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Electrician's Licensing Exam
NEC Article ______ defines breakers and fuses. According to NEC Article 100, a device that opens and closes a circuit by nonautomatic means automatically closes for a predetermined overcurrent. Annex _____ of NEC covers conduit fill. Annex C of NEC covers conduit and tubing fill for conductors and fixture wire fill. NEMA stands for National Electrical Manufacturers Association True - NEMA is the acronym for National Electrical Manufacturers Association. What does it mean when a receptacle has "NEMA 5-20R" on it? A receptacle with NEMA 5-20R on it has an amperes rating of 20, will take a NEMA- 5 - 15P or NEMA- 5 - 20P plug, and has a voltage rating of 125. NEC Tables 310-10 through 310-21 provide information on. The sizes of copper and aluminum wire, as well as the coating of wire that has fewer than three current carrying wires in a cable or conduit or that is buried in the earth. Which NEC tables(s) cover(s) the fill of metal boxes? The fill of metal boxes appears in NEC Tables 314.6 A and B. NEC Article _____ address EMT. NEC Article 358 covers EMT. Which NEC articles cover the installation requirements for RMC, IMC, and EMT? NEC Articles 342, 344, and 358 outline the installation requirements of RMC, IMC, and EMT. IN NEC 2008, what does Table 370.6A cover? Shows in two columns (milimeters and inches), how many wires in trade size you can place in a box. What NEC table would you go to to find trade size of conduit and raceway size? Chapter 9, Table 4 outlines trade size of conduit as well as raceway size. NEC Articles _____ and _____ covers metallic and non-metallic raceways in buildings. NEC Article 386 covers metallic or metal raceway; NEC Article 388 covers PVC pipe. The Panel Board requirements for Application in Construction appear in NEC Article? NEC Article 408 covers panel board applications. The smaller kitchen counter requiring a receptacle is _____ inches. A 12in. counter requires a receptacle because it holds small appliances. What new code is needed for protection in all habitable spaces? According to new codes, ARC fault protection is needed many additional parts of the house. A 12-foot hallway requires one receptacle to meet code. (True or False) True, One is required, Two are suggested. NEC Article 100 is dedicated to? Definitions The main ground on a service is a(n) _____. Ground Rod
What does NEC Section 250-28A require? A main bonding jumper and a system bonding jumper. NEC section 250-28A provides information on what material can be used for a main bonding jumper. (True or False) True A bonding screw is what color? A bonding screw is green. A subpanel requires a bonding screw? (True or False) False, A bonding screw is unneeded in a subpanel. Name the methods of sizing bonding jumpers outlined in NEC Section 250-28D. 1. Bonding jumper is sized not less than 12.5% of the largest phase conductor.
- Based on the largest ungrounded service conductor.
- Based on the largest sum of the service conductors. NEC Table _____ covers grounding electrode conductor sizing. NEC Table 250. Which NEC reference identifies wire sizing and the temperature a wire can handle in amps? NEC Tables Annex C1 and C2 identify both wire sizing and the temperature a wire can handle in amps. Define a grounding system according to NEC. A gounding system is connected to the ground or to a conductive body that extends the ground connection. What is the topic of NEC Section 250-122? Is dedicated to the sizes of the grounding conductor What is the NEC definition of a circuit breaker? A device designed to trip when an overcurrent is detected. NEC Section 300-13 provides information on? Mechanical and Electrical continuity conductors. What is the subject of NEC Section 250-2D? Bonding jumpers ______ are the subject of NEC Section 680-20. Electrical installations at permanently installed pools. Which NEC Section covers equipment grounding conductors. NEC Section 250- 118 Which NEC sections covers identification of equipment grounding conductors? NEC Section 250-119 1- 14 Which NEC Section covers ground terminal identification. NEC Section 250- 126 Bonding is the establishment of ______ connection between metal parts. Reliable NEC Section 250-134 provides information on what topic? Equipment fastened or connection between metal parts. Equipment grounding conductor _____ is (are) discussed in NEC Section 250-130. Connections NEC Section 250-118 states that a grounded conduct must run _____ flexible conduit. inside
Explain the proper way to ground a subpanel in the same building. To ground a subpanel in the same building, run a four-wire system from main panel to subpanel. Discuss the proper way to ground a subpanel in another building. To ground a subpanel in the another building, run bare copper wire from subpanel to ground rod inside or outside. Something that is ______ is connected to ground or to a conductive body that extends the grounding connection. Grounded Describe a grounding conductor. A grounded conductor is a system or circuit that is intentionally grounded. Define the term grounding conductor. A grounding conductor is a conductor or circuit of a wiring system to a grounding electrode (ground rod). A(n) _____ is the fundamental particle of electricity. Electron Voltage can be fatal to a person. (True or False) False, Current is fatal to people not Voltage What determines the severity of an electrical shock? Voltage level, amount of protective clothing, and moisture on skin or outerwear all impact a ground connection. Grounding reduces the voltage that might cause a fatal electrical shock by allowing excess current to flow to the ground. (True or False) True _____ and ______ are two types of electrical faults. Ground and Arc are two types of electrical faults. On a 400-amp services, how many ground rods are required? 2 ground rods 6 ft apart. The standard length for IMC is? Two outside ground wire are needed on a 400 amp. NEC allows electricians to ground gas pipes to existing, grounded water pipes. (True or False) True, when those water pipes are grounded. When is building steel permitted in an electro grounding system? When only the steel is connected to earth ground. _____ determines what size ground wire used on a service. The size of the largest conductor determines what size ground wire used on a service. A grounding conductor is what color? A grounding conductor is green. What is meant by the term isolated grounded reciprocal? An isolated grounded reciprocal is a separate ground from a device directly to a panel. Explain the process of cad welding? Exothermic welding involves the fusion of metal materials or copper to rebar. Electricians may use rebar as a grounding means. (True or False) True, Electricians may use rebar as a grounding means.
Electricians must use a(n) _____ to properly connect number 4 copper to a ground rod. A Direct burial clamp is needed to properly connect number 4 copper to a ground rod. Using NEC Section 250-8, identify five methods of making connections. 1. Listed Pressures Connectors
- Terminal Bars
- Pressure Connectors Listed As Ground and Bonding Equipment
- Exothermic Welding
- Machine screw-type fasteners that engage not less than two threads or are screwed with nuts Underground service is simpler to troubleshoot and repair than overhead service? (True or False) Relative to underground service, overhead electrical service is simpler to troubleshoot and repair and is the easier option when running electricity across roadways, waterways, and right-of-ways. In NEC, Table _____ provides the sizing of grounding electrode conductors. NEC 250.66 provides the sizing of grounding electrode conductors Describe the process for bonding three 200-amp disconnects to make a proper grounding system. To make a proper grounding system using three 200-amp disconnects, use a ground wire of sufficient size to go from panel to panel with a lug, screw, or ground bar, if provided. In terms of AWG, what is the minimum grounding conductor size permitted? The smallest grounding conductor permitted is 6 awg or larger. The way to ground a transformer in a commercial building is to place a grounding rod inside the building? (True or False) False, The way to ground a transformer in a commercial building is to place a grounding rod outside or beneath the building. Why do stoves require a four-wire system? Two hots are needed to operate the stove neutral. The timers and clocks can serve as ground for tripping mechanism. Why do dryers require a four-wire system? Two hots are needed to operate the heater neutral. The timers can serve as ground for tripping mechanism. Air-conditioning units, hot water heaters, and baseboard heat require a four-wire system? (True or False) False, a A/C unit needs only 220 and a ground to complete the circuit. Which of the following NEC sections outlines which air-conditioning systems requires no grounding? NEC 250. Explain where and why isolated systems are used. Isolated systems are used in healthcare facilities due to explosive gases. Electricians should put grounded conductors on yellow reciprocal screws? (True or False) False, grounding conuctors belong on the green screws. On a 200-amp service, the electrician should use _____ or _____ size grounded conductor in the service cable. 2/0 or 4/
NEC Article _____ outlines the restrictions for using plastic junction or device boxes. NEC 314. NEC Chapters 1-4 governs basic practices in effect in hazardous areas, except as modified by specific requirements outlined in NEC Chapter _____. Chapter 5 Name two hazards found in a Class III hazardous environments. 1. Air-borne Particulate
- Sawdust General-purpose enclosures are NEC approved for intrinsically safe apparatuses. (True or False) True, Intrinsically safe areas are safe with out enclosure, but enclosure are required for other protections. Fusing the load side of a transformer sufficiently protects the transformer. (True or False) False, Fuses on the load side do not protect the transformer. Per NEC 450.3, when a transformer is enclosed, install _____ fuses at the transformer's primary. OCPD The NEC defines ampacity as, "the current, in amperes, that a conductor can carry continuously under the conditions of use without exceeding its temperature rating" Where does NEC list the types of insulation material deemed acceptable in wet locations? NEC
Leads to an unused current transformer should be. NEC 110.23 states that, "Unused current transformers associated with potentially energized circuits shall be short circuited." In what sections does NEC outline the requirements for appliance calculations? NEC 220.16 - 220. cover appliance calculations. Typically, transformers are available in one of two types: _____ and _____. Liquid Filled and Dry Versions NEC Chapter 9, Table 5, states, To locate wire type and size to be installed. Repeat for each conductor, keeping a running total. Derate by 40% to ge the total raceway area. NEC Chapter 9, Table 4, states, For a raceway to be used. Find a value for area larger than the raceway area calculated previously. The "3-ft. rule" for clearances around things like control panels is adequate. (True or False) False, Depending on the location and environment, 3ft. may be insufficient clearance. While grouping apparatuses tightly may save space, repair and maneuvering options are limited should a device fail. When establishing ground clearance in new construction. It is best to make the ground clearance slightly more than the NEC-stated requirement to provide a margin for error. (True or False) True, It is a good idea to exceed the requirements by a foot or two. What Section discusses "clearance(s) from ground. NEC 225. Service drops must be installed so as to be "readily accessible." (True or False) False, Per NEC 230.24, Service drop connectors shall not be readily accessible.
Extension cords are acceptable in wet areas. (True or False) True, Per NEC Article 400, only when rated for wet areas. The requirements for liquid-filled transformers are the same regardless of the liquid used in the transformer. (True or False) False, Per NEC 450.23-26 liquid-filled transformers have different requirements based on the dielectric fluid. NEC Article 526 helps electricians determine requirements for _____. Deicing systems Disconnects and switches used with appliances must indicate, on their switches, the on- and off- positions. (True or False) True, Per NEC 422. In a three-phase delta system, the leg with the highest voltage must be _____. Identified as the "B" leg Branch circuits must be loaded equally in terms of wattage per unit area. (True or False) True, Per NEC
An electrician can safely recess a panel board into a flammable wall. (True or False) False, NEC 312.3, disallows recessing panels in flammable walls. All metallic boxes and components must be grounded unless a grounding conductor is absent. (True or False) False, NEC 314.4, requires all metallic boxes to be grounded. Nameplates that rate protective devices describe which of the following? Per NEC 422.11, The size of the breaker to use. NEC maintains no ampacity requirements for fixture wiring because all fixtures undergo the UL approval process. (True or False) False, NEC 402.5 defines ampacity requirements for fixture wires. The calculations for protecting motor circuits are the same as those for non motor circuits. (True or False) False, Protecting a motor and a motor circuit are two very different things Per NEC Article 410, luminaires may mount on drop-ceiling tiles. (True or False) False, ceiling tiles are never appropriate device support. The requirements for burying 240V conductors are found in NEC _____. NEC 300.5, provides requirements up to 600V NEC _____ outlines the requirements fo AC type (armored) cable. NEC 320 A garage door opener is considered an appliance for NEC purpose. (True or False) True, Per NEC
Appliances with motors over 0.125 hp must have a separate means of disconnect. (True or False) True, Per NEC 422. When running new work over old, hanging a second support from a primary support is acceptable practice. (True or False) True, Per NEC 300.11 hanging a second support when running new over old is acceptable and a common practice.
NEC defines "Bonding" as, "The permanent joining of metallic parts to form an electrically conductive path that ensures electrical continuity and the capacity to conduct safely any current likely to be imposed." NEC Table 250.66 applies to the derived conductors of separately derived AC systems. (True or False) True A ground ring encircling a building or structure, in direct with the earth consisting of at least _____ft. of bare copper not smaller than _____ AWG, shall be permitted as an electrode. 20ft. of bare copper not smaller than 2 AWG Where a main bonding jumper or a system bonding jumper is a screw only, the screw shall be identified with a _____ finish that shall be visible with the screw installed. Green finish NEC Table 220.42 can be used to calculate lighting loads in a restaurant dining area. (True or False) False, demand factors of lighting does not apply to this table. Outdoor lighting installations exceeding _____ are subject to the clearance requirements outlined in NEC 225.7 120V Open conductors belonging to separate circuits must be separated by? Per NEC 225.14, separated by 4in. NEC requires a panelboard circuit directory. (True or False) True, although there are exceptions. A tree over 50 ft. high may be used as an overhead service support for a single-story residence only. (True or False) Per NEC 230.10, vegetation is disallowed as a support device. What is the maximum number of sets of service conductors a service drop or lateral may supply? Per NEC 230.40, "Every service drop or lateral shall supply only one set of service entrance conductors." ampacity The maximum amount of electrical current a conductor or device can carry before sustaining immediate or progressive deterioration. ampere Is a measure of the amount of electric charge passing a point in an electric circuit per unit time. In electric circuits, a load usually converts electrical energy to _____, _____, or _____. Heat, Magnetism, and Light A circuit has a source of 10V and a resistance of 2hm. A fuse in this circuit should have what value? Using ohms law, the fuse value would be 10V/2ohms or 5 amperes. However, if the voltage increased slightly and harmlessly, the fuse would blow. Therefore the fuse should be based on the nature of the load. In electrical work, electrons are always balanced between two points. (True or False) False, The term electricity is defined as the imbalance in the negative charges, or electrons, between two points. Differentiate between AC and DC. In DC, electrons flow in one direction only. In AC, electrons "saw" back and forth in the load. AC is easier to manufacture and is most often delivered and used in a residence, business, or factory.
Which of the following is not a conductor? Gold, Silver, Copper Water, Air. Air, does not conduct electricity. Current is measured in _____. amperes, named after the French scientist, Andre Marie Ampere Insulators like air, paper or rubber prevent arcing. (True or False) False, Arcing is the phenomenon in which electrons jump across insulators to positive terminals, which can occur through air, paper, rubber, or any other insulator. A circuit using 2 amps of current with 12V applied dissipates how much current? Given that power equals voltage times resistance, power in this example is 24 watts (2amp x 12V) All electrical equipment and supplies should be considered _____ until determined otherwise. active or live Voltages of _____ or more are considered high. 120V A voltage of 1V applied across a 1ohm resistance produces a 1amp current. If the voltage is doubled and the resistance is halved, the current does what? The current stays the same cause the doubling is offset by the halving. All voltages in a circuit are referenced to Earth ground via a black wire. (True or False) False, via a green wire Define a parallel circuit? In a parallel circuit, each load is connected in a separate path. In a circuit schematic, the branch lines are parallel. The most important aspect of becoming an electrician is learning about _____. Safety is the most important aspect of an electrician's job. A transformer has a voltage ratio of 8:1 and an input of 120V. What is the output Voltage? 15v 120V/ When an ammeter is connected in parallel with a load, ______. Damage may occur in the meter and or personal injury. Motors and generators work the same way. (True or False) True, motors convert electricity to rotational motion, while generators convert rotary motion to electricity. The organization that sponsors the NEC, is the _____. The National Fire Protection Association (NFPA) sponsors the NEC The negative terminal of a battery has a surplus of protons.(True or False) False, The negative terminal has a surplus of electrons and the positive terminal has a surplus of protons Which of the following lacks insulation properties? Rubber, Air, Water, Mica, Paper Water, lacks insulation qualities because it conducts electricity. As a result, it is one of the most hazardous substances in an electrical environment. Current always flows from negative to positive. (True or False) True
According to good engineering practice, a sump pump requires a dedicated circuit. True, like a refrigerator the appliance should continue running when another component fails, the grounding system must be able to support the service on its own. How many cubic inches does each wire take for: 14 gauge ________. 12 gauge ________. 10 gauge ________. 14 gauge; 2 12 gauge; 2. 10 gauge; 3 What factor determines circuit size? Breaker Rating determines ampacity, or size, of a circuit. What is an outlet? According to the NEC, an outlet is defined as a point in a circuit at which current is taken. What are NEC requirements for a receptacle on a peninsula? Receptacles must be installed on a peninsula when the peninsula's long edge is at least 24in. and its short edge is at least 12in. What is the approach for determining the number of receptacles on a 20-amp circuit? First determine whether the application is residential. For residential applications, the NEC provides no guidance. The answer for nonresidential applications is based on box fill. For these applications, most electricians calculate between 1 and 1.5 amperes per receptacle. A whirlpool tub requires GFCI protection. (True or False) Per NEC 680.90(A), GFCI protection Must reside on whirlpool tubs. What three areas of a residence require 20-amp circuits? Three residential areas that require 20- amp circuits are the kitchen, bathroom, and laundry room. A 10 AWG wire carries how many amps? (What size breaker?) 30amps (10 x 3) In front of a panel from floor to ceiling, how much clearance depth is needed? NEC requires a clearance width of 30in. and a clearance depth of 36in. Is a receptacle needed close to an air-conditioning unit? If so, how close must it be? Yes, a receptacle is required in close proximity to an air-conditioning unit. At most, it must be 25ft. distant. An attic with a furnace requires a receptacle. (True or False) True, An attic with a furnace requires a receptacle to honor safety and sound wiring requirements.
A _____-amp breaker goes on a 12 AWG wire. Although a 15amp breaker is above code, it is preferable when considering expansion. Along a wall space, a first outlet should be no more than _____ feet from a door. 6ft A metal fence should be attached to a ground rod? Per NEC 250.116 ground rods should attach to metal fences It is proper procedure to install an exhaust fan and light in a shower area. (True or False) False, unless it is 8ft above the rim of the shower zone and listed for wet environments. Name some tools for installing ground rods. sledge hammer, hammer drill, and ground rod pounders A receptacle should be how high off the floor? 16 in. A switch should be _____ high off the floor? 48 in. A lighting circuit in more than one room is acceptable electrical practice. (True or False) True All new wiring receptacles must be grounded to a neutral bar in the panel box. (True or False) True, Receptacles fed from subpanels must have their equipment grounding bar that is electrically isolated from the neutral bar. What is meant by the phrase shall be? A mandatory act or condition Identify four parties who should be satisfied with the electrical work in a new residence. 1. The Builder
- Homeowner
- Inspector
- Boss Why is M/C cable required in a cupboard instead of Romex? It guards wire against damage.
