Feeders, and Service Calculations

What is the maximum overcurrent protection rating generally permitted for a 14 AWG copper branch-circuit conductor?

  1. 20 A
  2. 25 A
  3. 15 A Correct answer.
  4. 30 A

Explanation

The ampacity of 14 AWG copper is 15 A under the standard 60°C column, and the general rule limits overcurrent protection to the conductor ampacity unless a specific exception applies.

Question 50Branch Circuits, Feeders, and Service Calculations

In a 120/240 V single-phase dwelling service, what is the minimum general lighting and receptacle load for a 2,000 sq ft dwelling before any demand factors?

  1. 6,000 VA
  2. 3,000 VA Correct answer.
  3. 4,000 VA
  4. 2,000 VA

Explanation

The general lighting and receptacle load is calculated at 3 VA per square foot for dwellings, so 2,000 sq ft × 3 VA = 6,000 VA before applying demand factors.