Measurement Computing WavePort 312P rev.1.0 - Manual (Page 77)

PowerVista User’s Manual Glossary 11-1
Glossary
CBEMA Curve
A set of curves developed by the Computer Business Equipment Manufacturers Association (CBEMA), that
represent the withstand capability of computers to voltage variations. CBEMA curves are defined by voltage
change and by the duration of the voltage excursion.
Characteristic Harmonic
Harmonics that are produced by semiconductor converter equipment in the course of normal operation. In a six-
pulse converter, the characteristic harmonics are the non-triplen odd harmonics, for example, the 5th, 7th, 11th,
13th, etc., or
h = kq ±±±± 1
k = any integer
q = pulse number of converter
Demand Information
Information captured on a single cycle basis and analyzed to give fundamental and RMS results of volts, amps,
watts, vars and pf. Demand can include frequency if being monitored.
Displacement Power Factor
The displacement power factor is the ratio of the active power of the fundamental component, in watts, to the
apparent power of the fundamental component, in volt-amperes.
Flicker
Variations of voltage over time that bring notice or uncomfortable sensation via human perception, when
affecting the luminescence of a light source. For older flicker curves, lights were mostly incandescent.
Filter
A passive tuned circuit that presents a low impedance "sink" to currents at a given frequency.