NCCER Elc L1/M6 MIX

NCCER
1.0x

NCCER Elc L1/M6 MIX

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Tags: NCCER
  1. Objectives

    Slide 2 - Objectives

    • When trainees have completed this session, they should be able to do the following:
    • 1. Describe the different types of nonmetallic and metallic boxes.
    • 2. Calculate the NEC® fill requirements for boxes under 100 cubic inches.
    • 3. Identify the appropriate box type and size for a given application.
    • 4. Select and demonstrate the appropriate method for mounting a given box.  
    • Device Boxes 26106-14
  2. Performance Tasks

    Slide 3 - Performance Tasks

    • 1. Identify the appropriate box type and size for a given application.
    • 2. Select the minimum size pull or junction box for the following applications:
    • • Conduit entering and exiting for a straight pull.
    • • Conduit entering and exiting at an angle.
    • Device Boxes 26106-14
  3. 1.0.0

    Slide 4 - 1.0.0

    • Device Boxes 26106-14
    • Introduction
    • • Boxes must be properly selected for the application, and then sized and installed correctly in order to minimize costs and ensure safety.
    • • All openings in outlet boxes must be closed per NEC Section 314.17(A).
  4. 2.0.0

    Slide 5 - 2.0.0

    • Device Boxes 26106-14
    • Types of Boxes
    • • Boxes are typically constructed of steel; other metals, such as cast iron, aluminum, or brass; or nonmetallic materials, such as fiberglass-reinforced polyester.
    • • Boxes are designed for various uses, such as in floors, walls, and ceilings. Ceiling boxes must be attached to a structural member of the building and must be rated for the weight of the attached fixture.
  5. 2.1.0

    Slide 6 - 2.1.0

    • Device Boxes 26106-14
    • Octagon and Round Boxes
    • • Octagon and round boxes are used for wall-mounting lighting fixtures (luminaires).
    • • Extension rings are used where necessary to add to capacity or bring the box flush with the finished surface.
  6. 2.1.0

    Slide 7 - 2.1.0

    • Device Boxes 26106-14
    • Nonmetallic Round Box and Fixture Ring with Bar Hanger
    • Fixture hangers are used to support a fixture between two ceiling joists.
  7. 2.1.0

    Slide 8 - 2.1.0

    • Device Boxes 26106-14
    • Shallow Round Box Used for Mounting a Lighting Fixture
    • • Some fixtures include a wire termination space and can be used with shallow ceiling boxes supported by a joist.
    • • The NEC® requires that boxes have a minimum depth based on the size of the conductors contained in the box.
  8. 2.2.0

    Slide 9 - 2.2.0

    • Device Boxes 26106-14
    • Square Boxes
    • • Square boxes are available in various sizes and depths. Extension rings can be used to increase capacity.
    • • Square boxes may be screwed/nailed directly to structural members or attached using brackets.
  9. 2.3.0

    Slide 10 - 2.3.0

    • Device Boxes 26106-14
    • Device Boxes
    • • Device boxes are used for flush-mounted applications in residential and light commercial construction.
    • • Some boxes include integral nails for rapid installation.
  10. 2.4.0 – 2.5.0

    Slide 11 - 2.4.0 – 2.5.0

    • Device Boxes 26106-14
    • Masonry Boxes; Boxes for Damp and Wet Locations
    • • Masonry boxes are attached to the rebar before a slab is poured. To avoid offsets, use a tall enough box so that the knockouts are located above the rebar.
    • • Boxes used in concrete or underground applications require the use of weatherproof equipment.
    • Performance Task
    • Identify the appropriate box type and size for a given application.
    • This session will conclude with trainees practicing identifying the appropriate type of box for a given application.
    • Next Session…
    • Sizing Outlet Boxes
  11. 3.0.0

    Slide 12 - 3.0.0

    • Device Boxes 26106-14
    • Sizing Outlet Boxes
    • • The maximum number of conductors permitted in standard outlet boxes is listed in NEC Table 314.16(A).
    • • Devices that add to box capacity include device covers and extension rings.
  12. 3.0.0

    Slide 13 - 3.0.0

    • Device Boxes 26106-14
    • Devices and Components That Require Deductions in Outlet Box Capacity
    • • Deductions must be made for fixture studs, hickeys, cable clamps, switches, receptacles, and conductors.
    • • One conductor is deducted for each fitting and any number of ground wires. Two conductors are deducted for each yoke-mounted device (receptacle or switch).
  13. 3.0.0

    Slide 14 - 3.0.0

    • Device Boxes 26106-14
    • Items That May be Disregarded When Calculating Outlet Box Capacity
    • • Items disregarded when calculating box capacity include grounding clips and screws, wire nuts, cable connectors, prewired fixture wires, and pigtails.
    • • To determine the size of an outlet box, count the number of conductors and equivalents, then determine the space required for each conductor using NEC Table 314.16(B) and multiply that by the equivalent number.
    • • Use NEC Table 314.16(A) to find the correct box size.
  14. 4.0.0 – 4.1.0

    Slide 15 - 4.0.0 – 4.1.0

    • Device Boxes 26106-14
    • Pull and Junction Boxes
    • • Pull and junction boxes must provide enough space in which to install the conductors.
    • • For conductors No. 4 or larger on a straight pull, the length of the box must be no less than eight times the trade diameter of the largest raceway.
  15. 4.0.0 – 4.1.0

    Slide 16 - 4.0.0 – 4.1.0

    • Device Boxes 26106-14
    • Pull Box with Conduit Runs Entering at Right Angles
    • • For conductors No. 4 or larger pulled at an angle, the length of the box must be no less than six times the trade diameter of the largest raceway.
    • • In addition to making a conductor pull easier, pull boxes can also be used to avoid conduit bends.
    • Performance Task
    • Select the minimum size pull or junction box for a given application.
    • This session will conclude with trainees practicing identifying the minimum size pull or junction box for a given application.
  16. 5.0.0 – 5.2.0

    Slide 17 - 5.0.0 – 5.2.0

    • Device Boxes 26106-14
    • Installing Boxes
    • • When installing boxes, the box must be correctly sized and listed for the application. Conductors must be protected against abrasion and the box supported properly. Boxes must remain accessible for future repair/maintenance.
    • • The requirements for receptacle locations in dwelling units are listed in NEC Section 210.52.
  17. 5.0.0 – 5.2.0

    Slide 18 - 5.0.0 – 5.2.0

    • Device Boxes 26106-14
    • Mounting Heights of Duplex Receptacles
    • • Receptacle mounting heights may be varied to suit the building use and structure.
    • • Remember that dimensions on electrical drawings are often given to the center of the box.
  18. 5.0.0 – 5.2.0

    Slide 19 - 5.0.0 – 5.2.0

    • Device Boxes 26106-14
    • Adjusting Mounting Heights
    • Avoid installing receptacles where they will cross the boundary between wall finishes.
  19. 5.0.0 – 5.2.0

    Slide 20 - 5.0.0 – 5.2.0

    • Device Boxes 26106-14
    • Gaps or Openings Around Outlet Boxes Must be Repaired
    • • Broken, jagged, or gapped wall surfaces must be repaired prior to installing the receptacle faceplate.
    • • Coordinate commercial installations to avoid interfering with the installation of other systems.
  20. 5.0.0 – 5.2.0

    Slide 21 - 5.0.0 – 5.2.0

    • Device Boxes 26106-14
    • Wire Nuts
    • • Wire nuts are color coded for different wire sizes. They are also categorized by voltage rating and application (e.g., copper to copper).
    • • Follow the manufacturer’s instructions when installing wire nuts.
  21. 5.0.0 – 5.2.0

    Slide 22 - 5.0.0 – 5.2.0

    • Device Boxes 26106-14
    • Stripping Tools
    • Be sure to choose the correct tool for the size of wire being stripped and make a clean, square cut.
  22. 5.0.0 – 5.2.0

    Slide 23 - 5.0.0 – 5.2.0

    • Device Boxes 26106-14
    • Stripping the Insulation
    • Insulation is typically stripped back by about half an inch, but may vary depending on the wire size and type of wire nut in use.
  23. 5.0.0 – 5.2.0

    Slide 24 - 5.0.0 – 5.2.0

    • Device Boxes 26106-14
    • Wires Installed in Wire Nut
    • • Turn the wire nut until the conductor is fully seated in the wire nut.
    • • A completed installation should provide a tight electrical connection between conductors.
    • • Always tuck the conductors back into the box so that they are not protruding when the final wall finish is applied.
  24. Wrap Up

    Slide 25 - Wrap Up

    • 3-2-1
    • 3 – Write 3 important things learned during class
    • 2 – Write 2 questions you have about the material
    • 1 – Write 1 thought you had about the material
    • Device Boxes 26106-14
  25. Next Session…

    Slide 26 - Next Session…

    • MODULE EXAM
    • Review the complete module to prepare for the module exam. Complete the Module Review as a study aid.
    • Device Boxes 26106-14