2024 Edition

Master Electrician - Test 3 - 2014 NEC


1. Given: After all demand factors have been taken into consideration for a commercial building, the balanced demand load is determined to be 75 kVA; the building has a 208Y/120-volt, 3-phase electrical system. What MINIMUM size copper conductors with THWN insulation are required for the ungrounded (phase) service-entrance conductors?
2. The NEC requires a MINIMUM of _____ receptacles to be provided in each operating room of a hospital.
3. In general, round access openings in a manhole shall NOT be less than _____ in diameter.
4. For other than dwelling units, all 125-volt, single-phase, 15- and 20-ampere receptacles located _____ shall be provided with GFCI protection for personnel.
5. In regard to a 7 hp, 480-volt, 3-phase ac motor with an 80 percent power factor and a full-load ampere rating of 19 amperes indicated on the nameplate, and a service factor of 1.15; when the initial setting of the overload device you have selected is not sufficient to carry the load, what is the MAXIMUM setting permitted for the overload protection?
6. Health care facilities require ground fault protection:
7. What MINIMUM voltage is required after 1 hours to serve emergency lighting from a storage battery, when the normal source voltage of 120 volts is interrupted?
8. Where the heating, air-conditioning or refrigeration equipment is installed on the roof of an apartment building, a 15- or 20-ampere, 125-volt receptacle _____.
9. Atmospheres containing combustible metal dusts such as aluminum
or magnesium are considered to be material _____ classifications.
10. Aluminum or steel cable trays shall be permitted to be used as equipment grounding conductors, provided _____ .
I. the cable tray sections and fittings are identified as an equipment grounding conductor
II. the cable tray sections and fittings are durably marked to show the cross-sectional area of the metal
11. What is the MINIMUM number of 120-volt, 15-ampere, general lighting branch circuits required for a dwelling unit having a calculated general lighting load of 9,600 VA?
12. In regard to emergency systems, where internal combustion engines are used as the prime movers, they shall NOT be solely dependent on a public utility gas system for their fuel supply, unless _____ .
13. Wall-mounted 15- and 20-ampere, 125-volt receptacle outlets installed in dwelling units shall not be counted as part of the required number of receptacle outlets where they are located MORE than _____ above the floor.
14. Where ambient temperature and the number of current-carrying conductors in the raceway are not a factor, what MINIMUM size 75C copper ungrounded (phase) feeder conductors are required to supply 200 ampere rated continuous load?
15. Apply the general method of calculation and determine the demand load, in kW, on the ungrounded service-entrance conductors for one (1) household electric range rated 20,800 watts.
16. Given: A busway has an ampere rating of 1,100 amperes. What is the MAXIMUM standard size overcurrent protection devices that may be used to protect the busway?
17. When sizing overcurrent protection for fire pump motors, the device(s) shall be selected or set to carry indefinitely the ____ of the motor.
18. Ceiling-suspended luminaires (lighting fixtures) or paddle fans located _____ or more above the maximum water level of an indoor installed spa or hot tub shall NOT require GFCI protection.
19. In general, all mechanical elements used to terminate a grounding electrode conductor or bonding jumper to a grounding electrode shall be accessible. Which of the following, if any, is/are an exception(s) to this rule?
I. A connection to a concrete encased electrode.
II. A compression connection to fire-proofed structural metal.
20. Where given the following conditions, determine the MINIMUM size copper branch-circuit conductors with Type XHHW-2 insulation required to supply a roof-top mounted air-conditioning unit with a full-load ampere rating of 45 amperes.

1) The conductors are to be installed in an EMT, exposed to sunlight 3 in. above the roof-top.
2) The ambient temperature on the rooftop is 115F.
3) The A/C unit is operating at a 3-phase voltage of 208; 3 conductors are considered current-carrying.
4) The terminations of the A/C unit are rated for 75C.
21. Fuses shall NOT be permitted to be connected in parallel where _____.
I. they are factory assembled and listed as a unit
II. they are installed by a technician on the jobsite
22. Each multiwire branch circuit shall be provided with a means that will simultaneously disconnect _____ at the point where the branch circuit originates.
23. Determine the Maximum ampere setting permitted for an overload protective device responsive to motor current, where used to protect a 20 hp, 240-volt, 3-phase, induction type ac motor with a temperature rise of 48C and a full-load ampere rating of 54 amperes indicated on the nameplate. Assume the initial setting of the overload protective device selected is not sufficient to start the motor, therefore modification of this value is necessary.
24. A single electrode consisting of a ground rod, pipe, or plate that does not have a resistance to ground of 25 ohms or less, shall be supplemented by one (1) additional electrode. Which of the following listed is/are approved for this purpose?
25. What classified (hazardous) location(s), if any, does the NEC' permit flexible metal conduit (FMC) for connections to motors?
I. Class I, Division 2
II. Class II, Division 1
26. At carnivals and fairs, service equipment shall not be installed in a location that is accessible to unqualified persons, unless the equipment _____.
27. Nonmetallic surface extensions shall be permitted to be run in any direction from an existing outlet, but NOT within _____ of the floor level.
28. The NEC permits a building to have more than one service when:
I. the load requirements of the building are at least in excess of 800 amperes.
II. the building is separated by firewalls with a four-hour rating.
29. In the garage of a dwelling unit, a 125-volt, single-phase, 15-ampere, receptacle installed in the ceiling provided for the garage door opener must be _____ .
I. a single receptacle
II. FCI protected for personnel
30. Cartridge fuses in circuits over _____ to ground shall be provided with a disconnecting means on their supply side.
31. Outlets supplying permanently installed swimming pool pump motors from single-phase, 15- or 20-ampere, 120- or 240-volt branch circuits, shall be provided with GFCI protection _____ .
32. The branch circuit conductors supplying a 240-volt, single-phase, 15 kW rated fixed electric space heater provided with a 10 ampere blower motor are required to have an ampacity of at LEAST _____ .
33. A commercial kitchen is to contain the following listed cooking related equipment:

* one - 19 kW range
* one - 5.0 kW water heater
* one - 0.75 kW mixer
* one - 2.5 kW dishwasher
* one - 2.0 kW booster heater
* one - 2.0 kW broiler

What is the demand load, in kW, on the ungrounded (phase) service-entrance conductors after applying the demand factors for the kitchen equipment?
34. A metal underground water pipe is permitted for use as a grounding electrode where the water pipe is in direct contact with the earth for at LEAST _____ or more.
35. A kitchen with a total demand load of 54,000 VA is to be added to an existing church. The electrical system is 208Y/120-volts, 3-phase. What MINIMUM size THWN copper feeder conductors are required for the kitchen addition?
36. A feeder at a school welding shop is to supply the following listed 240-volt, single-phase transformer arc welders all with a 50 percent duty cycle.

* two (2) with 60 amperes rated primary current
* two (2) with 50 amperes rated primary current
* two (2) with 40 amperes rated primary current

The feeder is required to have an ampacity of at LEAST _____.
37. Rigid polyvinyl chloride conduit (PVC) LARGER than trade size _____ shall not be used.
38. What is the MAXIMUM balanced demand load, in VA, permitted to be connected to a new service of a commercial building where given the following conditions?
I. The service is 208Y/120-volts, 3-phase, with a 600 ampere rated main circuit breaker.
II. The maximum load must not exceed 80 percent of the ampere rating of the main circuit breaker.
39. Splices and taps in surface nonmetallic raceways without covers capable of being opened in place shall be _____.
40. Openings around electrical penetrations of a wall of a designated information technology room are required to be _____ .
41. Given: A four (4) unit multifamily dwelling has a 14 kW, 240-volt, single-phase, electric range installed in each dwelling unit. Apply the general method of calculation for dwellings and determine the demand load, in kW, on the ungrounded (phase) service-entrance conductors for the electric ranges.
42. Refer to the previous question; apply the optional method of calculation for dwellings to determine the demand load, in kW, on the ungrounded service-entrance conductors for the electric ranges.
43. Where size 4/0 AWG multiconductor cables, rated for 2000 volts or less, are placed in a ladder type cable tray, what is the MAXIMUM fill area, in square inches, of 9 inch wide cable tray?
44. Where installed for a commercial occupancy, determine the MINIMUM size THWN copper conductors required from the terminals of a 3-phase, 277/480-volt, 4-wire, 200 kW generator to the first distribution device(s) containing overcurrent protection. Assume the design and operation of the generator does NOT prevent overloading.
45. Enclosures containing circuit breakers, switches and motor controllers located in Class II, Division 2 locations, shall be _____ or otherwise identified for the location.
46. An electrical system comprised of multiple power sources is known as _____.
47. In _____ of dwelling units all 120-volt, single-phase, 15- and 20-ampere branch circuits supplying outlets or devices are to be provided with AFCI protection.
I. kitchens
II laundry areas
48. Given: A one-family dwelling to be built will have 4,000 sq. ft. of livable space, a 600 sq. ft. garage, a 400 sq. ft. open porch, a 2,000 sq. ft. unfinished basement (adaptable for future use), three (3) small-appliance branch-circuits and a branch circuit for the laundry room. Determine the demand load, in VA, on the ungrounded service-entrance conductors for the general lighting and receptacle loads using the standard method of calculation for a one-family dwelling.
49. Determine the MINIMUM size Type SOW flexible cord that may be used to supply a 30 hp, 3-phase, 480-volt, continuous-duty, ac motor from the motor controller to the motor terminations. Assume voltage-drop and elevated ambient temperature are not considerations.
50. Portable structures for fairs, carnivals and similar events shall not be located under or within a MINIMUM of _____ horizontally of conductors operating in excess of 600 volts.
51. Flexible cord and cables shall be permitted to be attached to building surfaces _____.
52. In regard to outside branch circuits of overhead spans of open individual conductors for 1000 volts or less up to 50 feet in length, the NEC mandates the conductors to be NOT less than _____ copper in size.
53. As defined in the NEC, a controller is any switch or device that is normally used to _____.
54. The MINIMUM spacing required between live uninsulated metal parts in feeder circuits of 480-volt industrial control panels and bare metal parts of the enclosure is _____.
55. The insulated conductors of Type TC cables shall be in sizes _____ to 1000 kcmil copper, nickel, or nickel-coated copper.
56. All swimming pool electric water heaters shall have the heating elements subdivided into loads not exceeding 48 amperes and protected at NOT over _____ .
57. In regard to emergency and legally required standby systems, transfer switches shall be _____ and approved by the authority having jurisdiction.
58. Where Type SE service-entrance cable is used for interior wiring as a substitute for Type NM cable for branch circuits and feeders, and installed in thermal insulation, the ampacity shall be in accordance with the _____ conductor temperature rating.
59. The continuity of a grounded conductor shall NOT depend on connection to a _____.
60. Where a receptacle outlet is removed from an underfloor raceway, the conductors supplying the outlet shall be _____ .
61. What is the MINIMUM dimension required by the NEC for a working space containing exposed live parts on both sides of the equipment that will require examination and maintenance of the equipment when energized and operating at 480-volts between conductors?
62. Where a mobile home park has 25 mobile home lots calculated at 15,000 VA each, determine the MINIMUM required ampacity required for the ungrounded service-entrance conductors.
63. Given: A 3-phase, 150 kVA transformer with a 208Y/120-volt secondary has an existing load of 212 amperes on each of the ungrounded phases. What is the MAXIMUM load, in amperes, that may be added to each of the ungrounded secondary phases?
64. In regard to an isolated grounding type receptacle, the reason the insulated isolated grounding conductor is not bonded to the outlet box is _____ .
65. Branch circuits that supply electric signs containing fluorescent lighting ballasts shall be rated NOT to exceed _____.
66. Type CMP communications cable of NOT more than ____ in length shall be permitted in ducts used for environmental air if they are directly associated with the air distribution system.
67. The disconnecting switch or circuit breaker for electric signs and outline lighting systems shall open all _____ conductors simultaneously on multi-wire branch circuits supplying the sign or outline lighting system.
68. In dwelling units, hallways of at LEAST _____ or more in length shall have at least one 125-volt, 15- or 20-ampere receptacle provided.
69. Where constant wattage heating cables are installed in concrete floors, the cables shall NOT exceed ____ per linear foot per cable.
70. In general, the NEC does not mandate the maximum number of circuit breakers a panelboard may contain. An exception to this rule is ______, which is limited to no more than 42 overcurrent protection devices.
71. When the water reaches the height of the established electrical datum plane for an irrigation pond, the service equipment must ______.
72. General-use dimmer switches shall ONLY be used to control _____, unless listed for the control of other loads.
73. Lampholders shall be constructed, installed, or equipped with shades or guards so that combustible material is not subjected to temperatures in EXCESS of ______.
74. Pendant conductors having a length of at LEAST ______ or more shall be twisted together where not cabled in a listed assembly.
75. When installed in a metal enclosure, the grounding electrode conductor for a Type 1 surge-protective device (SPD) of 1 kV or less shall be _____.
76. At least one structural member of a building or structure that is direct contact with the earth for at LEAST _____ or more, with or without concrete encasement shall be permitted to be used as a grounding electrode.
77. The circuit supplying an autotransformer-type dimmer installed in theaters and similar places shall NOT exceed _____ between conductors.
78. A twelve (12) unit apartment building will have a 5,500 watt electric clothes dryer placed in each apartment. Apply the general method of calculation and determine the demand load, in VA, on the ungrounded service-entrance conductors for the dryers.
79. Each luminaire installed in Class III, Divisions 1 and 2 locations shall be clearly marked to show the maximum wattage of the lamps that shall be permitted without exceeding an exposed surface temperature of _____ under normal conditions of use.
80. Conductors supplying a continuous-rated, varying-duty motor shall have an ampacity of NOT less than _____ of the motor nameplate current rating.
81. What is the MAXIMUM spacing allowed for supporting Type MC cable with size 12 AWG conductors where used as a branch circuit in a manufactured wiring system?
82. Receptacles or receptacle cover plates supplied from the essential electrical system in a hospital, shall be identified by _____ .
83. What is the MAXIMUM standard size circuit breaker that may be used for overcurrent protection of size 4/0 AWG THWN copper conductors that are not serving a motor load?
84. A multiwire branch circuit supplying a motor fuel dispensing pump, shall be provided with a switch that will disconnect _____ .
85. The depth of the working space in front of a 120-volt, single-phase, fire alarm control panel (FACP) is required to be at LEAST _____.
86. Where an air conditioning unit is supplied with size 6 AWG CU conductors installed in a PVC conduit and protected by a 60 ampere circuit breaker, the MINIMUM size CU equipment grounding conductor permitted for this installation is _____ .
87. Which of the following is NOT required to be marked on the nameplate of a transformer?
88. When combination surface nonmetallic raceways are used for both signaling and for power and lighting circuits, the different systems shall be _____.
89. Where explosionproof equipment is provided with metric threaded entries, which of the following methods is approved to adapt the entries from metric threads to NPT threads?
90. An indoor located 100 kVA, dry-type transformer with a 4,160-volt primary is required to have a clearance of at LEAST _____from combustible material.
91. A clearance of NOT less than _____ must be maintained from the maximum water level of a permanently installed swimming pool and messenger-supported tri-plex service-drop conductors of 0-750 volts.
92. Where an apartment complex has a calculated connected lighting load of 205.4 kVA, what is the demand load, in kVA, on the ungrounded service-entrance conductors where applying the standard (general) method of calculation? Given: Each dwelling unit in the complex has cooking facilities provided.
93. Cord-and-plug connected high-pressure spray washing machines shall be provided with GFCI protection for personnel when operating at _____.
I. single-phase, 120-volts, 30 amperes
II. 3-phase, 208-volts, 50 amperes
94. For the purpose of sizing branch circuits for fixed storage-type water heaters with a capacity of 120 gallons or less, the water heater shall be considered ____ .
95. When supplying a 36,000 VA, 240-volt, single-phase load in an area where the ambient temperature reaches 119F, determine the MINIMUM size 75C rated copper conductors required to supply the load.
96. Color coding shall be permitted to identify intrinsically safe conductors where they are colored ____ and where no other conductors of the same color are used.
97. For an overhead type motor fuel dispensing device, the space within the dispenser enclosure shall be classified as a _____ location.
98. Where exceptions are not to be applied, determine the MINIMUM required length of a junction box that has a trade size 3 in. conduit containing four (4) size 250 kcmil conductors, pulled through the box for a 90 angle pull.
99. An approved method of protection for equipment installed in Class I, Zone 0, hazardous locations is _____ .
100. Electrical service and feeder conductors for electrified truck parking spaces at a truck plaza shall be calculated on the basis of NOT less than _____ per electrified truck parking space.