NCCER Electrical L1/M11 MIX

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NCCER Electrical L1/M11 MIX

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  1. Slide 1

    • Device Boxes 26111-14
    • NCCER Electrical
    • Level 1
    • Residential Electrical Services
  2. 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 26111-14
  3. 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 26111-14
  4. 2.2.0

    Slide 4 - 2.2.0

    • Device Boxes 26111-14
    • The general lighting load of the service entrance conductor is calculated by multiplying the buildings square feet by 3VA.
    • 45’
    • 65’
    • 45’ X 65’= 2,925sqft
    • 2,925sqft X 3VA= 8,775VA
    • General Light Load= 8,775VA
  5. 2.2.0

    Slide 5 - 2.2.0

    • Device Boxes 26111-14
    • To calculate how many circuits will be needed to support 8,775VA do the following steps
    • 120v X 20a = 2,400VA
    • 8,775VA / 2,400VA = 3.65 circuits
    • (you cannot have partial circuits)
    • 3.65 = 4 20amp Circuits to support light load
    • You are allowed to go with the least allowed, in this case 4, but you do not need anymore than that.
  6. 2.3.1

    Slide 6 - 2.3.1

    • Device Boxes 26111-14
    • Small Appliance Loads
    • NEC Section 210.11(C)(1) requires at least 2 120v, 20a small appliance branch circuits.
    • They are usually installed in the kitchen.
  7. 2.3.4

    Slide 7 - 2.3.4

    • Device Boxes 26111-14
    • NEC Section 220.53 permits the loads for four fixed appliances in a single-family dwelling only to be computed at 76% as long as they are not electrical heating, air conditioning, electric cooking, or electrical clothes dryer.
  8. 3.0.0

    Slide 8 - 3.0.0

    • Device Boxes 26111-14
    • The neutral loads of the electric range and clothes dryer are permitted by NEC Section 220.61 to be computed at 70% of the demand for the phase conductors since these appliances have both 120v and 240v loads.
  9. 4.1.0

    Slide 9 - 4.1.0

    • Device Boxes 26111-14
    • GFCI’s
    • When a current imbalance occurs, the sensor, which is a differential current transformers, sends a signal to the solid-state circuit, which activates the ground trip solenoid mechanism and breaks the hot load connection
  10. 4.1.0

    Slide 10 - 4.1.0

    • Device Boxes 26111-14
    • GFCI’s
    • They are required in:
    • Garages
    • Bathrooms
    • Kitchen Counters
    • Outdoor Receptacles
  11. 4.1.0

    Slide 11 - 4.1.0

    • Device Boxes 26111-14
    • GFCI’s
    • An imbalance as low as 4 milli-amps can set it off!
  12. 5.1.0

    Slide 12 - 5.1.0

    • Device Boxes 26111-14
    • The NEC says a few things can be considered as grounding points.
    • Metal underground water pipe 10’ or more in contact with the earth.
    • Metal frame of the building
    • Electrode encased in 2” of concrete and the electrode must be 20’ long and electrically continuous.
    • Rod driven 8’ into the earth.
  13. 5.1.2

    Slide 13 - 5.1.2

    • Device Boxes 26111-14
    • The Grounding Electrode Conductor can be made of these materials.
    • Copper
    • Aluminum
    • Copper-Clad Aluminum
    • The GEC does not need to be identified by green, or green yellow markings if it is insulated
  14. 6.2.0

    Slide 14 - 6.2.0

    • Device Boxes 26111-14
    • When the voltage to ground is only 300v or less, you are allowed to have the service drop over a residential driveway 12’ to its lowest point as opposed to 15’ if the voltage were higher.
  15. 7.0.0

    Slide 15 - 7.0.0

    • Device Boxes 26111-14
    • NEC Section 230.70
    • Require that the service disconnecting means be installed in a readily accessible location - either outside or inside of the building.
  16. 8.1.1

    Slide 16 - 8.1.1

    • Device Boxes 26111-14
    • NM cable = Romex
    • Romex is only a product by the brand Southwire, but is the most used NM cable used in industry.
  17. 8.1.4

    Slide 17 - 8.1.4

    • Device Boxes 26111-14
    • Type USE and SE cable should be supported every 30” and used outside.
  18. 9.0.0

    Slide 18 - 9.0.0

    • Device Boxes 26111-14
    • NEC Article 250, Part IV
    • Generally requires that all metallic enclosures, raceways, and cable armor be grounded.
    • Where located in wet locations
    • Where electrical contact with metal
    • Where equipment operates with any terminal at over 150v to ground
  19. 10.1.0

    Slide 19 - 10.1.0

    • Device Boxes 26111-14
    • The feeder consists of all conductors between a service equipment and the final overcurrent device
    • The conductors that extend from the panelboard to the various outlets are called branch circuits.
  20. 12.1.0

    Slide 20 - 12.1.0

    • Device Boxes 26111-14
    • When the wall material is Combustible, outlets boxes must be installed flush.
    • In wood or sheetrock would be two examples
    • When the wall material is NON Combustible, outlet boxes can be recessed ¼” into the wall material.
    • In plaster or stone would be two examples
  21. 16.0.0

    Slide 21 - 16.0.0

    • Device Boxes 26111-14
    • NEC Article 680
    • Cover the rules governing pools and such
    • For hot tubs, at least one 120V 20A GFCI circuit must be installed within 10’ of the inside wall of the hot tub. See Figure 54
  22. Wrap Up

    Slide 22 - 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 26111-14
  23. Next Session…

    Slide 23 - Next Session…

    • MODULE EXAM
    • Review the complete module to prepare for the module exam. Complete the Module Review as a study aid.
    • Device Boxes 26111-14