Definitions - Fluke 43B Application Manual

Active Power
The Active Power (Watt) is that portion of electrical power that is real. It
includes heat losses. Utility charges are based on Watts.
Apparent Power
Apparent Power (VA) is the product of the rms voltage and current which
relates to the effective load seen by the transformer and current carrying
conductors.
Black out (see outage)
Brown out (see sag)
Cos ϕ ϕ ϕ ϕ (see Displacement Power Factor, DPF)
Displacement Power Factor, DPF (Cos ϕ ϕ ϕ ϕ )
The ratio of real power to apparent power. Displacement Power Factor is the
cosine of the phase angle between the fundamental current and the
fundamental voltage (cos ϕ). Inductive loads cause current to lag behind
voltage, while capacitive loads cause current to lead voltage.
The displacement power factor uses only the fundamental of the signal for its
calculation. (see also: Power Factor)
DPF Interpretation
0 to 1 current leads or lags, device is consuming power.
1 current and voltage in phase, device is consuming power.
-1 current and voltage in phase, device is generating power.
-1 to 0 current leads or lags, device generating power.
Dropout
A discrete voltage loss. A voltage sag* for a very short period of time
(milliseconds).
Chapter 7

Definitions

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