NEC 2020 Code Questions Practice Test 5

Question 1: What is the minimum size of aluminium conductor used for surge protective devices?

• 12 AWG
• 14 AWG
• 10 AWG
• 8 AWG

NEC Reference: NEC 242.62

Question 2: Which of the following is the standard fuse rating of an electrical fuse as per NEC?

• 45
• 50
• 55
• 60

Question 3: Without applying any de-rating factor for conductor current carrying capacity, how many conductors can run parallel in raceway or cable?

• 4
• 3
• 5
• 6

NEC Reference: NEC 310.15(B)(3)(a)

Question 4: A 120 volts panel has a rating of 50A. What is its maximum over current device rating?

• 50 A
• 62.5 A
• 57.5 A
• 75 A

Question 5: Which of the following is maximum operating voltage of a low voltage lighting system?

• 30 volts
• 25 volts
• 40 volts
• 35 volts

NEC Reference: NEC 411.2

Question 6: The standby power shall be available not more than ……………..

• 30 seconds
• 75 seconds
• 1 minute
• 2 minute

NEC Reference: NEC 701.11

Question 7: In class I division 2 location, unless it is specified the cross sectional area of the conductors permitted in a seal shall not exceed …………. percentage of a cross sectional area of RMC

• 25
• 30
• 40
• 50

NEC Reference: NEC 501.15(C)(6)

Question 8: Branch circuits for heating and air conditioning equipment located in the elevators shall not exceed which of the following voltage?

• 600 volts
• 480 volts
• 240 volts
• 900 volts

NEC Reference: NEC 620.3(C)

Question 9: What is the minimum volume allowance required per a No 14 AWG conductor?

• 1.50 in³
• 1.75 in³
• 2.0 in³
• 2.5 in³

NEC Reference: NEC 314.16(B)

Question 10: Mutli-wire branch circuits shall not be permitted in class I division I locations.

• True
• False

NEC Reference: NEC 501.40

Question 11: A 125 volt, 15 or 20 ampere receptacle must be located within what distance of HVAC equipment for servicing purposes?

• 10 feet
• 25 feet
• 50 feet
• 100 feet

NEC Reference: NEC 210.63

Question 12: For installations consisting of not more than two 2-wire branch circuits, the service disconnecting means must have a rating of not less than:

• 15 amperes
• 30 amperes
• 60 amperes
• 100 amperes

NEC Reference: NEC 230.79(B)

Question 13: Where the ampacity of a conductor does not correspond with a standard overcurrent device rating, and the conductor is not part of a multi-outlet branch circuit supplying receptacles, the next higher standard rating is permitted only if it does not exceed:

• 400 amperes
• 800 amperes
• 1200 amperes
• There is no limit

NEC Reference: NEC 240.4(B)

Question 14: The purpose of the effective ground-fault current path is to provide a low-impedance path facilitating the operation of the overcurrent device or ground-fault detector during a:

• Ground fault on the wiring system
• Normal, everyday operation
• Voltage drop conditions only
• Lightning strikes only

NEC Reference: NEC 250.4(A)(5)

Question 15: An isolated ground receptacle is used to reduce which of the following at sensitive electronic equipment?

• Electrical noise / electromagnetic interference
• Voltage
• Ampacity
• Water intrusion

NEC Reference: NEC 250.146(D)

Question 16: Direct-buried conductors or cables may be spliced or tapped underground without a splice box, provided the splice method is:

• Listed for direct burial
• Wrapped with ordinary electrical tape
• Splices are never allowed underground
• Soldered only, with no other method allowed

NEC Reference: NEC 300.5(E)

Question 17: Per NEC Table 314.16(A), a 4 inch round or octagonal box that is 1 1/2 inch deep has a listed volume of:

• 12.5 cubic inches
• 15.5 cubic inches
• 18 cubic inches
• 21 cubic inches

NEC Reference: NEC Table 314.16(A)

Question 18: Even though the conductors inside NM cable may have a 90 C insulation rating, the ampacity of NM cable must be determined using which temperature rating column?

• 60 C
• 75 C
• 90 C
• 105 C

NEC Reference: NEC 334.80

Question 19: Liquidtight flexible metal conduit (LFMC) is commonly used to connect which type of equipment where flexibility and moisture resistance are both needed?

• Motors and vibrating equipment
• Overhead service drops only
• Underground burial only, with no conduit
• It has no permitted uses

NEC Reference: NEC 350.10

Question 20: Flexible cords and cables are permitted to be used for which of the following?

• Connection of portable lamps and appliances
• As permanent fixed building wiring
• Run through a wall cavity permanently
• As a substitute for a raceway in new construction

NEC Reference: NEC 400.10

Question 21: Where a switch handle is operated vertically, the "up" position of the handle must correspond to which switch state?

• On (closed)
• Off (open)
• It has no meaning
• Tripped/fault position

NEC Reference: NEC 240.81

Question 22: A receptacle installed in a damp location (such as under a roofed, open porch protected from direct rain) must be provided with an enclosure that is:

• Weatherproof when the receptacle is covered
• No cover is required in a damp location
• Explosion-proof
• Fireproof only

NEC Reference: NEC 406.9(A)

Question 23: Cord-and-plug-connected vending machines manufactured after a certain date must include which factory-installed protection within the attachment cord or plug?

• GFCI protection
• AFCI protection
• No protection is required
• Surge protection only

NEC Reference: NEC 422.51

Question 24: A motor disconnecting means (other than for a torque motor) must have an ampere rating of not less than what percentage of the motor full-load current?

• 100 %
• 115 %
• 125 %
• 150 %

NEC Reference: NEC 430.110(A)

Question 25: For hermetic refrigerant motor-compressors, ampacity and overcurrent protective device sizing must be based on which current value from the equipment nameplate?

• The nameplate rated-load current
• The horsepower table value only
• A fixed value of 20 amperes always
• The service panel rating

NEC Reference: NEC 440.6(A)

Question 26: Conductors from the generator terminals to the first distribution device containing overcurrent protection must have an ampacity of not less than what percentage of the nameplate current rating for a generator that is not a continuous-load application?

• 100 %
• 115 %
• 125 %
• 150 %

NEC Reference: NEC 445.13

Question 27: At carnivals, circuses, and fairs, ground-fault circuit-interrupter protection for personnel is required for:

• 125 volt, 15 and 20 ampere receptacles
• Only 480 volt equipment
• No GFCI protection is required at carnivals
• Only lighting circuits

NEC Reference: NEC 525.23

Question 28: Each electric sign and outline lighting system must be provided with an externally operable switch or circuit breaker disconnecting means, located:

• Within sight, or lockable in the open position
• Anywhere in the building
• No disconnect is ever required
• Only at the utility transformer

NEC Reference: NEC 600.6

Question 29: For an installation consisting of a single 2-wire branch circuit, the service disconnecting means must have a rating of not less than:

• 15 amperes
• 30 amperes
• 60 amperes
• 100 amperes

NEC Reference: NEC 230.79(A)

Question 30: The ampacity of conductors supplying an individual AC arc welder is determined by multiplying the rated primary current by a multiplier based on the:

• Welder duty cycle
• Ambient humidity
• Building square footage
• Number of welders on site

NEC Reference: NEC 630.11(A)