Commercial
Three-phase power
Three-phase power uses three alternating currents offset in time, giving smoother power for large motors and commercial equipment.
OSHA's electric power glossary says overhead AC transmission lines carry 3-phase current. It lists service of 120/240 volts single phase for residential customers, and 480Y/277 or 208Y/120 for commercial or light industry customers.
Many commercial buildings have three-phase service because air conditioning units, pumps and machinery need it. Homes mostly have single phase. A transformer and switchgear distribute it inside the site. See commercial electrician.
Related terms
Sources
TECL #21005 · Family owned since 1988
Need an electrician in Southlake?
Call and tell us what is going on. A photo of the panel label or the problem helps us come prepared. Quotes on new installations are free.
