Search results
Results from the WOW.Com Content Network
A three-wire three-phase circuit is usually more economical than an equivalent two-wire single-phase circuit at the same line-to-ground voltage because it uses less conductor material to transmit a given amount of electrical power. [3] Three-phase power is mainly used directly to power large induction motors, other electric motors and other ...
Current practice is to give separate services for single-phase and three-phase loads, e.g., 120 V split-phase (lighting etc.) and 240 V to 600 V three-phase (for large motors). However, many jurisdictions forbid more than one class for a premises' service, and the choice may come down to 120/240 V split-phase, 208 V single-phase or three-phase ...
One voltage cycle of a three-phase system. A polyphase system (the term coined by Silvanus Thompson) is a means of distributing alternating-current (AC) electrical power that utilizes more than one AC phase, which refers to the phase offset value (in degrees) between AC in multiple conducting wires; phases may also refer to the corresponding terminals and conductors, as in color codes.
The plotted line represents the variation of instantaneous voltage (or current) with respect to time. This cycle repeats with a frequency that depends on the power system. In electrical engineering, three-phase electric power systems have at least three conductors carrying alternating voltages that are offset in time by one-third of the period ...
NEMA 6 devices, while specified as 250 V, may be used for either 208 or 240 V circuits, generally depending on whether the building has a three-phase or split-phase power supply, respectively. The NEMA 6-20R or 6-30R found in many hotel and motel rooms is typically supplied with either split-phase or two phases of three-phase 208 V.
Lighting and general purpose receptacles are at 120 volts AC, with larger devices fed by three wire single-phase circuits at 240 volts. In commercial construction, three-phase circuits are often used. Common 3 phase configurations within a building are 208v/120 wye, 120/240 center tapped delta and 480v/277v wye. Lighting is usually fed by 277 V ...
A typical one-line diagram with annotated power flows. Red boxes represent circuit breakers, grey lines represent three-phase bus and interconnecting conductors, the orange circle represents an electric generator, the green spiral is an inductor, and the three overlapping blue circles represent a double-wound transformer with a tertiary winding.
Main page; Contents; Current events; Random article; About Wikipedia; Contact us