Electrical cable is available with 3 or 4 wires running through the sheathing. Cable with 3 wires is referred to with labels like 14/2 and 12/2, where the two represents the black and white, current carrying wires in the cable. The other wire, the ground wire, is ignored in this labeling. Cable with 4 wires is referred to as 14/3 or 12/3 cable. Here 3 wires carry electricity, the black, red and white. All household cable is available with 2 or 3 current carrying wires and one ground.
In the center of each plate notch, cut a second, 3/4 inch notch for the cable. Make the depth about 1/2 inch to accept the cable thickness, but keep the entire notch depth to a maximum of 7/8 inch for load-bearing 2x4 studs and 1-7/16 inches for non load-bearing studs.
To install a fixture using a coupler, thread the rod into the center hole in the mounting strap and set the rod depth so the fixture base will fit snuggly against the ceiling when it’s installed. Measure the depth of the cover plate to estimate placement, precision isn’t necessary here, small adjustments can be made to the position after the installation by turning the coupler nut. Be sure all the wires are stripped for splicing, hold the fixture up and feed them through the threaded rod into the outlet box.
By code the junction box must remain accessible, so look for a spot where the cover plate will blend. Use a 3x2½ inch device box like the ones use for wall outlets and set it at the same level as the existing wall receptacles to minimize visual impact.
Hold the wires together so the ends match up and twist them together in a clockwise direction using lineman pliers. Make 1 or 2 turns to form a solid union being careful not to dig into the copper with the plier jaws.
Unintended flow of electricity from a circuit to a non-circuit conductor. A short can occur when a hot circuit wire touches anything other than its intended contact. A short will cause a circuit breaker, fuse or gfci to instantly shutoff electrical flow to prevent injury or fire.
Use a drywall saw and knife to cut drywall and gypsum board plaster, use a reciprocating or keyhole saw to cut wood lath plaster. With the framing exposed, use a small saw to cut two vertical kerfs in the plate about an inch apart and then use a wood chisel to chip out a notch about ½inch or so deep, between the cuts.
Two or more wires housed in a protective sheathing is referred to as electrical cable. Armored, UF and NM are all names for household electrical cable. Each cable type is available for different wire gauge. Standard household electrical cable ranges from 14 awg (american wire gauge) to 6 awg, with 14 having the smallest conductors and 6 having the largest. In household electrical systems 14 gauge wire is used for 15 amp circuits, 12 gauge for 20 amp circuits, 10 awg for 30 amps, 8 awg for 40amps and 6 awg for 50 and 60 amp circuits.