Article 225: Outside Branch Circuits And Feeders

Transcription

1 Part C: Code Book Questions Article 225: Outside Branch Circuits And Feeders 1.! Open (individual) aerial overhead conductors shall be insulated or covered when within! feet of a building.! (a) 10! (c) 15! (b) 12! (d) 25 2.! Conductors for festoon lighting shall be of the type, unless supported by messenger wires.! (a) thermoplastic! (c) #12 or larger! (b) rubber covered! (d) all of these 3.! What is the minimum size conductor (AWG) that may be used for an overhead feeder which is 35! feet in length from a residence to a remote garage?! (a) #10 copper! (c) #6 copper! (b) #8 copper! (d) #4 copper 4.! Messenger wires used to support festoon wiring shall not be attached to any.! (a) downspout! (c) plumbing equipment! (b) fire escape! (d) all of these 5.! Running open wiring on insulators, MI or MC cable, messenger-supported wiring, conductors in! raceway, and other approved means on the outdoor building surfaces is permitted for circuits! operating at a maximum of volts nominal.! (a) 600! (c) 1000! (b) 750! (d) ! Open conductors shall be supported on glass, porcelain-knobs, or.! (a) racks! (c) strain insulators! (b) brackets! (d) all of these 7.! Conductors on poles shall have a separation of not less than feet where not placed on racks! or brackets.! (a) 1! (c) 2! (b) 1-1/2! (d) 2-1/2

2 8.! For open conductors of not over 600 volts, clearance from ground shall be feet, above! finished grade where the supply conductors have a nominal voltage limited to 150 volts to ground! and accessible to pedestrians only.! (a) 8! (c) 12! (b) 10! (d) 15 9.! Distances from signs, radio, and TV antennas, tanks or other non-building or non-bridge! structures, clearances, vertical, diagonal and horizontal, shall not be less than feet.! (a) 2! (c) 6! (b) 3! (d) 8 10.!Where buildings exceed 3 stories or 50 feet in height, overhead lines shall be arranged, where! practicable, so that a clear space (or zone) of at least feet wide will be left either adjacent to! the buildings or beginning not over 8 feet from them to facilitate the raising of ladders when! necessary for fire fighting.! (a) 4! (c) 8! (b) 6! (d) !Raceways on the exterior of buildings shall be in wet locations.! (a) watertight and arranged to drain!! (c) arranged to drain and raintight! (b) weatherproof and covered!! (d) rainproof and guarded 12.!Where outdoor lampholders, attached to pendants, have terminals that puncture the insulation! and make contact with the conductors they shall be attached only to.! (a) conductors with rubber insulation!! (c) conductors of the stranded type! (b) solid conductors!! (d) a #12 conductor 13.!Locations of lamps for outdoor lighting shall be generally below.! (a) all energized conductors! (c) electric utilization equipment! (b) transformers! (d) all of these 14.!Vegetation such as trees shall not be used for support of.! (a) lighting fixtures! (c) overhead conductor spans! (b) brackets or clamps! (d) all of these

3 15.!In general, each building, or set of buildings on a single property shall be supplied by only one set! of feeder or branch circuit conductors?! (a) one! (c) three! (b) two! (d) three or more Article 230: Services 16.!Service conductors supplying a building or other structure pass through the interior of! another building or structure.! (a) shall! (c) may! (b) shall not! (d) may not 17.!Conductors shall be considered outside a building.! (a) where installed beneath a building in conduit under at least 18 of earth! (b) where installed beneath a building incased in concrete, or brick, at least 2 thick! (c) where installed within a building incased in concrete, or brick, at least 2 thick! (d) all of these 18.!Conductors other than service conductors shall not be installed in the same service raceway or! service cable except.! (a) grounding conductors! (c) load management control conductors! (b) bonding conductors! (d) all of these 19.!Service conductors run above the top level of a window shall be permitted to be less than the! foot requirement.! (a) 3! (c) 8! (b) 6! (d) !Overhead service-drop conductors run individually shall be.! (a) insulated! (c) bare (for grounded multiconductor cables)! (b) covered! (d) all of these 21.!Overhead service-drop conductors shall have.! (a) adequate mechanical strength! (b) sufficient ampacity to carry the load! (c) computed in accordance with Article 220! (d) all of the above

4 22.!Overhead service-drop conductors supplying only limited loads of a single branch circuit shall not! be smaller than copper.! (a) #8! (c) #12! (b) #10! (d) #14 23.!What is the minimum height of a service drop attachment to a building?! (a) 8 feet! (c) 12 feet! (b) 10 feet! (d) 15 feet 24.!A service drop over a residential driveway shall have a minimum height of feet.! (a) 10! (c) 15! (b) 12! (d) !The minimum clearance for service drops over commercial areas subject to truck traffic is! feet.! (a) 10! (c) 15! (b) 12! (d) !Where a service mast is used for the support of service drop conductors it shall be of adequate! strength or be supported by.! (a) studs! (c) rigid conduit! (b) braces or guys! (d) R.C. beams 27.!Where raceway-type service masts are used all raceway fittings shall be for use with service! masts.! (a) identified! (c) heavy-duty! (b) approved! (d) none of these 28.!A uninsulated copper grounded conductor can be used in an underground service.! (a) where used in a raceway! (b) directly buried where judged suitable for soil conditions! (c) directly buried where part of cable assembly identified for underground use! (d) all of the above 29.!Underground service conductors must have a rating not smaller than AWG.! (a) #3 aluminum! (c) #6 copper! (b) #4 aluminum! (d) #8 copper

5 30.!Buildings of multiple occupancy shall be permitted to have set of service-entrance! conductors for each service of different characteristics run to each occupancy or group of! occupancies.! (a) one! (c) two or more! (b) two! (d) no 31.!Service entrance cables where subject to physical damage shall be protected in.! (a) EMT! (c) Rigid Metal Conduit! (b) IMC! (d) all of these 32.!Service cables mounted in contact with a building shall be supported at intervals not exceeding! feet.! (a) 2-1/2! (c) 4-1/2! (b) 3! (d) !Open individual service conductors in wet locations, maximum 600 volts, supported every!9 feet! should have a minimum clearance between conductors of.! (a) 2-1/2! (c) 6! (b) 3! (d) !Service heads for service conductors shall be.! (a) raintight! (c) rainproof! (b) weatherproof! (d) watertight 35.!Where it is impracticable to locate the service head above the point of attachment the service head! location shall be permitted no further than feet from the point of attachment?! (a) 1! (c) 3! (b) 2! (d) 4 36.!To prevent the entrance of service-entrance conductors shall be connected to the service-! drop conductors (1) below the level of the termination of the service head, or (2) below the level of! the service head.! (a) air! (b) dirt! (c) dust! (d) moisture 37.!The Code has assigned the color to the high-leg of a 4-wire delta connected secondary.! (a) black! (c) orange! (b) red with green tracer! (d) pango pink

6 38.!Which of the following is not considered service equipment:! (a) meter socket enclosure! (c) panelboard! (b) service disconnecting means! (d) all of these 39.!The service disconnecting means shall be installed at a readily accessible location either outside of! a building or structure, or of the service conductors.! (a) inside nearest the point of entrance!! (c) inside within 8 feet! (b) in an inside bathroom!! (d) nearest the point of entrance 40.!Two or three single-pole switches or breakers, capable of individual operation, shall be permitted! on multiwire circuits, one pole for each ungrounded conductor, as one multipole disconnect,! provided they are equipped with handle ties, or a master handle to disconnect all conductors of! the service with no more than operations of the hand.! (a) one! (c) four! (b) two! (d) six 41.!Each service disconnecting means shall disconnect all ungrounded service conductors from! the premises wiring system.! (a) automatically! (c) simultaneously! (b) independently! (d) separately 42.!The service disconnecting means shall plainly indicate.! (a) its voltage rating! (c) the maximum fuse size! (b) the maximum horsepower rating! (d) whether it is in the open or closed position 43.!For an installation consisting of not more than two 2-wire branch circuits, the service! disconnecting means shall have a rating of not less than amperes.! (a) 20! (c) 60! (b) 30! (d) !For a one-family dwelling, the service disconnecting means shall have a rating of not less than! amps, 3-wire.! (a) 15! (c) 60! (b) 30! (d) 100

7 45.!The service conductors shall be connected to the service disconnecting means by or other! approved means.! (a) pressure connectors! (c) other approved means! (b) clamps! (d) all of these 46.! may be connected to the supply side of service disconnect.! (a) Meters! (c) Solar photovoltaic systems! (b) Current-limiting devices! (d) all of these 47.!Where the service overcurrent devices are locked or sealed, or otherwise not readily accessible,! branch-circuit overcurrent devices shall be.! (a) of lower ampere rating than the service overcurrent device! (b) mounted in an readily accessible location! (c) installed on the load side! (d) all of these 48.!Where necessary to prevent, an automatic overcurrent device protecting service conductors! supplying only a specific load, such as a water heater, shall be permitted to be locked or sealed! where located so as to be accessible.! (a) tripping! (c) heat build up! (b) corrosion! (d) tampering 49.!Ground-fault protection of equipment shall be provided for solidly grounded wye electrical! services of more than 150 volts to ground, but not exceeding 600 volts phase-to-phase, for each! service disconnecting means rated amperes or more.! (a) 200! (c) 800! (b) 600! (d) !The maximum setting of the ground-fault protection for a service disconnect shall be 1200! amperes, the maximum time delay shall be for ground-fault currents equal to or greater than! 3000 amperes.! (a) 1/2 second! (c) 3 seconds! (b) 1 second! (d) 100 milliseconds 51.!The ground fault protection system shall be performance tested when it is.! (a) first installed! (c) inspected! (b) energized for the first time! (d) manufactured

8 52.!Ground-fault protection that functions to open the service disconnect protection from faults! on the line side of the protective element.! (a) affords! (c) serves as! (b) affords no! (d) gives adequate 53.!Service conductors on a 600 volt system shall not be smaller than unless in multiconductor! cable.! (a) #6! (c) #2! (b) #4! (d) #1 54.!Isolating switches, over 600 volts, shall be provided with a means for readily connecting the load! side conductors to ground when disconnected from the.! (a) current! (c) service cable! (b) equipment! (d) source of supply 55.!A circuit breaker with a trip setting of not more than times the ampacity of the conductors,! shall be considered as providing the required short-circuit protection.! (a) 3 times! (c) 6 times! (b) 5 times! (d) 8 times Article 240: Overcurrent Protection 56.!Conductor overload protection is not required if.! (a) the conductors are oversized by 125%! (b) the conductors are part of a limited-energy circuit! (c) interruption of the circuit can create a hazard! (d) short circuit protection is provided 57.!If the allowable current carrying capacity of a conductor does not correspond to the rating of a! standard size overcurrent device, the next larger size may be used provided the current does not! exceed amps.! (a) 200! (c) 800! (b) 500! (d) !A #16 fixture wire is considered protected by a 20 amp overcurrent device up to feet.! (a) 25! (c) 75! (b) 50! (d) 100

9 59.!Field assembled flexible cords shall be considered as protected by a 20 amp branch circuit breaker! if it is.! (a) not less than 6 in length! (c) #18 AWG or larger! (b) #20 AWG or larger! (d) #16 AWG or larger 60.!Which of the following is not a standard size fuse?! (b) 601 amp! (a) 110 amp! (d) 125 amp! (c) 75 amp 61.!Which of the following is a standard size fuse?! (a) 75! (c) 601! (b) 95! (d) !The rating of an adjustable trip circuit breaker having means for adjusting the current setting! (long-time pickup setting) shall be the maximum setting possible.! (a) external! (c) readily accessible external! (b) an isolated! (d) accessible 63.!Fuses, circuit breakers, or combinations thereof, shall not be connected in parallel except.! (a) field installed! (b) readily accessible! (c) factory-assembled in parallel, and listed as a unit! (d) all of these 64.!Supplementary overcurrent devices shall.! (a) not be required to be readily accessible! (b) be used as a substitute for branch-circuit overcurrent devices! (c) be readily accessible! (d) rated not over 15 amp 65.!A fuse or an overcurrent trip unit of a circuit breaker shall be connected in series with! each.! (a) ungrounded conductor! (c) overcurrent device!! (b) grounded conductor! (d) transformer

10 66.! devices that provide equivalent overcurrent protection in closed-loop power distribution! systems shall be permitted as a substitute for fuses or circuit breakers.! (a) Approved! (c) Accessible! (b) Listed! (d) Automatic 67.!A feeder tap in a raceway terminating in a single circuit breaker with an ampacity 1/3 of the! feeder conductors may extend not over feet.! (a) 6! (c) 25! (b) 10! (d) !Where a change occurs in the size of the ungrounded conductor, a similar change shall be! permitted in the size of the conductor.! (a) hot! (c) grounded! (b) grounding! (d) none of these 69.!In dwelling units and guest rooms of hotels and motels overcurrent devices shall not be located! in.! (a) bathrooms! (c) were exposed to physical damage! (b) clothes closets! (d) all of these 70.!Overcurrent devices shall be enclosed in.! (a) cabinets! (c) equipment assemblies! (b) cutout boxes! (d) all of the above 71.!Enclosures for overcurrent devices in damp or wet locations shall be identified for use in such! locations and shall be mounted so there is at least inch air space between the enclosure and! the wall.! (a) 1/4! (c) 3/4! (b) 3/8! (d) 1 72.!Fuses and circuit breakers shall be so located or that persons will not be burned or! otherwise injured by their operation.! (a) concealed! (c) shielded! (b) guarded! (d) elevated

11 73.!Handles or levers of circuit breakers and similar parts which may move suddenly in such a way! that persons in the vicinity are likely to be injured by being struck by them shall be.! (a) concealed! (c) isolated! (b) labeled! (d) all of these 74.!Plug fuses and fuseholders can be used in circuits supplied by a system having a grounded! neutral where the line-to-neutral voltage does not exceed volts.! (a) 150! (c) 115! (b) 125! (d) !Plug fuses of 15-ampere and lower rating shall be identified by a configuration.! (a) octagonal! (c) hexagonal! (b) square! (d) round 76.!The maximum rating of an Edison-Base plug fuse is amperes, and shall be used only as a! replacement item in existing installations.! (a) 20! (c) 60! (b) 30! (d) !Fuses shall be plainly marked with.! (a) ampere rating! (c) interrupting rating where other than 10,000 amps! (b) voltage rating! (d) all of these 78.!A circuit breaker shall be of such design that any alteration of its will require dismantling of! the device or breaking of a seal for other than intended adjustments.! (a) trip point! (c) calibration! (b) time required for its operation! (d) all of these 79.!Every circuit breaker having an interrupting rating other than amperes, shall have its! interrupting rating shown on the circuit breaker.! (a) 1000! (c) 5000! (b) 2000! (d) !Where used as switches in 120 volt and 277 volt fluorescent lighting circuits, circuit breakers shall! be listed and shall be marked.! (a) SWD! (c) ULD! (b) UL! (d) any of these

12 81.!A two pole circuit breaker that may be used for protecting a 3-phase corner grounded delta circuit! if it is marked to indicate such suitability.! (a) 1Ø, 120/240v! (c) 1Ø/2Ø/3Ø! (b) 1Ø - 3Ø! (d) 480Y/277v 82.!The protective devices(s) shall be capable of detecting and interrupting all values of current which! can occur at their location in excess of their trip setting or.! (a) boiling point! (c) capacity! (b) melting point! (d) all of these 83.!The long-time trip element setting of a breaker or the minimum trip setting of an electronically! actuated fuse shall not exceed times, the ampacity of the conductor.! (a) 3! (c) 6! (b) 4! (d) 8