Direct current

A form of eletricity where the electrical potential (voltage) does not vary, and so the electrons travel in only one direction along the conductor. Found in batteries and other chemical-eletric devices, and where ac->dc converters are used. Disadvantage: transformers are much more difficult to create with DC.

abbreviation DC, flow of electric charge that does not change direction. Direct Current is produced by batteries, fuel cells, rectifiers, and generators with commutators. Direct current was supplanted by alternating current (AC) for common commercial power in the late 1880s because it was then uneconomical to transform it to the high voltages needed for long-distance transmission. Techniques that were developed in the 1960s overcame this obstacle, and direct current is now transmitted over very long distances, even though it must ordinarily be converted to alternating current for final distribution. For some uses, such as electroplating, direct current is essential.

Direct current. (Elec.)

(a)

A current flowing in one direction only; -- distinguished from alternating current. When steady and not pulsating a direct current is often called a continuous current.

(b)

A direct induced current, or momentary current of the same direction as the inducing current, produced by stopping or removing the latter; also, a similar current produced by removal of a magnet.

© Webster 1913