Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
3 Cards in this Set
- Front
- Back
|
JUG HANDLE? |
A term used to describe the type of bend that must be made with certain cable types; bending them in the shape similar to a "handle" on a jug will help satisfy NEC bending requirements. |
|
|
RUNNING BOARDS? |
Are pieces of board lumber nailed or screwed to the joists in an attic or basement; the purpose of using running boards is to have a place to secure cables during the rough in stage of installing a residential electrical system. |
|
|
What are the requirements for installing nonmetallic sheathed cable( Type NM ) and where can it be used? |
1. The cable must closely follow the surface of the building finish or be secured to a running board. 2. The cable must be protected by rigid metal conduit, EMT or other approved means. Where passing through a floor the cable must be enclosed in a rigid metal conduit, intermediate metal conduit, electrical metallic tubing, or schedule 80 PVC rigid conduit extended at least 6 inches (150mm) above the floor. Where the cable is run across the bottom of joists in unfinished basements and crawl spaces, it is permissable to secure cables not smaller than two 6AWG conductors or three 8AWG conductors directly to the bottom edge of the joists. Smaller cables must be run either through boarded holes in joists or on running boards.Section 300.4(D) requires cables that are run along the side of framing members to be installed at least 1 1/4" from the nearest edge of studs, joist, or rafters.Type NM cable is permitted to be installed in a listed conduit or tubing. 4. Type NM cable is run through a hole that has an edge closer than 1 1/4 " to the edge of the framing members , a metal plate at least 1/16" thick must be used to protect that spot from nails or screws that could penetrate the cable sheathing. 5. If the cable is placed in a notch or in wood studs, joist, rafters, or other wood members, a steel plate must protect the cable and be at least 1/16" thick. 6. If the cable is run along a framing member, where the cable is closer than 1 1/4" to the edge, metal protection plates at least 1/16" thick must be used to protect the cable. 7. If Romex is run across the top of the floor joist, or within 7' of an attic floor or floor joist, the cable must be protected by guard strips that are at least as high as the cable . The 7' rule is also applied when Romex is run across the face of rafters or studding in an attic entrance. Where the attic space is not accessible by permanent stairs or ladders, protection is only required within 6' of the nearest entrance of the scuttle hole or attic entrance. Where the cable is installed along the side of rafters, studs, or floor joist in an attic neither guard strips nor running boards or required, but the cable must be kept at least one and a quarter inch from the edge of the framing members. 8. Requires nonmetallic sheathed cable to be secured by staples, cable ties, straps, hangers or similar fittings designed and installed so as not to damage the cable and intervals not exceeding four and a half feet and within 12"of every cabinet, box or fitting. 9. Section 334.30(A) states that type NM cables that run horizontally through framing members that are spaced less than 4 and 1/2 ft apart and that pass through boarded or punched holes in framing members without additional security are considered supported by the framing members. Cable ties or staples are not required as the cable passes through these members. Where the cable terminates at a single gang non-metallic electrical box that does not contain cable clamps the cable must be secured within 8" of the Box according to an exception to section 314.17(c) Section 3 3 4 .30 be allows type NM cables to not be supported in these situations. Where the cable is fished between access points or concealed in finished buildings and supporting is impractical. Where the cable is not more than 4 and 1/2 ft from the last point of support for connections within an accessible ceiling to luminaires (light fixtures). This allows short, unsupported length of type NM cable for luminaire connections. Type NM cable is allowed to be used in one and two family homes, including their attached or detached garages and storage buildings. ⚠️ Check with the authority having jurisdiction to make sure type NM cable is permitted in one and two family homes in your area of the country. |
