NEC 2020 Code Questions Practice Test 8

Question 1: what size of conductor must be used to protect against over current for a continuous load of 22 amperes at 75⁰C?

• 10 THWN
• 12 THWN
• 16 THWN
• 8 THWN

NEC Reference: NEC 210.19(A)(1)

Question 2: What size of feeder conductors are required for a dwelling unit which has a calculated load of 240 A. The service disconnect is rated for 250 A and feeder conductors carry entire load of the dwelling unit?

• 1/0 AWG
• 2/0 AWG
• 3/0 AWG
• 4/0 AWG

NEC Reference: NEC 310.12

Question 3: What size branch circuit conductor is required for a 4000 W, 240 electric water heater?

• 12 AWG
• 14 AWG
• 8 AWG
• 10 AWG

NEC Reference: NEC 422.10(A)

Question 4: How many number of 500 kcmil THWN conductors that can be installed in a 4 in. * 4 in. wireway?

• 4 conductors
• 5 conductors
• 6 conductors
• 7 conductors

NEC Reference: NEC 376.22(A)

Question 5: If a service is fed by three parallel sets of 400 kcmil conductors, what is the required conductor size for GEC?

• 3/0 AWG
• 2/0 AWG
• 2 AWG
• 4 AWG

NEC Reference: NEC 250.166

Question 6: Which of the following is the size of single supply-side bonding jumper is required for three metal raceways, each containing 300 kcmil service conductors?

• 2 AWG
• 3 AWG
• 1/0 AWG
• 1 AWG

NEC Reference: NEC 250.102(C)(1)

Question 7: If the length doesn’t exceed ………. Feet the cord and plug connections are allowed for swimming pool pump motors?

• 3 feet
• 5 feet
• 10 feet
• 8 feet

Question 8: After the demand factor is applied , what is the general lighting load of a hospital which is having 80,000 sq ft area?

• 42,000 VA
• 1,60,000 VA
• 58,000 VA
• 82, 000 VA

NEC Reference: NEC 220.12

Question 9: A 115/230 delta configured three phase transformer is rated at 45 KVA. What is its high-leg voltage of the transformer secondary?

• 230 volts
• 399 volts
• 199 volts
• 208 volts

Question 10: What is the maximum size over current device is required for a 4200 W, 240 V electric water heater connected in a building.

• 25 A
• 30 A
• 35 A
• 40 A

NEC Reference: NEC 422.11(E)

Question 11: Receptacles installed in a dwelling unit crawl space at or below grade level require:

• GFCI protection
• AFCI protection only
• No protection is required
• A metal cover plate only

NEC Reference: NEC 210.8(A)(4)

Question 12: Service conductors must be arranged at the service head to form a drip loop, so that:

• Water does not enter the raceway or equipment
• The conductors are shortened for cost savings
• The neutral can be omitted
• It has no safety purpose

NEC Reference: NEC 230.54(F)

Question 13: Under the 25-foot tap rule, tap conductors not over 25 feet in length must have an ampacity of at least what fraction of the rating of the overcurrent device from which the tap conductors are supplied?

• One-tenth
• One-third
• One-half
• Full rating (100%)

NEC Reference: NEC 240.21(B)(2)

Question 14: The main bonding jumper at service equipment must be sized based on which table, using the largest ungrounded service-entrance conductor?

• NEC Table 250.66
• NEC Table 220.12
• NEC Table 310.16
• No table is used, it is always 6 AWG

NEC Reference: NEC 250.28(D)

Question 15: At service equipment, normally non-current-carrying metal parts likely to become energized must be effectively bonded together, including which of the following?

• Service raceways and equipment enclosures
• Only the customer's furniture
• Nothing needs to be bonded at service equipment
• Only decorative trim

NEC Reference: NEC 250.92(A)

Question 16: Conductors in vertical raceways must be supported if the vertical rise exceeds the value in NEC Table 300.19(A). For 250 kcmil aluminum conductors, this maximum support interval is:

• Determined from NEC Table 300.19(A) by conductor size
• No support is ever required in vertical raceways
• Always exactly 100 feet regardless of size
• Always exactly 6 feet regardless of size

NEC Reference: NEC 300.19(A)

Question 17: In walls or ceilings of combustible material, outlet boxes must be installed so the front edge is set back from the finished surface by no more than:

• 1/4 inch
• 1/2 inch
• 1 inch
• 2 inches

NEC Reference: NEC 314.20

Question 18: The ampacity of Type AC cable conductors must be determined according to which sections, similar to the rule for NM cable?

• NEC 310.14 and 310.15
• It is not permitted to be determined at all
• It is always 15 amperes regardless of size
• The manufacturer decides with no code basis

NEC Reference: NEC 320.80

Question 19: Intermediate metal conduit (IMC) is permitted for use under all atmospheric conditions and occupancies, similar to which other wiring method, subject to specific corrosion protection requirements?

• Rigid metal conduit (RMC)
• Flexible cord
• NM cable
• It has no comparable wiring method

NEC Reference: NEC 342.10

Question 20: Flush-type snap switches installed in outlet boxes that are set back from a finished surface of concrete, tile, or other noncombustible material must be installed so that:

• The mounting yoke is held rigidly at the surface
• The switch may float freely inside the wall
• No support requirement applies
• Only tape is used to secure it

NEC Reference: NEC 404.10

Question 21: 15 and 20 ampere, 125 and 250 volt nonlocking receptacles installed outdoors in a damp or wet location must be listed as:

• Weather-resistant (WR) type
• Standard indoor-grade receptacles
• No specific listing is required
• Isolated-ground type

NEC Reference: NEC 406.9(C)

Question 22: A luminaire (other than a paddle fan) supported by an outlet box must not exceed the box's support rating, and outlet boxes used for this purpose must:

• Be designed or listed to support the weight
• Never need to support any weight
• Be made only of PVC
• Have no fill limit at all

NEC Reference: NEC 410.30(A)

Question 23: A counter-mounted cooking unit or wall-mounted oven is permitted to be cord-and-plug connected using a flexible cord within what length range?

• 18 to 36 inches
• 6 to 12 inches
• 48 to 72 inches
• Any length

NEC Reference: NEC 422.16(B)(2)

Question 24: Fixed electric space-heating equipment and associated motors are considered a continuous load; branch-circuit conductors and overcurrent devices for such equipment must be sized at not less than what percentage of the total load?

• 100 %
• 115 %
• 125 %
• 150 %

NEC Reference: NEC 424.3(B)

Question 25: Motor control circuit conductors not extending beyond the equipment enclosure require overcurrent protection sized according to which table?

• NEC Table 430.72(B)
• NEC Table 220.12
• NEC Table 250.66
• No table applies to control circuits

NEC Reference: NEC 430.72

Question 26: For multimotor and combination-load air-conditioning or refrigeration equipment, the maximum branch-circuit short-circuit and ground-fault protection is generally limited to what percentage of the rated-load or FLA of the largest motor, plus the sum of the other loads?

• 175 %
• 225 %
• 300 %
• 400 %

NEC Reference: NEC 440.22(B)

Question 27: Where a generator is installed to operate as a standby power source, and it is not visible from the transfer switch, the system must include which indicating feature?

• An indicator light or similar means at the transfer equipment
• No indication is required
• A telephone call to the utility
• A padlock only

NEC Reference: NEC 445.16

Question 28: A transformer nameplate must give the name of the manufacturer, rated kVA, frequency, primary and secondary voltage, and:

• Impedance (for larger transformers)
• The installer's home address
• No nameplate data is required
• The customer's account number

NEC Reference: NEC 450.11

Question 29: A single continuous-duty motor has a full-load current of 12 amperes. What is the minimum required ampacity of the branch-circuit conductors?

• 12 amperes
• 15 amperes
• 18 amperes
• 24 amperes

NEC Reference: NEC 430.22(A)

Question 30: Per NEC Article 100, the "main bonding jumper" is the connection at the service that joins the grounded circuit conductor to which of the following?

• The equipment grounding conductor at the service
• A telephone ground wire
• Nothing — it has no defined purpose
• The gas piping only

NEC Reference: NEC Article 100