Search results
Results from the WOW.Com Content Network
In the power systems analysis field of electrical engineering, a per-unit system is the expression of system quantities as fractions of a defined base unit quantity. . Calculations are simplified because quantities expressed as per-unit do not change when they are referred from one side of a transformer to t
Stand-alone switched-mode power supply An adjustable switched-mode power supply for laboratory use. A switched-mode power supply (SMPS), also called switching-mode power supply, switch-mode power supply, switched power supply, or simply switcher, is an electronic power supply that incorporates a switching regulator to convert electrical power efficiently.
A common prefixed derived unit is "kilovolt-ampere" (symbol kVA). The VA rating is limited by the maximum permissible current, and the watt rating by the power-handling capacity of the device. When a UPS powers equipment which presents a reactive load with a low power factor, neither limit may safely be exceeded. [5]
In electrical engineering, power conversion is the process of converting electric energy from one form to another. A power converter is an electrical device for converting electrical energy between alternating current (AC) and direct current (DC). It can also change the voltage or frequency of the current.
A generator interlock kit (or a transfer switch), eliminates the need for extension cords to power appliances. [2]Like a transfer switch, an interlock kit lets the generator energize the panel and all of its circuits (up to the load capacity of the generator); not just corded appliances.
The purpose of a balanced power system is to minimize the noise coupled into sensitive equipment from the power supply. Unlike a three-wire distribution system, the grounded neutral is not distributed to the loads; only line-to-line connections at 120 V are used.
When utility power returns for a minimum time, the transfer switch will transfer the house back to utility power and command the generator to turn off, after another specified amount of "cool down" time with no load on the generator. A transfer switch can be set up to provide power only to critical circuits or to entire electrical subpanels ...
At the power station, an electrical generator converts mechanical power into a set of three AC electric currents, one from each coil (or winding) of the generator. The windings are arranged such that the currents are at the same frequency but with the peaks and troughs of their wave forms offset to provide three complementary currents with a ...