Effektretning

Effektretning is a term commonly used in Danish and Norwegian technical literature to denote the direction in which energy or an effect is transmitted by a system. Because the concept is highly context dependent, definitions are given within the relevant discipline—for example electrical engineering, acoustics, hydraulics, and control theory.

In electrical engineering, effektretning describes the direction of power flow. Under standard sign conventions, power is considered to flow from sources toward loads. A positive power value indicates energy transfer in the forward direction, whereas negative power indicates energy absorption by a component. The local energy flow in electromagnetism is also described by the Poynting vector, which points in the effektretning of the field.

In acoustics and fluid systems, effektretning denotes the direction in which sound, pressure, or fluid power propagates—from source to destination. In control theory, it may refer to the direction in which a control action produces an observable effect on the system output.

Practical diagrams often use arrows to represent effektretning, with polarity markings to show the intended direction of energy transfer. The concept emphasizes that the "direction" of energy or effect can change with configuration, operating mode, or the presence of energy recycling (for example regenerative systems).

See also: power flow, sign convention, energy transfer, Poynting vector.