Schneider Electric 4000 True power factor-seepower factor, Voltage transformer VT-seepotential

63230-300-212	Glossary
April 2001

rms—root mean square. Circuit monitors are true rms sensing devices. See also harmonics (rms).

sag/swell—fluctuation (decreasing or increasing) in voltage or current in the electrical system being monitored. See also, voltage sag and voltage swell.

scale factor—multipliers that the circuit monitor uses to make values fit into the register where information is stored.

SMS—see System Manager Software.

synchronized demand—demand intervals in the circuit monitor that can be synchronized with another device using an external pulse, a command sent over communications, or the circuit monitor’s internal real-time clock.

System Manager Software (SMS)—software designed by POWERLOGIC for use in evaluating power monitoring and control data.

system type—a unique code assigned to each type of system wiring configuration of the circuit monitor.

thermal demand—demand calculation based on thermal response.

TIF/IT—telephone influence factor used to assess the interference of power distribution circuits with audio communications circuits.

Total Harmonic Distortion (THD or thd)— indicates the degree to which the voltage or current signal is distorted in a circuit.

total power factor—see power factor.

transient—sudden change in the steady-state condition of voltage or current.

troubleshooting—evaluating and attempting to correct problems with the circuit monitor’s operation.

true power factor—seepower factor.

undervoltage—decrease in effective voltage to less than 90% for longer than one minute.

VAR—volt ampere reactive.

VFD—vacuum fluorescent display.

voltage interruption—complete loss of power where no voltage remains in the circuit.

voltage sag—a brief decrease in effective voltage lasting more than one minute.

voltage swell—increase in effective voltage for up to one minute in duration.

voltage transformer (VT)—seepotential

transformer.

voltage unbalance—percentage difference between each phase voltage with respect to the average of all phase voltages.

waveform capture—can be done for all current and voltage channels in the circuit monitor.

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