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What is the maximum spacing requirement for securing NM-cable (nonmetallic-sheathed cable)?
Friday, June 15, 2018
NM-cable must be secured and supported every 4.5-feet (1.4-meters) by staples, listed cable ties, straps, hangers or similar fittings, or other similar fittings that are designed and installed so that they do not damage the cable. A second requirement is that the cable be secured 12-inches (300-millimeters) of the cable entry into any enclosure, such as an outlet box, junction box, cabinet or fitting. Also, flat cables should not be stapled on edge. Cables that are protected from damage by a raceway do not have to be secured inside the raceway (NEC 334.30).
When the cable is within an accessible ceiling of a one-, two-, or multi-family dwelling that is dropped or suspended, the cable can be run up to 4.5-feet to a connection point of a luminaire (light fixture) or other piece of electrical equipment. So, if luminaires in an accessible ceiling are no more than 4.5-feet apart, the cable can be run from fixture-to-fixture without support or junction boxes [NEC 334.30 (B)(2)].
When the cable is installed through bored holes in studs, the studs cannot be more than 4.5-feet apart and, again, the cable must be supported within 12-inches of a box [NEC334.30(A)]. The hole in a stud cannot be less than 1.25-inches from the face of the stud, or 1/16-inch thick steel plate must be installed to protect the cable from drywall nails or other wall penetrations [300.4(B)(2)].
Also, see our blog post What are the code requirements for NM-cable (nonmetallic-sheathed cable or Romex®) in an attic?
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Here’s links to a collection of our other blog posts about ELECTRICAL WIRING:
Is it legal to bore holes through roof trusses to install wiring?
• Which house appliances need a dedicated electrical circuit?
• Can a short circuit cause a high electric bill?
• What is the maximum spacing requirement for securing NM-cable (nonmetallic-sheathed cable)?
• Is it alright to just put wire nuts on the end of unused or abandoned NM-cable or wiring?
• What causes copper wires to turn green or black in an electric panel?
• What are typical aluminum service entrance wire/cable sizes for the electrical service to a house?
• Why is it unsafe to bond neutral and ground wiring at subpanels?
• Should I get a lightning rod system to protect my house?
• Why is a strain relief clamp necessary for the cord connection to some electric appliances?
• Does a wire nut connection need to be wrapped with electrical tape?
• What is the minimum clearance of overhead electric service drop wires above a house roof?
• What are the requirements for NM-cables entering an electric panel box?
• What is the color code for NM cable (Romex®) sheathing?
• Why is undersize electric wiring in a house dangerous?
• What causes flickering or blinking lights in a house?
• Why are old electrical components not always "grandfathered" as acceptable by home inspectors?
• How can I find out the size of the electric service to a house?
• Can old electrical wiring go bad inside a wall?
• What is an open electrical splice?
• What are the most common electrical defects found in a home inspection?
• What is the life expectancy of electrical wiring in a house?
• What is an "open junction box"?
• How dangerous is old electrical wiring?
• I heard that aluminum wiring is bad. How do you check for aluminum wiring?
Visit our ELECTRICAL page for other related blog posts on this subject, or go to the INDEX for a complete listing of all our articles.
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