If you use a clamp for two cables, it must be rated for two cables of the applicable size. For example the Arlington NM94 is made for a 1/2″ trade size knockout and can be used with one or two 14/2 or 12/2 NM cables.

Can you put two wires knockout?

Never run two cables into the box through the same knockout opening with pre-installed cable clamps. Each cable requires its own knockout opening and clamp. For installed clamps (whether they’re metal or plastic), no more than 2 wires should be installed in each connector of this type.

How many nm cables can be inserted into a connector?





The number allowed is based on the UL-rating. Most NM-connectors are UL-approved for securing only one NM-cable to a panel box. But some are rated for two #14 or #12 cables, and we know of one 3/4” connector that is rated for three.

Can you use Romex with metal boxes?

Even if the device does not complete the ground, Romex or NM wiring can always be used with metal electrical boxes by attaching the bare or green grounding wire to the box by a screw.

Can you run nm cable exposed?

The National Electrical Code forbids the use of NM cable in situations where it is exposed in a manner where physical damage is possible.

How many wires can you run through a stud hole?

The Answer. According to the National Electrical Code, you can have 4 12/2 nonmetallic sheathed cables through a single bored hole that is fire- or draft-stopped using thermal insulation, caulk, or sealing foam, or where proper spacing is not maintained for more that 24 in.

How do you install Romex in a metal box?






Quote from Youtube video: Put the wire through the box put the reducer on the other side of the box. Now put your nut on and tighten it up to the conduit. The outgoing.

How do you protect exposed nm wire?

Nonmetallic-sheathed cable must be protected from physical damage by rigid metal conduit (RMC), intermediate metal conduit (IMC), Schedule 80 PVC conduit, Type RTRC-XW conduit, electrical metallic tubing (EMT), guard strips, or other means approved by the authority having jurisdiction (AHJ) [334.15(B)].

Is it legal to put Romex in conduit?

No, you can not run your Romex wiring in conduits. What you’re looking at in the code book is referring to THHN and other wiring, that while insulated with a single coat is not insulated with a second covering and bound to 2 or 3 other wires.

Are two NM cables allowed to be supported under 1 staple?

Secure only one cable under each fastener, in most cases. Sometimes it is permissible to secure two 2-conductor (plus ground) cables under a single staple, for example, but it is preferable not to double up cables. It is not permissible to secure more than one 3-conductor cable under a single staple.

Can Romex be bundled together?



If all of these cables are 14/2 romex serving general lighting/receptacle loads, then you can bundle 3 together at most before you have to derate them.

Can you staple Romex to bottom of joists?

It is okay to staple Romex along the floor joists, provided you keep it at a safe distance from the edge. This will help you protect it from screws and nails and any critters that may be crawling along the edges – since that is where insects usually decide to burrow. You can also run Romex THORUGH floor joists.

How often does Romex need to be supported?

15. Romex Wiring Support, NEC 336-18: Stapled, in a manner that does not damagethe cable, within 12″ of electric boxes; every 4-1/2 ft. intervals, and clamped to box. Cables run through holes in studs, rafters of floor joists are considered supported at those points.

Can you use metal staples on Romex?



Most metal and plastic staples or ‘wire holders’ can hold stacks of up to six to eight (6 to 8) Romex wires under them. You can stack even more if you can fit them or use thinner wires. However, it is not permitted by code to stack more than one 3-conductor cable under a staple, be it metal or plastic.

Can flat NM cable be stapled on edge?

Flat cables shall not be stapled on edge. Sections of cable protected from physical damage by raceway shall not be required to be secured within the raceway.

How far can you run Romex?

As an example, for a 120-volt circuit, you can run up to 50 feet of 14 AWG cable without exceeding 3 percent voltage drop.



For 240-volt circuits:

14 AWG 100 feet
12 AWG 120 feet
10 AWG 128 feet
8 AWG 152 feet
6 AWG 188 feet


Can you bury Romex without conduit?



Buried or exposed wiring will need to be listed for its application. Underground feeder wiring can be directly buried without a conduit with a minimum of 24 inches of cover. Any wiring placed inside intermediate metal or rigid metal conduits will require at least six inches of ground cover.

Where is Romex not allowed?

To give you an overview of what the National Electrical Code (NEC) regulations state, Romex wire shouldn’t be left exposed anywhere in the house, be it the basement, attic, or the home itself. In other words, the installation above is not compliant with the relevant codes.