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Power supplies for standard appliances, may they be for home or office use, are available in either alternating current or direct current. Normally, the simple action of plugging a power cord into a wall socket draws the former. In the event the appliance requires a different level of voltage or current, a step-up or step-down transformer can serve as an intermediary to regulate the power to the desired level. This works perfectly well when devices are moved crossed borders.
Programmable versions of supply take in a certain feed of power and produce a set of outputs in accordance to the set needs. As such, there is no need to implement various types of devices to convert the supply as one suffices the task. This also enables power supplies in lower or higher voltage depending on the needs of the machines. By affixing voltage multipliers, higher levels can be produced by doubling, tripling or even quadrupling the input voltage. These multipliers are also used to convert alternating current inputs to higher direct current outputs if the need arises.
Uninterruptible power supply is used to cater as its name implies. By drawing power from a main source, it also charges a battery power cell within. In the event main power is interrupted, battery power takes over thus ensuring continuous power.