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Electrifying Foundations: Your Essential Guide to Mastering Chapter 1 of Year 2 Electrical Engineering, A Comprehensive Exam Study Guide 100% Certified and Verified by Expert. Latest Updated 2025/2026.
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The purpose of the NEC is the practical safeguarding of __ from hazards arising from the use of electricity. - ansPeoples and buildings Annex H in the NEC - ansIs to used for information on unless specifically adopted by the local AHJ A continuous load is any load that expected to operate for - ans3 hours or more. To assist in the proper application of the NEC a term that appears in more than one article is defined in - ansArticle 100 A door chime is an example of a device - ansFalse Which of the following statements is true for an individual branch circuit that is run in a conduit with other circuits? - ansIt can charge a neutral with another circuit The exact code reference that requires electrical equipment to be securely fastened to the surface on which it is mounted is - ans110.13(A) The NEC permits the attachment cord and plug that is attached to an air compressor to be used as the disconnecting means. How does section 100.22 require that this disconnecting means be identified? - ansIt's purpose is obvious and not required to be marked. B-phase on a 120/240 volt 3-ph, 4-wire system is called the ___ leg. - ansHigh stinger wild. Section __ in the NEC specifies that all 120-volt receptacles in the kitchen of a cafeteria are to be gfci protected - ans210.8(B)(2) How many 20-amp kitchen countertop Receptacle - ans In NEC article 500.8, equipment marked for use in a class 1 locations and has a marked temperature classification of T3B is suitable for use in environments with a maximum surface temperature of - ans329F Protection against __ is addressed by the requirements in the NEC - ansFault currents effects, Thermal, Electric shock. Which of the following installations Are covered by the NEC? - ansNone of the above Is the conduit between the lighting peoples covered by the NEC? The street lightning and conduit were installed in the utility easement as shown in the drawing a the right and is under the control of CenterPoint energy.(utility company) - ansNo. Chapter 8 in the nec covers ___ and is independent of the other nec chapters. Provisions in other chapters do not apply unless directly referenced in chapter 8 - ansCommunication systems The authority having jurisdiction has the responsibility - ansFor enforcing the NEC, For approving equipment installations, also for granting special permission Annex ___ in the NEC contains examples of load calculations for dwellings - ansD How long does something need to run to be a continuous load - ans3 hours ___ equipment is constructed so that water will not enter it. - ansWatertight A 1900 (4_square or 4x4 square) box with a cover that is installed above a drywall ceiling is considered - ansNot accessible A fluorescent luminaire is an example of a device - ansFalse The illuminated marquee sign for a theatre would be considered to be a ___ load - ansContinuous If a motor and the disconnecting means ( safety switch) are located in the same room and 60 feet apart, these___ considered to be within sight (of each other) per the NEC - ansAre not Which of the following conductor materials are recognized by the NEC - ansAluminum, copper, copper-clad aluminum (all of these)
Improper electrical terminations lead to increased - ansCircuit resistance, also voltage dropped across the terminations Some wire nuts are listed for direct burial underground - ansTrue Per section 110.26(A)(1) in the NEC, where the wall opposite a panel board is a metal door condition ___ applies to the clearance requirements - ans The neutral of an electrical system is always carrying the unbalanced current of that system - ansTrue The NEC permits the insulation for an ungrounded conductor to be in color. - ansAnything that isn't green white or gray All 120- volt kitchen receptacles in the kitchen of a school cafeteria are required by the NEC to be GFCI protected - ansTrue Refer to NEC 500.8 generally, equipment for use in hazardous locations shall be marked to show the environment for which it has been evaluated. Equipment that is not marked to indicate a division or is marked as division 1 is ____ - ansSuitable for both divisions 1 and 2 The class and material group classification where combustible metal dusts such as magnesium are present is - ansClass 2, Group E In a hazardous location, class 1 is a location that - ansA contains flammable gases In a hazardous locations, class 3 is a location that - ansContains ignitable fibers or flyings A location in which easily ignitable fires are manufactured is a - ansClass 3, division 1 A location in which ignitable flammable, flammable liquidproduced vapors - ansClass 1 Is the amount of electricity required at a given time - ansDemand For the calculations required in article 220, the total area of an occupancy is determined from the __ dimensions of the building or structure - ansOutside Feeders for several motors are calculated using the sum of the table flics of all motors plus ____ % of the largest motor - ans125% For a single-family dwelling with six appliance load, demand factors may be applied to ___ of these loads using the standard calculation - ansAll six Using the standard calculation, four or more appliance which are fastened-in- place in a one- family dwelling are computed at of the total load for all appliances. - ans75% Service equipment is the "point of division" between the ___ and ___. - anssupply (line) side, load side When planning a service installation, which of the following should be considered? - ansall of these A panelboard that is marked "suitable only for use as service equipment" ___. - ansusually has the neutral bar factory bonded to the enclosure A service (meter and fused safety switch) is built on a wooden pole that is located 200' from the building it serves. Does the NEC® consider the pole to be a structure? - ansYes The smallest copper service lateral conductors that can be installed for a service are ___ AWG. - ans Any equipment that is installed between the utility supply and the service overcurrent protective device(s) is on the ___ side of the service. - anssupply (or line) When special permission is granted by the AHJ, this is in the form of - ansa written document Where a service (meter and fused safety switch) is built on a rack that is located 200' from the building it serves, the rack is considered a structure per the NEC®. - ansTrue
The service disconnecting means for a 3-phase service is permitted to consist of __ - ansa. not more than 6 separate circuit breaker enclosures, each with a 3-pole breaker b. a fusible switchboard with a maximum of 6 switches c. a main breaker panelboard with eight individual 3-pole circuit breakers The smallest main breaker that can be installed in a 24-circuit service panel on a single- family dwelling is ___ amps. - ans The smallest service that can be installed on a barber shop is ___ Amps. - ans Service entrance conductors are protected against ___ currents. - ansoverload Copper conductors are installed between a main breaker service panel and a main lug only subpanel. The conductors between the two panels are protected against ___ currents. - ansa. ground-fault b. overload c. short-circuit Which of the following requires that a GFPE device be installed? - ans480/277-volt, 3Ø, 4- wire switchgear with a 1000-A main breaker The maximum number of 3-pole circuit breakers used as service disconnects permitted in a 3Ø panelboard is ____. - ans In a class II location, ventilating pipes for generators shall be of metal not less than ___ inches in thickness or of equally substantial noncombustible material. - ans.021 in Which wiring type is not permitted in Class 2, Division 1 locations? - ansEMT In a class II, division I location where a raceway provides communication between an enclosure that is required to be dust-ignitionproof and one that is not, a vertical raceway not less than ___ feet long and extending downward from the dust-ignitionproof enclosure is a suitable means to prevent the entrance of dust. - ans5 Ft There shall be no uninsulated exposed parts, such as electrical conductors, buses, terminals, or components, that operate at more than ___ volts in a dry location in Class 2, division 1 and 2 locations. - ans30 V ___ when current flows in a conductor. - ansa. Heat is generated b. A magnetic field is created When a load is operating, heat is generated in the circuit conductors. - ansTrue Which of the following conductor installations are in locations that are considered to be wet?
Fuses installed for motor branch circuits generally are of the dual-element time-delay type because these OCPDs can hold ___ current for a short period of time that is long enough to get the motor up to speed. - ansoverload Time-delay fuses are also known as ___ fuses. - ansdual-element When a tripped breaker is found, you should ___. - ansdetermine the cause of the trip and correct it before resetting the breake When PVC is installed in a concrete slab, this is considered to be a ___ location. - answet A(An) ___ conductor can be used for a grounded conductor where it is installed in conduit with branch circuit conductors. - ansinsulated A bare conductor can be used for a grounding electrode conductor where it is installed between a service panel and a ground rod - anstrue A bare copper conductor can be used for ___ when it is installed in EMT as part of a branch circuit. - ansa grounding conductor Two parallel sets of conductors are to be connected to lugs in a transformer and to lugs in a fused safety switch. Does the NEC® permit the conductors in the transformer to be connected with single lugs and the conductors in the safety switch to be connected with double lugs - ansyes Which of the following affects how much current a wire can carry? - ansa. insulation type b. conductor material c. conductor size d. surrounding air temperature Which of the following are characteristics of THHN/THWN insulation? - ansa. It is heat- resistant. b. It can be installed in wet, damp, or dry locations. c. It is flame-retardant. d. It is moisture-resistant. The largest solid wire that can be installed in a run of EMT as branch circuit conductors is ___. - ans Two ungrounded branch circuit conductors are installed to serve a load. These are installed in PVC. The 8 AWG copper ungrounded conductors are permitted to be ___. - ansstranded Per the NEC®: Generally, conductors are required to be insulated. - ansTrue Which 2 AWG conductor has a higher resistance? - ansaluminum What is the minimum size THHN/THWN wire permitted to serve a load that will draw 47 amps? The load will operate for about 5 hours at a time. The branch-circuit OCPD is a circuit breaker that is rated for 75°C. - ans6 AWG A piece of equipment has a nameplate rating of 195 amps. The smallest wire that can be installed to serve this load where operated continuously is ___ AWG or KCMIL. The OCPD has terminations rated at 75°C. - ans What minimum size conductors are required to feed a 16000-watt, 240-volt electric furnace operated at 240 volts? Size the conductors per 424.3(B). The branch-circuit OCPD is a circuit breaker that is rated for 75°C. - ans Inside a 277/480-volt, 3-ph, 4-wire panelboard, a 1/0 conductor that is connected to a circuit breaker can carry ___ amps of current. - ans A 4/0 AWG conductor that is connected to a circuit breaker in a 120/208-volt, 3-ph, 4-wire panelboard can carry ___ amps of current inside the panel. - ans
A feeder needs to be installed to supply power to a load that will draw 900 amps. The circuit breaker will be rated at 900 amps. There will be 3 parallel conduits run for the feeder. You will need to install at least ___ AWG or kcmil conductors in each conduit. - ans The largest OCPD that can be installed to protect 4/0 AWG THHN/THWN circuit conductors is rated at ___ amps. The connected load draws 180 amps and will NOT be operated continuously. The OCPD has terminations rated at 75°C. - ans What is the maximum size branch-circuit OCPD permitted to serve a single load that is connected with 4 AWG THHN/THWN wire? The branch-circuit OCPD is a circuit breaker that is rated for 75°C. The connected load is NOT continuous and will draw 83 amps. - ans A branch circuit serving a load is protected with 40-A fuses in a 60-A safety switch. This branch circuit has a rating of ___ amps. - ans Where a branch circuit is protected with a fused safety switch, the ___ determines the rating of the branch circuit. - ansampere rating of the fuses In a 3Ø, 4-wire branch circuit where one neutral is "shared" among all three "hots," it is possible for the neutral to carry more current than any one ungrounded conductor. The circuits serve nonlinear loads. - ansTrue A 120/240-volt, 1Ø, 3-wire multiwire branch circuit is connected to a "split-wired" double single-pole switch as shown here. These are sometimes called dougle or stack switches. Each of the two switches (mounted on the same yoke) will serve a separate 120 - volt lighting load. The branch-circuit OCPD/disconnect for these circuits is permitted to be ___. - ansa. a 2-pole circuit breaker b. two single-pole circuit breakers with identified handle ties c. a 2-pole fused safety switch Where a 120/240-volt, 1Ø, 3-wire multiwire branch circuit is connected to a "split-wired" duplex receptacle in a bakery, the branch-circuit OCPD/disconnect is permitted to be ___. I. two single-pole circuit breakers without handle ties II. a 2-pole fused safety switch III. a 2-pole circuit breaker - ansII or III only An 8.2 kVA load (rated to operate at the applied voltage) is connected to a branch circuit that is fed from a 2-pole 35 A breaker in a 120/240-volt, 3Ø, 4-wire panelboard. Will the breaker trip due to overload? - ansNO A 15-amp, multiwire branch circuit is connected to breakers 1 and 3 in a 120/208-volt, 3Ø, 4- wire panelboard. ___ if the "hots" from breakers 1 & 3 are connected to a 2800-watt load. - ansThe load will operate normally and the breaker will not trip Two lighting circuits are supplied from a multiwire branch circuit that originates in a 120/ volt, 1Ø, 3-wire panelboard. Two, 20 Amp, 1-pole breakers are installed in spaces 22 & 24 for the multiwire circuit. Circuit 22 has 2600 watts of lights connected to it, and Circuit 24 has 2100 watts of lights connected to it. Somewhere in the circuit the "hot" from breaker 22 and the "hot" from breaker 24 touch together. Which of the following should happen to Circuit 22? - ansA short circuit will occur and the breaker will trip. A branch circuit, where 2 AWG conductors are installed, serves a single load that will not operate more than 3 hours. These conductors can be protected by a circuit breaker with a rating no greater than ___ Amps. - ans
A 19.7 kW boiler (water heater) is operated at its rated voltage when connected to a 2-pole breaker in a 120/240-volt panel. The smallest conductors permitted to feed this equipment are used. The maximum size OCP permitted is ___ Amps. - ans The largest 3-pole circuit breaker that can be used to protect a 10 AWG copper Type SJTO flexible cord is ___ A. - ans When ___ touch together, this is a ground fault. - ansan ungrounded circuit conductor and the metal conduit You are going to pull in five dedicated (individual) branch circuits into one metal conduit. Each circuit supplies power to a 120-volt load. The ungrounded conductors will be connected to breakers 2, 4, 6, 8, & 10 in a 120/240-volt, 1Ø, 3-wire panelboard. Per the NEC ®, the fewest number of neutral conductors you can install for the branch circuits is ___. - ans In a panelboard, 8 AWG feeder conductors are connected to a 2-pole, 50-amp circuit breaker. The feeder conductors enter a pull box where several other conductors are connected to them. If 8 AWG conductors are connected to the feeder, the 8 AWG conductors are ___. - ansfeeders In a panelboard, 3/0 AWG feeder conductors are connected to a 2-pole, 200-amp circuit breaker. The feeder conductors enter a pull box where several other conductors are connected to them. If 2 AWG conductors are connected to the feeder, the 2 AWG conductors are ___. - anstaps Where installed in a 3-pole, 600-volt fused safety switch, the minimum number of fuses required to protect a 277/480-volt, 3-ph, 4-wire branch circuit is ___. - ans Typically, OCPDs are connected in ___ with the circuit conductors. - ansseries A circuit breaker panel is permitted to be installed in which of the following locations? - ansI. a restroom in an office building II. a mechanical room in a hospital Can a safety switch rated for 250 volts be used as the disconnecting means for a 208-volt circuit? - ansyes Which of the following safety switches is (are) permitted to be used as the disconnecting means for a 240-volt, 1Ø water heater? - ansI. 250-volt, 2-pole II. 600-volt, 3-pole III. 250- volt, 3-pole You need to get power to a 208-volt load. Your available power is from a 120/240-volt, 3Ø, 4 - wire panelboard. Is it permitted for you to run a branch circuit from the neutral bar and a 1- pole circuit breaker installed in breaker space #4? The CB has a 120-volt rating. - ansNO The ability of an overcurrent device to safely open under fault conditions is referred to as its ___ rating. - ansinterrupting Generally, the NEC® permits a circuit breaker to carry ___ percent of its rating where it supplies a load that is not operated for more than 3 hours. - ans Plug fuses and fuseholders can be used to protect circuits on ___ systems. - ansII. 120/240- volt, 1Ø, 3-wireIII. 120/208-volt, 3Ø, 4-wire When plug fuses are used on all new installations such as in a disconnect switch for a clothes dryer, the fuses must be ___. - ansType S Instantaneous-trip circuit breakers can be installed _ - ansas a part of listed combination with a motor controller Stems of metal conduit for pendant luminaires in Class III, Division 2 locations shall be braced against lateral displacement if the stems are longer than ___ inches. - ans
circuit will take ___ time for the circuit breaker to open when a ground fault occurs. - ansmore You are to connect a 3-phase air handler unit (AHU). You decide to use 3 feet of? inch FMC (Flexible Metal Conduit or flex) since you realize that it has a motor and as such will tend to vibrate. Per the NEC ®, do you need to install an EGC (Equipment Grounding Conductor) with the FMC between the disconnect switch and the AHU? The disconnect has a 30-amp rating but is fused at 20 amps. - ansYes A 400-A, 3Ø main lug panel will be fed with one conduit from a 300-Amp, 3-pole breaker in a 120/208-volt, 3-ph, 4-wire panelboard. The feeder will consist of three 350 kcmil conductors (one for AØ, one for BØ, and one for CØ) plus a grounded conductor.Refer to Scenario 205.2. The smallest EGC that can be run is a ___ AWG. - ans Where lubrication and vehicle servicing is done at minor repair garages, the space below the floor level in a ventilated pit shall be ___. Exhaust ventilation is provided at a rate of not less than 0.3 m3/min/m2 (1 cfm/ft2) of floor area at all times that the building is occupied. - ansunclassified Where major repair garages service vehicles that are fueled by lighter-than-air fuels such as natural gas or hydrogen, the area within ___ of the ceiling shall be considered unclassified where ventilation of at least 1 cfm/ft2 of ceiling area is provided. - ans18 inches In major repair garages, where vehicles ___ are repaired or stored, the area within 450 mm (18 in.) of the ceiling shall be considered unclassified where ventilation of at least 1 cfm/sq ft of ceiling area taken from a point within 450 mm (18 in.) of the highest point in the ceiling is provided. - ansthat are fueled with lighter-than-air fuels In a minor repair commercial garage, if there is mechanical ventilation providing a minimum of four air changes per hour, the entire floor area shall be: - ansunclassified In a repair garage, which function does not constitute a minor repair - ansPainting In commercial repair garages where electrical diagnostic equipment, electrical hand tools, or portable lighting equipment is used, GFCI protection is required for all ___ receptacles. - ansI. 125-volt, single-phase, 15 and 20-ampere II. 250-volt, single-phase, 30-ampereIII. 250- volt, three-phase, 15- and 20-ampere The Code reference for GFCI protection of receptacles in commercial garages is found at ___. - ansc. 511. ___ persons shall be used to perform any work on live or energized equipment. - ansQualified Written Energized Electrical ___ are required if live parts can not be put in an electrically safe condition. - answork permits When working near live parts, you must know the ___ related to the work. - ansdangers Personal Protective Equipment shall be worn as ___ for the risks involved. - ansappropriate PPE is required for head, face, neck, ___, hands, arms, feet and legs. - ansa. chin b. eyes c. body Qualified Persons need ___ and knowledge of equipment and hazards to work safely. - anstraining A grounding conductor that is installed in a conduit with circuit conductors carries current ___. - answhen a ground fault occurs
Your only available grounding electrode is the metal underground water pipe from the water utility. You are required by the NEC® to have one other grounding electrode for your service. You could use which of the following driven electrodes? - anseither I. 8 ft of trade size 3/4 rigid metal conduit II. 10' by 5/8 inch copper-clad ground rod Thirty feet of 3/8 inch rebar used to reinforce grade beams within a poured building slab ___ permitted to be used as a grounding electrode for a separately derived system or a service. - ansis not The primary purpose of bonding metal equipment enclosures, metal raceways, and the grounded power supply together is to ___. - ansI. cause the quick operation of OCPDs The smallest size copper wire permitted to be used as a main bonding jumper in a 200-A main breaker panelboard is ___ AWG. The panel is fed from a transformer with one set of 3/0 AWG wire. - ans Grounding electrodes made of galvanized RMC (Rigid Metal Conduit) shall ___. - ansI. be at least 3/ 4 inch in diameter Ground rods made of aluminum RMC ___. - anse. shall not be permitted Where a 250 kcmil copper GEC is subject to physical damage, it ___. - anscan be run inside properly supported RMC A 120/240v 1-phase 3-wire service panel is fed with three 1 AWG copper conductors. The minimum size grounding electrode conductors connected to building steel is ______________ AWG. - ans For a 225-amp service where 4/0 AWG service entrance conductors are installed, the smallest main bonding jumper permitted is ___ AWG. - ans A 120/240-volt, 1-ph, 3-wire service is to be run to serve 125-A, main breaker Panel B. As shown, one conduit will be installed for the service. The conduit will contain two 1 AWG conductors for the ungrounded conductors. Most of the loads are 240-volt, 1Ø phase without neutrals. The smallest MBJ that can be installed in Panel B is a ___ AWG. - ans has a 175-amp main breaker. The conduit contains 2/0 conductors. The minimum size main bonding jumper is ___ AWG or kcmil. - ans What is the smallest size copper wire permitted to be used as a main bonding jumper in a 400 - A main breaker panelboard? The panel is fed from a transformer a single conduit containing four 500kcmil conductors. - ans1/0 AMG Each circuit, leading to or through motor-fuel-dispensing equipment for remote pumping systems, shall be provided with a disconnecting means that will simultaneously disconnect all conductors of the circuits, including the grounded conductor. ___ are not permitted for such required disconnecting means. - ansd. Single-pole breakers utilizing handle ties Where a conduit emerges from the earth or concrete under a gasoline pump, a seal must be installed ___ after the conduit emerges for the earth or concrete. - ansas the first fitting All conductors of circuits are required to be ___ on circuits leading to or through dispensing or remote pumping equipment. - anssimultaneously disconnected Where compressed natural gas dispensers are located under a canopy or enclosure that prevents the accumulation or entrapment of ignitible vapors, electrical equipment ___. - ansshall not be required to meet Class I, Division 2 hazardous location requirements A location that is 9 feet from a liquefied natural gas dispenser enclosure is ___ location. - ansa Class I, Div 2
the front yard. The minimum depth the conduit must be below the present dirt surface level (future driveway) is ___ inches. - ans Refer to Figure 207.14. The wiring method is RMC. The minimum distance permitted beneath the sidewalk at Point A (from the bottom of the 4" thick sidewalk to the top of the conduit) is ___ inches. - ans Where covered with stabilized sand to prevent physical damage, Type ___ cable is permitted to be directly buried in a trench underground. - ansI. UF II. MI Which of the following are permitted to be buried in a trench underground? The wiring will be covered with stabilized sand to prevent physical damage. - ansType MI cable Electrical wiring that is installed in and under aircraft hangar floors shall comply with the requirements for a ___ location. - ansc. Class I, Division 1 All fixed wiring in an aircraft hanger, but not installed in a Class 1 location shall be installed in metal raceways or shall be Type MI, ______ , or MC cable. - ansTC Buried raceways and cables under Class I locations in bulk storage plants shall be considered to be within a ___ location. - ansd. Class I, Zone 1 In aircraft hangars where electrical diagnostic equipment, electrical hand tools or portable lighting equipment are used, GFCI protection is required for all ___ receptacles. - ansI. 125- volt, single-phase, 15 and 20-ampere II. 250-volt, single-phase, 30-ampere III. 25 0 - volt, three-phase, 15- and 20-ampere Where non-metallic sheathed cable is used for underground wiring in a bulk storage plant, an equipment grounding conductor ___ electrical continuity of the raceway system and the grounding of all non-current-carrying metal parts. - ansshall be included to provide The chemical distributor, manufacturer, or importer shall ensure that each container of hazardous chemical leaving the workplace has the identity of the hazardous chemical. - ansa. labeled b. tagged c. marked Chemical manufacturers and importers shall obtain or develop SDS sheets for each hazardous chemical they produce or import. These SDS sheets shall be written in ___. - ansEnglish Employers shall ensure that employees are provided with ___ to the extent necessary to protect them in the event of a spill or leak of a hazardous chemical. - ansa. training b. information At each workplace, employers shall ___ a written hazard communication program. - ansa. develop b. implement c. maintain Written Haz Com programs shall describe how the labels and other forms of warning, SDS sheets, and employee information and training will be met. - ansTrue A written Haz Com program requires a list of chemicals known to be present in the workplace, and the methods the employer will use to inform the employees of these hazards.
Conductors that are enclosed in Schedule 80 PVC ___. - ansa. are protected from physical damage b. are capable of being removed A 4 square box (1900) with a 1-gang plaster ring is to be flush mounted behind a sheetrock wall for a receptacle. 1/2" FMC will be installed in the wall and connected to the box. Does the NEC® permit a 90° flex connector to be used at the box? Select one: - ansNo Which of the following is an example of a raceway? - ansII. LFMC III. RMC Does the NEC ® permit the installation shown above at X in Figure 208.1? The box is supported only by the conduits. The distance from the top of the head track to the bottom of the 4-SQ box is 2 inches. Both conduits are EMT and are attached to the box with steel compression connectors (not visible in drawing). - ansno When a 1900 (4" square) box does not contain devices it is permitted to be supported by EMT if all three of the following conditions are met:1) the EMT is stubbed out of a block wall,2) the box is within 3 feet of the wall, and3) at least two other EMTs enter the box to provide additional support. - ansFalse A PAR lampholder is installed in a 1-gang weatherproof "bell" box. This box is permitted to be supported by RMC and threadless connectors where ___.I. no more than 18" of RMC is stubbed out of the ground and enters the box II. at least two RMCs are stubbed up out of the ground into the bottom of the box - ansneither I nor II 26 feet of Type AC cable is used to connect a 2 x 4 lay-in fluorescent luminaire to a "home run" box as shown above in Figure 208.2. Supports #1 & #2 are as far from the connectors as the NEC ® permits. You will have to install ___ additional supports between #1 and #2. - ansmore than 3 MC cable is used to connect a 2 x 4 lay-in fluorescent luminaire to a "home run" box as shown above in Figure 208.2. The length of the cable between the box and the luminaire is 26 feet. Where supports #1 & #2 are as far from the connectors as permitted ___ additional supports are required between #1 and #2. - ans You are to surface-mount 39' of 12-2 MC cable on a wall between two boxes as shown above in Figure 208.11. You will use 1-hole straps to securely fasten the cable to the wall. The minimum number of straps required is ___. - ans You are to surface mount 128' of EMT on a wall between two boxes as shown above in Figure 208.11. You will use 1-hole straps to securely fasten the EMT to the wall. The minimum number of straps required is ___. - ans Refer to Figure 208.12, shown above. You will need at least ___ straps to support the conduit between enclosures A & B. Trade size 2 IMC with threaded couplings and connectors is used. You will cut and thread the conduit as required. The distance from enclosure A to B is 123 feet. - ans The NEC® states that contact of dissimilar metals be avoided where practicable. The Code reference that specifically permits steel threaded rigid couplings to be used with aluminum rigid metal conduit is ___. - ans344. A section of 3/4-inch flex is used to feed power into the 1900 box and will be connected to one of the connectors shown below. The box will be mounted behind a drywall wall with a 2- gang plaster ring. Two duplex receptacles will be mounted on the box assembly. The NEC® permits ___ to be used. - ansII. the straight flex connector
According to Table 4 in the NEC 2-inch FMC has a total area of 4.909 in2. A 12' run of this flex can be filled with conductors for several circuits. However, the maximum area that can be occupied by the circuit conductors is __ sq. in. - ans1. What is the maximum number of 3 AWG THWN/THHN conductors that can be installed in a trade size 3 EMT that is installed between two enclosures that are 8 feet apart? - ans A switch box is fed with 12-2 MC. FMC ("flex") feeds an H/V/L/NL from the switch box and contains 1 "hot," 3 "switch-legs" and 1 neutral. A 2-gang, 21/2-inch-deep masonry box will be used and will contain the two "dougle or stack switches" shown in Figure 124.104. Will this violate the NEC®? Remember: A "dougle or stack" switch is two, single-pole switches that are mounted on one yoke (mounting strap). - ans A switch box is fed with 12-2 MC. FMC ("flex") feeds an H/V/L/NL from the switch box and contains 1 "hot," 3 "switch-legs" and 1 neutral. A 2-gang, 21/2-inch-deep masonry box will be used and will contain the two "dougle or stack switches" shown in Figure 124.104. Will this violate the NEC®? Remember: A "dougle or stack" switch is two, single-pole switches that are mounted on one yoke (mounting strap). - ansNo Each conduit, connected to the handy box shown above in Figure 208.31, will contain one "hot," one neutral, and one EGC. A duplex receptacle will be installed in the box. The shallowest handy box permitted for this installation is ___. All conductors are 14 AWG THHN/TH - ans21/8 inches deep Each conduit, connected to the switch box shown above in Figure 208.32, will contain one "hot," one neutral, and one EGC. A duplex receptacle will be installed in the box. The shallowest box permitted for this installation is " deep. All conductors are 14 AWG THHN/THWN. - ans2 3/ A switch box, shown above in Figure 208.32, will contain a duplex receptacle and each of the connected conduits will contain 12 AWG THHN/THWN conductors (one "hot," one neutral, and one EGC). The shallowest switch box permitted for this installation is ___ mm deep. - ans `Refer to Figure 208.34. The smallest (volume) junction box that can be used in the installation shown below is a. Conduits #1 and #4 each contain twenty-four 10 AWG wires. Conduits #2 and #5 each contain nine 6 AWG wires. Conduits #3 and #6 each contain sixteen 8 AWG wires. Conduits #7, #10, #9, and #12 each contain twenty-eight 12 AWG wires. Conduits #8 and #11 each contain six 8 AWG wires. All conductors are "wire nutted" inside the box. - ans10" × 10" × 6" deep Refer to Figure 208.36. Which industrial cover/box combination will NOT violate the NEC®? All the conductors are 12 AWG. I. 4 × 11/2 square with 5.0 in3 industrial cover II. 411/16 × 11/4 square box with a 4.2 in3 industrial cover III. 4 × 21/8 square box with a 3. in3 industrial cover - ansII & III only A 4" square box (1900) with a 2-gang plaster ring contains:(one) 12/2 with ground AC cable (BX) with exterior connector (contains hot & neutral + isolated grounding conductor)(one) 14/2 MC cable ( contains a ground) with exterior connector (contains hot & neutral)(one) 14/2 MC cable ( contains a ground) with exterior connector (contains sw. leg & neutral)(one) toggle switch (connected to the 14/2)(one) isolated ground receptacle (connected to the 12/ BX and its isolated ground)The plaster ring has 4.3 cu. in. stamped into the metal. The smallest "1900" box you can use and not violate the NEC® is one that is ___ inches deep. - ans1 1/
The shallow masonry box, shown above in Figure 208.38, will contain two 4-way switches and one three-way switch. Conduit #1 contains five wires, #2 contains four wires, #3 contains four wires, and #4 contains two wires. All conductors are 12 AWG THHN/THWN and are spliced in the box or terminated on the switches. No separate EGCs are installed. Will this installation violate the Code? - ansyes The deep masonry box, shown above in Figure 208.39, will contain three 4-way switches, one single-pole switch, and one three-way switch. Conduits #1 and #4 each contain four 10 AWG wires that are spliced in the box. Conduit #2 contains twelve wires and conduit # contains five wires. Additionally, each conduit contains a ground that equals the size of the circuit conductors in that conduit. The conductors in conduits #2 and #3 are 12 AWG and are terminated on the switches. Will this installation violate the Code? - ansno A switch box will contain the following:(one) isolated ground receptacle(two) 12/2 with ground AC cables (BX) with exterior connectorsThe shallowest switch box you can use for this installation is 3" x 2" x ___". - ans3 1/ A 3-gang masonry box is shown in Figure 107.458. It will have several PVC conduits connected to it. An equipment grounding conductor will be pulled into each PVC. The box will contain three 4-way switches. Twelve "travelers" are pulled into the box along with two other circuit conductors. All conductors are 12 AWG copper THHN/THWN. The box must have a minimum volume of ___ in3. - ans47. For the pull box shown in Figure 208.52, the minimum calculated width is ___ inches. All conductors enter the bottom and exit the right side of the box. - ans33 1/ For the pull box shown in Figure 208.52, the minimum calculated height is ___ inches. All conductors enter the bottom and exit the right side of the box. - ansnone of thes The calculated minimum height (top-to-bottom) of the pull box shown in Figure 208.53 is ___ inches. The conduits considered for this calculation contain conductors that enter this side and exit the adjacent side. - ans The minimum CALCULATED dimension for "height" shown in Figure 208.54 is ___ inches. All conductors enter the left size of the pull box and exit the bottom. - ans For application of Article 516, the interior of any open or closed container of a flammable liquid is considered to be a ___ location. - ansClass I, Zone 0 The interior of any dip or coating tank of a flammable liquid is considered to be a ___ location. - ansa Class I, Division 1 Any spray area in direct path of spray operations is considered to be a ___ location. I. Class I, Zone 1 II. Class II, Division 1III. Class I, Zone 0 - ansI or II only All space in all directions outside of but within 915 mm (3 ft) of open containers, supply containers, spray gun cleaners and solvent distillation units containing flammable liquids are considered to be a ___ location. - ansa. Class I, Division 1 b. Class II, Division 1 c. Class I, Division II When spray application equipment cannot be operated unless the exhaust ventilation system is operating and functioning properly and spray application is automatically stopped if the exhaust ventilation system fails the system is said to be ___. - ansinterlocked For spraying operations conducted within an open-top spray booth, the space ___ vertically above the booth and within ___ of other booth openings shall be considered a Class I, Division 2 location. - ans. 915 mm (3 ft) 915 mm (3 ft)
Does the NEC ® permit a breaker to be mounted in a breaker enclosure such that to turn the breaker "ON" you pull the breaker handle down? - ansNo A 4-gang box and a partition are shown above in Figure 210.4. The box will contain switches A, B, C, and D ( left to right) that are fed from Circuits 1, 3, 5, and 7 (left to right) from a 277/480-volt, 3Ø, 4-wire panelboard. The NEC ® requires partitions between switches - ansall of these A 4-gang box and a partition are shown above in Figure 210.4. The box will contain 4 devices in Positions 1 through 4 ( left to right). A three-way switch is in Position 1 on the far left. This switch controls 120-volt recessed lighting and is fed from Circuit LA-1. Adjacent to (next to) this switch, a receptacle will be installed in Position 2 and is fed from Circuit LA-3. Panel LA is a 120/208-volt, 3Ø, 4-wire panel. In Position 3 will be a single-pole switch fed from Circuit HA-14. Position 4 will contain a four-way switch that is connected to Circuit HA-13. Panel HA is a 277/480-volt, 3Ø, 4-wire panelboard. The NEC ® requires partitions between Positions - ans2 and 3 You are installing a single-pole toggle switch to use as the disconnect for a motor. The information stamped on the switch is "AC only 20 A 120/277 volts." You can use this switch for a 115-volt motor that draws ___ amps at 120 volts. - ans15.6 amps The service entrance conductors are connected to a 200-amp fused safety switch. The switch supplies power to MLO Panel HD-1. Panel HD-1 has feed-through lugs and supplies power to MLO Panel HD-2. Panel ___ is a subpanel. MLO is the designation for Main Lugs Only. - ansboth HD-1 & HD- 2 A circuit breaker is an overcurrent protection device that is designed to automatically open the circuit when a(n) ___ condition occurs. - ansa. overload b. short-circuit c. ground-fault When making up the branch circuit wires to the breakers in a newly installed panelboard, you found that some of the wires were cut too short. Does the NEC ® permit any of these to be spliced with wire nuts so that another piece of wire can be added to be able to reach the breaker or the neutral bar? - ansyes If TWO, individual, single-pole breakers are handle tied and used for a 1Ø, 240-volt circuit, ___. - ansboth "hots" can be manually opened If THREE, individual, single-pole breakers are handle tied and used for a 3Ø circuit, ___. - ansII. all 3 "hots" can be manually opened In a 3Ø panelboard that has vertical busbars, the BØ feeder conductor is connected to the ___ busbar. - anscenter In a 3Ø switchboard that has horizontal busbars, the CØ feeder conductor is connected to the ___ busbar. - ansbottom Panelboards supplied through transformers shall have their overcurrent protection located on the ___ side of the transformer. - anssecondary In general care areas, each patient bed location shall be provided with a minimum of ___ receptacles. - anseight Which of the following is required to have an alternate source of power automatically restored within 10 seconds after the interruption of the normal source in a nursing home? - ansLighting in dining halls
Which of the following is required to be on the life safety branch of a patient care area. - ansAutomatic doors Which of the following is required to be on the life safety branch circuit? - ansAutomatic doors In patient care areas, all receptacles and all non-current-carrying conductive surfaces of fixed electric equipment operating at over 100 volts that is likely to become energized and is subject to personal contact shall be connected to ___. - ansan insulated copper equipment grounding conductor Which of the following is required to be on the critical branch of a patient care area. - ansNurse call systems Luminaires more than 2.3 m (71/2 ft) above the floor and switches located outside of the patient vicinity ___. - ansare not required to be grounded by an insulated equipment grounding conductor Listing and labeling information included with panelboards and switchboards contains information regarding the correct ___ of the equipment. - ansI. inspection II. mounting When installing panelboards or switchboards, you must follow all manufacturer's installation requirements. - ansTrue NEC® Article 110.16 requires that switchboards, panelboards, and industrial motor control panels in other than dwelling occupancies that are likely to require examination, adjustment, servicing, or maintenance while energized shall be field marked to warn qualified persons of ___. - ansarc flash hazards Unused openings in panelboards can be closed using - anslisted fillers The qualified person must also have knowledge in the selection and proper care and use of ___and other safety equipment and tools. - ansPPE The NEC® and ___ require that all switchboards, panelboards and industrial motor control panels shall be field marked to warn qualified persons of arc flash hazards. - ansNFPA70E A qualified person is one who has ___ of the hazards involved and what precautions must be taken to prevent any personal harm or equipment damage. - ansa. knowledge b. understanding c. training To assure an electrically safe work condition when working on switchboards and panelboards, the power supplying switchboards or panelboards must be turned off and all ___ procedures must be followed. - ansa. lock-out b. tag-out c. deenergizing Generally, flexible cords and cables shall be installed in continuous lengths without splices or taps. - ansTrue The "J" designation in any of the "S-type" flexible cords designates ___. - ansa junior size An electric-discharge luminaire utilizes a ___ for the operation of the lamp. - ansballast ___ is a type of lamp used in an HID luminaire. - ansI. Mercury-vapor III. Nickel cadmium ___ shall not support luminaires weighing over 6 lb. - ansLampholders The NEC® prohibits mounting luminaires directly to a tree. - ansFalse Any branch circuit conductor located within ___" of a ballast, within a ballast compartment, shall have an insulation rating not lower than 90ºC. - ans