NCCR 26106-23 Flashcards
Outlet, Device, Pull, and Junction Boxes
Define electrical box
Metallic or nonmetallic boxes installed in an electrical wiring system to safely house electrical components and/or securely mount devices and electrical cables.
What are the three usual categories of electrical boxes?
Pressed steel with knockouts. Cast iron, aluminum, or brass with threaded hubs. Nonmetallic.
What are octagon and round boxes typically used for?
To mount luminaires on walls
What is the width of a typical octagon box?
4”
What are the typical depths of octagonal boxes?
1 1/4”. 1 1/2”. 2 1/8”.
What is the minimum depth of octagonal and round boxes?
1/2”
What does AWG stand for?
American Wire Gauge
What are the typical sizes for square boxes?
4” and 4 11/16”.
what are the typical depths of square boxes?
1 1/4”, 1 1/2”, and 2 1/8”
What is a wet location?
Any location subject to saturation with water or other liquids.
What is a damp location?
Any location subject to some degree of moisture, including partially protected outdoor locations and interior locations subject to a moderate degree of moisture.
How many conductors is a fitting worth?
One
How many conductors is a device strap worth?
Two
How many conductors is a looped conductor over 12” in the box?
Two
Up to how many grounding conductors is worth one conductor?
Four
What is the recommended height for wall recepticles?
15” from floor to bottom of box
What is a pull box (or junction box)?
A box-like enclosure made of sheet metal. It is used in conduit runs to make it easier to pull cables from point to point in long runs.
What length should a pull box be for a straight pull?
8 * the largest trade size of conduit
What is the equation to determine the distance of conductors pulled at an angle?
6 * the largest conduit + the sum of all the other conduits
What do you use to increase the capacity of an electrical box?
raised outlet covers
Where are the rules for box installations in the NEC?
Article 314, Part II
How deep does a pull box need to be?
Deep enough to allow proper installation of locknuts and bushings
When are blank covers to be used?
When the box is used as a junction
What can be used to increase the amount of usable space in a box?
Extension rings and outlet covers
How do you determine the maximum number of conductors in a box?
Look at NEC Table 314.16(A)
