Last Minute.txt

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Last Minute.txt
2013-11-13 10:16:41
lightning review

last minute review
Show Answers:

  1. What is the AWG size of Class I Copper Cable?
    17 AWG
  2. What is the AWG size of Class II Copper Cable?
    15 AWG
  3. What is the weight per length of copper Class I cable?
    187.5 lbs/ 1000 feet
  4. What is the weight per length of copper Class II cable?
    375 lbs / 1000 feet
  5. What is the AWG size of Class I aluminium cable?
    14 AWG
  6. What is the AWG size of Class II aluminium cable?
    13 AWG
  7. What is the weight per length of aluminum Class I cable?
    95 lbs/1000 feet
  8. What is the weight per length of aluminium Class II cable?
    190 lbs/1000 feet
  9. What is the diameter of a Class I copper solid air terminal?
    3/8 inch
  10. What is the diameter of a Class II copper solid air terminal?
    1/2 inch
  11. What is the diameter of Class I aluminium solid air terminal?
    1/2 inch
  12. What is the diameter of Class II aluminium solid air terminal?
    5/8 inch
  13. What is the diameter of copper and aluminium tubular air terminal?
    5/8 inch

    • AND
    • Copper wall thickness is 0.32 inch
    • Aluminium wall thickness is 0.64 inch
  14. What class can tubular air terminals be used for?
    Class I
  15. What is the coarse and fine thread count of a 1/4" bolt?
    20 and 28
  16. What is the coarse and fine thread count for a 1/2" bolt?
    13 and 20
  17. What is the equation for slope?
    Rise / Run
  18. What year was the Lightning Protection Institute founded in?
  19. The Lightning Protection Institute promotes what?
    • Education
    • Awareness
    • Safety
  20. What are the three standards in the United States for lightning protection?
    • NFPA 780
    • UL 96(A)
    • LPI 175
  21. What five elements need to be in place provide an effective lightning protection system?
    • Strike termination devices
    • Cable conductors
    • Grounding electrode system
    • Bonding
    • Surge Protection Devices
  22. What do lightning protection component materials need to be?
    • Resistant to corrosion
    • Protected from accelerated deterioration
  23. What is electrically charged around us?
    the atmosphere
  24. What proper resistance is expected of a proper grounding electrode if the soil is of normal restivity?
    less than 50 ohms
  25. Copper components installed with 24 inches of a top of a chimney or vent that emits corrosive gases shall be what?
    protected by lead or tin coating
  26. Aluminum conductor shall not be attached or installed in what three circumstances?
    • alkaline-base paint
    • embedded in concrete/masonry
    • subjec to excessive moisture
  27. Connector fitting shall be used at what three splices?
    • End-to-end
    • Tee
    • Y
  28. What amount of lbs shall all fittings be able to withstand in a pull test?
    200 lbs
  29. Which Class can crimp type connectors be used in?
    Class I only.
  30. What is the minimum outside diameter of masonry anchors?
  31. How far above the object shall air terminals extend to protect the object?
    no less than 10"
  32. What is the wind resistance area of an ornament or decoration?
     no greater than 20 square inches
  33. What span and slope can a pitched roof have?
    • A span of 40 ft or less and a slope of 1/8 or greater  OR
    • a span of 40 ft or more and a slope of 1/4 or greater
  34. What is the horizontal protected distance formula?
  35. What happens to the zone of protection when the protection is no higher than 25 feet above grade?
    1 to 2
  36. What happens to the zone of protection when the protection is higher than 25 feet but lower than 50 feet?
    1 to 1
  37. How many feet above grade is it required to protect down conductors from mechanical damage?
  38. How many feet above grade is it required to protect down conductors that are entering into corrosive soil?
    3 feet
  39. What is the minimum diameter and length of ground rods?
    1/2" and 8 ft long
  40. How far shall ground rods extend vertically?
    not less than 10'
  41. What is the separation between any two ground rods?
    at least the sum of the rod lengths
  42. What is the bonding distance formula?
  43. All grounded media and buried metallic conductors that can assist in providing a path for lightning currents in or on a structure shall be interconnected to the system within how many feet of the base of the structure?
    12 feet
  44. What are the three different situations for grounding in shallow top soil?
    • Soil a minimum of 18 inches - ground ring/radial/ plate
    • Soil less then 18 inches deep - ground ring/radials/plates
    • No soil (solid rock) - conductor can be laid directly on bed rock extending a minimum distance of 2 feet from the foundation (ground plate termination)
  45. For structures exceeding 60 feet in height, what shall the interconnection of lightning protection grounding electrodes and other grouneded media be in the form of?
    a ground loop conductor
  46. What standards does it require that buildings over 60 feet in height require a ground loop?
    LPI 175 and NFPA 780
  47. What does the interconnection of building system ground devices include?
    • Lightning protection
    • Electric service
    • Communications
    • Antenna system grounding
  48. Within how many feet is it required to bond underground metallic piping systems (water, gas, conduits, petroleum) of a structure?
    25 feet
  49. What is the common bonding point if the grounded systems (water, gas, electric, communications) are interconnected at a common accessible point in the structure?
    • A ground bar
    • A section of water pepe OR
    • The metallic structural frame
  50. Metal bodies located outside or inside the structure that contribute to lightning hazards shall be what?
    interconnected with the lightning protection system
  51. Do metal bodies grounded automattically through the structural connection (steel frame) need additional bonding?
  52. What is potential equalization?
    the bonding together of grounded systems at different building height intervals to eliminate side flash
  53. Structures exceeding 60 feet in height need what three potential equalizations?
    • Ground-Level
    • Roof-Level (12 feet)
    • Intermediate-Level
  54. Structures up to 60 feet in heigh need what two potential equalizations?
    • Ground-level
    • Roof-level  (7 feet)
  55. Grounded metal bodies need to be bonded if they fall within what?
    the calculated bonding distance
  56. How small can ground loop conductors be?
    no smaller than main lightning conductor
  57. Should SPDs be grounded through a lightning protection down conductor?
  58. Where are SPDs installed?
    All power service entrances
  59. What dp SPDs need to be in compliance with?
    UL 1449 Edition 3
  60. What is the nominal discharge rating of SPDs for branch panels or subpanels?  AND is for signal data or communication systems?
  61. What is the nominal discharge rating of SPDS for supplementary protection?
  62. What is the nominal discharge rating of SPDS for service entrances?
  63. Gable
  64. Broken Gable
  65. Gambrel
  66. Hip
  67. What shall surge protection be provided for?
    • Conductive signal
    • data
    • communication lines
  68. What three things should be considered when selecting SPDs?
    • frequency
    • bandwidth
    • voltage
  69. What shall SPDs for data and signal line protection have?
    common mode protection
  70. When installing strike termination devices on structural steel what are the intervals?
    air terminals are connected to the metal framework at intervals not exceeding an average distance of 100 feet and are to be as widely spaced as possible.
  71. When fastening conductor to a metallic column what is the diameter and how many threads need to be fully engaged?
    • no less than 1/2 inch in diameter
    • at least 5 threads fully engaged
  72. When installing ground electrodes that are connected to metallic columns, how are they installed?
    around the perimeter of the structure at intervals averaging not more than 60 feet apart.
  73. What is a low resistance continuous metallic path designed for the purpose of transferring lightning from the top of a structure into the earth?
    lightning protection system
  74. What can be used for protecting down conductors from mechanical damage?
    • wood
    • plastic (PVC)
    • metal laid over the conductor
  75. When does the zone of protection arc change to 100 feet?
    • Flammable materials
    • Ammunition
    • Masts (2 or more)
  76. How far away do silos and storage tanks have to be to be classified as standing alone?
    6 feet
  77. What determines an adjacent storage structure?
    if it is 6 feet or less away from the main building but not attached
  78. How tall is a heavy duty stack and what is the single cross-sectional flue area?
    • more than 75 feet
    • flue area exceeds 500 square inches
  79. What class materials should heavy duty stacks have?
    Class II
  80. The upper 25 feet of a heavy duty stack shall have what?
    a continuous covering of lead
  81. Can you used aluminum material on heavy duty stacks?
  82. What are the intervals of air termainls on the rim  of stacks?
    not exceeding 8 feet
  83. How far shall air terminals extend above the heavy duty stack?
    > 18 inches <30 inches
  84. On heavy duty stacks how far above earth are down conductors to be protected from damage?
    At least 8 feet
  85. If ground rods are used for a heavy duty stack what is the diameter and length?
    5/8 inch and 10 feet long
  86. How far away does a metal water pipe system have to be to be bonded with the LPS of a stack?
    within 25'
  87. How far away do trunks of trees have to be from a structure to provide lightning protection?
    within 10 feet
  88. What are the three design concerns as it relates to open shelters?
    • Step potential
    • Touch potential
    • Sideflash (to person/animal)
  89. Should aluminum materials be used on trees?
  90. When protecting an open structure how many down conductors should there be?
    a down conductor for every corner
  91. How shall clamps be secured to ground rods and down conductors?
    • Make contact for 1 1/2 inches
    • Secured with at least two bolts
  92. When should connections to ground electrodes be made?
    • Not less than 1 foot below grade
    • Not less than 2 feet away from the foundation wall
  93. How far shall ground rods be extended vertically?
    not less than 10 feet
  94. What are the three things ground rods can be made of?
    • Cooper-clad steel
    • Solid Copper
    • Stainless Steel (corrosive)
  95. Masonry anchors are
    1/4" diameter
  96. What type of metal body must always be considered for bonding?
    non-isolated metal body
  97. How thick must metal be to be used as an air terminal or main cable conductor?
    At least 3/16" thick
  98. What is the minimum thickness and surface area of a ground plate?
    0.032 inches thick and 2 square feet
  99. What are the three approved materials for lightning protection?
    • Copper
    • Copper Alloys
    • Aluminum