With five different wiring methods installed in this box, including two electrical metallic tubings, two rigid nonmetallic conduits, one nonmetallic sheathed cable (Type NM-B), two surface metal raceways, and two Type AC cables, there is just not enough free space in this 4 inch x 1 1/4 inch square box. If we considered conductors sized at 12 AWG for each circuit, with two wires in each raceway, and cable, including an equipment grounding conductor in the RNMC and NM-B cable, we would end up with a total of 18 of the 12 AWG conductors, plus one additional for the three equipment grounding conductors, for a grand total of 19 conductors. As per Table 314.16(A), the maximum number of 12 AWG conductors allowed in this size metal box is only eight!
Nay, they probably will add more wires, or add some extension rings. If they do, then the problem gets worse because of the 3 inch rule that calls for all wires to capable of extending from the edge of the last ring or rings with no splices.
**2005 NEC Reference:
"300.14 Length of Free Conductors at Outlets, Junctions, and Switch Points
**At least 150 mm (6 in.) of free conductor, measured from the point in the box where it emerges from its raceway or cable sheath, shall be left at each outlet, junction, and switch point for splices or the connection of luminaires (fixtures) or devices. Where the opening to an outlet, junction, or switch point is less than 200 mm (8 in.) in any dimension, each conductor shall be
long enough to extend at least 75 mm (3 in.) outside the opening.
* Exception: Conductors that are not spliced or terminated at the outlet, junction, or switch point shall not be required to comply with 300.14."
*
Oh my – I took the cover off and found a box full of cat #3 phone wire and they had used old runs because it was easy. I am in real trouble now because I flagged it as a problem and it was not
Oh well live and learn - Next time I pull the cover plate - Crap I will probably get in trouble because that is probably invasive like taking the screws out of an attic hatch or the screws off of the panel on an electrical box. – Just can’t win
Are you looking for what I would advise the person to do…honestly…I would tell them to take that freakin blank off…add a 4" x 2 1/8" square extention ring and HOPE the wires meet the requirement…or they can wirenut and pigtail to get the length…they wont count in the calculation anyway… and replace the cover and be happy…about all I would tell them.
