Guidelines to basic electrical wiring in your home and Guidelines to electrical wiring around your home or other locations. An “outlet” is any point in an electrical system where current is taken out of the system in order to supply power to the attached electrical equipment. An outlet can be one of two basic types: A Basic Residential Electrical Wiring Circuits Rough In and Branch Circuits Guidelines Do NOT mix different wire sizes on the same branch circuit. Type NM cable must be stapled within 12" of metal boxes, 8" of plastic boxes and every 4½ feet thereafter. Proper connectors must be used where NM cable enters metal cabinets, boxes or panel boards.