Definitions

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1. 1 · Definitions · NEC Knowledge

   A heater draws its full 16 A for 2 hours and 40 minutes every time it runs, then cycles off. A coworker calls it a continuous load and wants the 125% factor on that basis. Using the Article 100 idea of a continuous load, is the label earned?

   1. A. Yes. Any load that runs more than one hour is continuous.
   2. B. No. A continuous load is one expected to run at maximum current for 3 hours or longer.Keyed answer
   3. C. Yes. The off time is ignored, so every cycling heater is continuous.
   4. D. No. Only motors can be continuous loads.

   Article 100 describes a continuous load as one where the maximum current is expected to continue for 3 hours or more. Two hours and forty minutes does not meet that definition, so the continuous-load factor is not earned on that basis. Confirm the definition in NEC 2026, then the sizing rules in Articles 210 and 215.

   Open NEC 2026 Article 100

2. 2 · Definitions · NEC Knowledge

   You multiply the connected load by a number smaller than 1 so the feeder is sized for what you expect at one time, not for every load added together. What is that number called?

   1. A. Demand factorKeyed answer
   2. B. Ampacity
   3. C. Interrupting rating
   4. D. Continuous load

   A demand factor is the ratio of the demand you expect to the total connected load. Ampacity is how much current a conductor may carry. Interrupting rating is the fault current a device can open. Continuous load describes duration. The definition is in Article 100. The tables that apply the factors are in Article 120.

   Open NEC 2026 Article 100

3. 3 · Definitions · NEC Knowledge

   Which conductor is intentionally connected to ground at the service and normally carries current back from the load while the load is running?

   1. A. Equipment grounding conductor
   2. B. Grounding electrode conductor
   3. C. Bonding jumper
   4. D. Grounded conductorKeyed answer

   The grounded conductor is the normal return, often called the neutral on an AC system. The equipment grounding conductor carries current when something faults. The grounding electrode conductor ties the system to the electrode. A bonding jumper connects metal parts. Article 100 defines the terms. Article 250 tells you where each one lands.

   Open NEC 2026 Article 100

4. 4 · Definitions · NEC Knowledge

   One disconnect is behind a locked door that the worker can open with a key, with no ladder. A second disconnect is 9 ft up and needs a ladder. Using the Article 100 idea that readily accessible means reachable quickly without climbing, which disconnect is readily accessible?

   1. A. Only the one that needs a ladder.
   2. B. Neither, because both disconnects are indoors.
   3. C. Both, because both are in the same building.
   4. D. The one behind the keyed door.Keyed answer

   Readily accessible rules out a climb or a portable ladder. A key is not the same obstacle as a ladder. The 9 ft disconnect fails that idea, and the keyed door does not. Confirm the definition in NEC 2026 Article 100 before you apply a service or motor rule that uses the term.

   Open NEC 2026 Article 100

5. 5 · Definitions · NEC Knowledge

   A room has a basin and a toilet and no tub or shower. A coworker says it is not a bathroom, so the receptacle beside the basin can skip the bathroom rules. What does the definition used by those rules say?

   1. A. A bathroom needs a tub or a shower. A basin and a toilet are exempt.
   2. B. Any room with a toilet is a kitchen if it also has a light.
   3. C. A bathroom includes a room with a basin and at least one of a toilet, urinal, tub, or shower. This room meets that idea.Keyed answer
   4. D. Bathroom rules apply only when the room is over 50 square feet.

   Article 100 defines a bathroom by a basin plus one of those plumbing fixtures. A toilet counts. The receptacle rules in Article 210 use that definition, so skipping them because there is no tub is the mistake. Confirm the definition in NEC 2026.

   Open NEC 2026 Article 100

6. 6 · Definitions · NEC Knowledge

   A transformer inside a building has no direct connection between its primary supply conductors and its secondary conductors, other than grounding and bonding. What is the secondary system called?

   1. A. A Class I, Division 1 location.
   2. B. A service lateral.
   3. C. A multiwire branch circuit.
   4. D. A separately derived system.Keyed answer

   A separately derived system is supplied by a source that has no direct connection to another system's supply conductors, other than grounding and bonding connections. A transformer used that way is the usual case. The term is in Article 100. Bonding it is Article 250.

   Open NEC 2026 Article 100

7. 7 · Definitions · NEC Knowledge

   An ungrounded conductor touches a metal box, and current flows on the equipment grounding path. Which Article 100 term names that event?

   1. A. A ground fault.Keyed answer
   2. B. An overload that only warms a conductor slowly, with no contact to metal.
   3. C. A service point.
   4. D. A demand factor.

   A ground fault is an unintentional connection between an ungrounded conductor and ground or normally grounded metal. An overload is too much load current without that contact. Confirm the term in NEC 2026 Article 100. The path that carries the fault is Article 250.

   Open NEC 2026 Article 100

8. 8 · Definitions · NEC Knowledge

   A study card says overcurrent is current above the rating of equipment or the ampacity of a conductor, and that the word covers three kinds of events. Which set matches that idea?

   1. A. Service drop, service lateral, and service point.
   2. B. Overload, short circuit, and ground fault.Keyed answer
   3. C. Box fill, raceway fill, and conductor support.
   4. D. Voltage drop, demand factor, and power factor.

   Overcurrent covers overload, short circuit, and ground fault. They are not the same event, and Articles 240 and 430 protect them in different ways. The definition that ties the three words together is in Article 100. Confirm it in NEC 2026.

   Open NEC 2026 Article 100

9. 9 · Definitions · NEC Knowledge

   A room in a dwelling has a sink and built-in equipment for preparing and cooking food. Which Article 100 term is the one that turns on the small-appliance circuit rules?

   1. A. Bedroom.
   2. B. Bathroom.
   3. C. Hallway.
   4. D. Kitchen.Keyed answer

   The kitchen entry in Article 100 is what tells you the small-appliance and countertop rules of Article 210 apply. Confirm the wording in NEC 2026 Article 100, then use Article 210 for the circuits. A bathroom and a hallway are different defined areas.

   Open NEC 2026 Article 100

10. 10 · Definitions · NEC Knowledge

    Which of these is a raceway, using the Article 100 idea of an enclosed channel made to hold wires, rather than a cable or a cord?

    1. A. A cord supplying a table lamp.
    2. B. Nonmetallic-sheathed cable.
    3. C. Electrical metallic tubing.Keyed answer
    4. D. A grounding electrode conductor lying on a footing.

    EMT is a raceway, and its article is 358. Nonmetallic-sheathed cable is a cable assembly under Article 334, not a raceway. A lamp cord is Article 400. Confirm the raceway definition in NEC 2026 Article 100.

    Open NEC 2026 Article 100

11. 11 · Definitions · NEC Knowledge

    A load draws current in pulses, so the neutral of a 3-phase, 4-wire circuit can carry more than the simple unbalance of a linear load. Which Article 100 term names that load?

    1. A. Demand factor.
    2. B. Service lateral.
    3. C. Continuous load.
    4. D. Nonlinear load.Keyed answer

    A nonlinear load is one whose current waveform does not follow the voltage waveform. Harmonic current can add on the neutral. The term is in Article 100. When you count current-carrying conductors, confirm the neutral rule in NEC 2026 Article 310.

    Open NEC 2026 Article 100

12. 12 · Definitions · NEC Knowledge

    At the garage subpanel the helper lands the equipment grounding conductor on the neutral bar and tells the apprentice the green and white wires are the same conductor once they touch. He wants that landing copied at the next panel. What is the right ruling?

    1. A. Once the green wire touches the neutral bar, the two wires become one grounded conductor and the bond is finished.
    2. B. The green wire is the grounded conductor, so it belongs on the neutral bar in every panel.
    3. C. The white wire is the grounded conductor, the normal return. The green wire is the equipment grounding conductor, the fault path. Joining them in the subpanel is not the bonding point for this system.Keyed answer
    4. D. Bonding means the fault path and the normal return share a bar in each enclosure.

    Article 100 separates the grounded conductor, the equipment grounding conductor, and bonding. The return carries normal current. The equipment grounding conductor carries fault current. They are joined only where the system is bonded, not at this subpanel. Confirm the definitions in NEC 2026 and the subpanel rule in Article 250.

    Open NEC 2026 Article 100

13. 13 · Definitions · NEC Knowledge

    The only shutoff for this rooftop unit is inside a locked electrical room, and the person who has to open it does not have the key. The helper says a lock is fine because the building engineer can bring a key later. Is that shutoff readily accessible?

    1. A. No. A locked door is a locked obstacle. Ready access does not wait on someone else's key.Keyed answer
    2. B. Yes. A lock improves access because it keeps the handle available for the engineer.
    3. C. Yes, if the door is metal, because metal doors are treated as readily accessible covers.
    4. D. No, because ready access exists only outdoors at the meter.

    Article 100 makes readily accessible a practical test: no ladder, no tool, and no locked obstacle for the person who must operate the equipment. A key the operator does not have fails that test. Confirm the definition in NEC 2026.

    Open NEC 2026 Article 100

14. 14 · Definitions · NEC Knowledge

    Showroom track lighting is on for two hours each evening and then switched off. The helper applies the continuous-load multiplier because the lights are on a schedule and he treats every scheduled load as continuous. What duration did he skip?

    1. A. Any load on a daily schedule is continuous, and two hours is enough.
    2. B. Continuous means the luminaires are fastened in place, so the hours do not matter.
    3. C. Continuous means the load is expected to run for three hours or more. Two hours is not a continuous load, so the multiplier does not belong on it.Keyed answer
    4. D. A load under three hours is sized at twice its current.

    Article 100 sets continuous load by duration: three hours or more. A two-hour showroom schedule is outside that definition, and the continuous multiplier does not apply. Confirm the definition in NEC 2026.

    Open NEC 2026 Article 100

15. 15 · Definitions · Calculations

    This drill defines demand load as connected load times the demand factor. Lighting connected load is 25,000 VA with a demand factor of 0.40. Fixed electric heat of 8,000 VA is taken at 100% in the same total, because this drill does not reduce heat. What is the combined demand load?

    1. A. 10,000 VA
    2. B. 13,200 VA
    3. C. 18,000 VAKeyed answer
    4. D. 33,000 VA

    Lighting demand is 25,000 × 0.40 = 10,000 VA. Heat stays at 8,000 VA. The combined demand is 18,000 VA. Applying 0.40 to both loads gives 13,200 VA. Adding the connected totals with no factor gives 33,000 VA. Article 100 names demand factor. Article 120 is where a problem tells you which loads are reduced.

    Open NEC 2026 Article 100

16. 16 · Definitions · Calculations

    A conductor's table ampacity is 40 A. The problem gives an ambient correction factor of 0.88 and a current-carrying-conductor adjustment of 0.80. Both factors apply. What ampacity may you use, to the nearest tenth of an ampere?

    1. A. 28.2 AKeyed answer
    2. B. 32 A
    3. C. 35.2 A
    4. D. 40 A

    40 × 0.88 = 35.2 A after ambient correction. Then 35.2 × 0.80 = 28.16 A, which is 28.2 A to the nearest tenth. Using only the conductor-count factor on 40 A gives 32 A. Stopping after ambient leaves 35.2 A. Article 310 is where both factors come from. They are printed in the stem.

    Open NEC 2026 Article 310

17. 17 · Definitions · Calculations

    This problem defines power factor as real power divided by apparent power. Real power is 4,800 W. Apparent power is 6,000 VA. What is the power factor?

    1. A. 1.25
    2. B. 0.90
    3. C. 0.60
    4. D. 0.80Keyed answer

    4,800 / 6,000 = 0.80. Dividing the other way gives 1.25, which does not fit the definition in the stem. Power factor is electrical math. When that current sizes a transformer conductor, Article 450 is the next article.

    Open NEC 2026 Article 100

18. 18 · Definitions · Calculations

    A nonlinear load is on a 3-phase, 4-wire circuit. The problem gives the neutral current as 22 A and the largest phase current as 16 A. How many amperes above the largest phase current is the neutral?

    1. A. 16 A
    2. B. 6 AKeyed answer
    3. C. 4 A
    4. D. 38 A

    22 − 16 = 6 A. The neutral is carrying more than the largest phase, which is the behavior the nonlinear-load term is warning you about. Article 100 defines the load. Article 310 tells you when that neutral counts as current-carrying.

    Open NEC 2026 Article 100

19. 19 · Definitions · Calculations

    The problem says the grounded conductor of this single-phase multiwire circuit carries only the unbalanced current, defined as the difference between the two ungrounded legs. One leg is 18 A and the other is 7 A. What current does the grounded conductor carry?

    1. A. 25 A
    2. B. 11 AKeyed answer
    3. C. 18 A
    4. D. 7 A

    18 − 7 = 11 A. Adding the legs gives 25 A, which is not the unbalanced current this stem defined. The grounded conductor is the normal return. Confirm the term in Article 100, and identify that conductor under Article 200.

    Open NEC 2026 Article 100

20. 20 · Definitions · Calculations

    Corridor lighting is 24,000 VA connected with a demand factor of 0.5. A sign on the same feeder is 6,000 VA and, for the feeder conductor load in this drill, is taken at 125% because it is continuous. The lighting demand is not multiplied by 125% again. What is the combined feeder load?

    1. A. 18,000 VA
    2. B. 19,500 VAKeyed answer
    3. C. 24,375 VA
    4. D. 12,000 VA

    Lighting demand is 24,000 × 0.5 = 12,000 VA. The sign is 6,000 × 1.25 = 7,500 VA. Combined, 19,500 VA. Adding the sign at 100% skips the continuous factor. Taking 125% of the lighting demand as well double-counts a load that was already demanded. Article 120 builds the lighting demand. Article 215 is the conductor factor.

    Open NEC 2026 Article 120