List of Specific Industries
North American Industry Classification System (NAICS) codes for this industry
Romex cable is installed between a circuit breaker in the service entrance panel box and the particular devices to be powered — wall switches, light fixtures, receptacles, ceiling fans, kitchen appliances, clothes washer, furnaces, etc. Size of electrical cable, cable wire configuration (presence of ground wires, accepted types of insulation, etc.), types of receptacles, and the correct types of circuit breakers and service entrance panels are all defined by the NEC or other codes.
The power usually carried on power poles for use in homes is single phase power. Three phase power is usually rare in homes, is frequently found in manufacturing and other kinds of businesses such as dairy farms. Higher voltages and three-phase power provide electrical energy more efficiently and require smaller, less expensive cables and conductors. It is common to see 480 VAC used in businesses with extensive overhead lighting and large coolers or freezers.