* American wire gage B&S in .NET framework

Generating DataMatrix in .NET framework * American wire gage B&S

or one 15-ampere circuit for not more than every 375 square feet of oor area Outlets supplied by these circuits should be equally divided among the circuits Feeder circuits should also be used It is strongly recommended that consideration be given to the installation of branch circuit protective equipment served by appropriately sized feeders located throughout the house, rather than at a single location Small appliance branch circuits should also be installed There should be in-home wiring service at least one three-wire, 120/240-volt, 20-ampere small-appliance branch circuit that is equipped with split-wired receptacles for all convenience outlets in the kitchen, breakfast and dining room, and family room Two two-wire, 120-volt, 20-ampere branch circuits are equally acceptable Cable of several different types can be used for branch wiring Armored cable, commonly referred to as BX, is available in 250foot rolls for use where local codes permit BX is hard to work with and needs some attention to details once the metal shield has been cut See Figures 8-2 and 8-3 Armored Cable Fittings Install armored cable ttings as follows: To protect wires, install antishort bushing in end of cable (754 series) Antishort bushings are not required when using screw-in connectors and couplings (044 and 045 series) Slip connector onto cable allowing 6 to 8 inches of wire to protrude from tting Tighten screw(s) (except 044 and 045 series) Remove locknut from tting

FIGURE 8-3 Installing fittings for armored or flexible metal conduit (Halex)

Insert tting (now with wires protruding) into knockout in outlet box Turn locknut on tting from inside the box and tighten by tapping with screwdriver blade until teeth bite into box Tug on cable to test connection

Secure cable with staples (625, 720, and 730 series) within 12 inches of the box and one for every four 1/2 feet of cable run Be careful not to damage cable insulation or conductors

044 and 045 screw-in series are used for exible metal conduit only 05803 connector is to be used with armored cable only 153 series combination couplings can be used for EMT and exible metal conduit only 15803 duplex connectors may be used on nonmetallic cable as well as armored and exible metal conduit

Romex cable is used for branch circuits and is easier to work with A cable stripper is used to strip off the rst coating of insulation Then, a knife or wire cutter is used to cut away any loose materials to expose the uninsulated copper wire and the black- and white-jacketed conductors, (In three-wire cable there is also found a red-jacketed conductor See Figure 8-4 Figure 8-5 shows how Romex is used to wire a branch circuit with a receptacle Figure 8-6 shows how to properly wire receptacles and switches in branch circuits Figure 8-7 illustrates how branch circuits are loaded to balance the load on different phases Single-phase and three-phase loading are shown Of course, the proper wire should be used for each of the circuits Service Entrance Cable Power is brought from the pole or transformer into the rear of the house (in some cases the lines are underground) by means of three wires one black, one red, and one white or uninsulated These wires may be three separate ones, or they may be twisted together to look like one cable Once the cable is connected to the house, it is brought down to the meter by way of a sheathed cable with three wires: one red, one black, and one uninsulated (ground or neutral) The stranded, uninsulated wire is twisted at the end to make its connection See Figure 8-8

Wire size depends on the load to be applied to the line The square footage of the house determines the amount of minimum service capacity needed (125 amperes, 150 amperes, or 200 amperes) From the outside, the cable enters the house and is connected to the distribution box located somewhere easily accessible, such as in the basement From the distribution box, the branch circuits run to all parts of the house Underground Feeders and Branch Circuit Cable This type of cable is for direct burial and is made with polyvinyl chloride