Wiring problems and mistakes are all too common, and if left uncorrected have the potential to cause short circuits, shocks and even fires. Single plastic boxes do not require internal cable clamps, but the cable must be stapled within 8 in. How do you secure a NM or Romex wire inside a plastic electrical box? Boxes with wire clamps are often pushed into the wall (old work boxes) where no staples can be placed, but they have the clamp to prevent the wire from pulling out of the box. The wires need to be stapled within 8 inches of the box, or use an old work box metal or plastic with internal cable clamps.
I am using plastic electrical boxes in my home theater. Some electrical boxes come equipped with cable clamps, some for your nonmetallic NM (Romex/Loomex) cable, others with cable clamps for your metal-sheathed BX (armored cable AC ), and still others with no cable clamps just knock-outs that you can install your own cable clamps in. Plastic electrical boxes should only be used with NM wire, do not use with BX wire. How to choose the proper type of electrical box when wiring electrical receptacles (wall plugs or outlets ). Shown above, the rotating swing-clamps on the plastic old work box are open for illustration (yellow arrow, photo at above left).
For the related rules regarding Plastic boxes and NM cables look at 314. With NM boxes this would be via the integral cable clamps that are built into the boxes. Posted November 13, 2002 at 10:02 PM Why do so many installers resent doing as required by the NEC?ALL jurisdictions that I am aware of require the licensee of an electrical license to install per the NEC or some modification ( by the State or Local Munincipality) when the license is issued. Shop our selection of Clamp, Conduit Fittings in the Electrical Department at The Home Depot. Carlon 1/2 in. PVC Conduit Clamp (Case of 25 25-Packs). Less grounding involved..and far easier with built-in cable clamps. And far easier with built-in cable clamps. Plastic boxes generally are for type NM wire only (Romex), meaning that in most localities they can only be used in small residential work (1 & 2 family homes).
Cable Clamps In Plastic Boxes (electrical)
1) Does a plastic box require clamping, or just metal boxes? I am replacing an existing fiberglass double-gang electrical box with a PVC triple-gang old-work box (a Carlon B355R box:. The junction boxes have holes for romex clamps which were punched out in which romex enters. Posted May 12, 2002 at 03:08 PM if the intent was to secure the wire via an RX clamp that is not there, then it would not be kosher. Marshall – you never did say if these boxes were plastic or metal.. in defense of inspectors: it is almost impossible for an inspector to check every single box/connection/clamp etc. Lighting & Electrical. What I’m looking for are the little plastic grommets that snap into the knockouts on breaker panels and then hold the romex into the box. They speed install time (just push the wire in) while reducing a margin of error (overtightening). NM’s plastic sheathing does not protect the wires much, so keep it out of harm’s way. Article about installing a remodel electrical box. When the screw is first turned, the plastic clamp arm swings away from the body and stops at a plastic tab.