Schneider Electric 4000 Potential transformer PT-also known as a, Glossary 63230-300-212 April

Glossary	63230-300-212
	April 2001

K-factor—a numerical rating used to specify power transformers for non linear loads. It describes a transformer’s ability to serve nonlinear loads without exceeding rated temperature rise limits.

KYZ output—pulse output from a metering device where each pulse has a weight assigned to it which represents an amount of energy or other value.

LCD—liquid crystal display.

line-to-line voltages—measurement of the rms line-to-line voltages of the circuit.

line-to-neutral voltages—measurement of the rms line-to-neutral voltages of the circuit.

logging—recording data at user-defined intervals in the circuit monitor’s nonvolatile memory.

maximum value—highest value recorded of the instantaneous quantity such as Phase A Current, Phase A Voltage, etc., since the last reset of the minimums and maximums.

minimum value—lowest value recorded of the instantaneous quantity such as Phase A Current, Phase A Voltage, etc., since the last reset of the minimums and maximums.

nominal—typical or average.

onboard—refers to data stored in the circuit monitor.

option cards—optional, field-installable accessories for the circuit monitor that expand the I/O and Ethernet communications capabilities because they can be inserted into slots in the circuit monitor.

overvoltage—increase in effective voltage to greater than 110 percent for longer than one minute.

parity—refers to binary numbers sent over the communications link. An extra bit is added so that the number of ones in the binary number is either even or odd, depending on your configuration). Used to detect errors in the transmission of data.

partial interval demand—calculation of energy thus far in a present interval. Equal to energy accumulated thus far in the interval divided by the length of the complete interval.

peak demand current—highest demand current measured in amperes since the last reset of demand. See also peak value.

peak demand real power—highest demand real power measured since the last rest of demand.

peak demand voltage—highest demand voltage measured since the last reset of demand voltage. See also peak value.

peak demand—highest demand measured since the last reset of peak demand.

peak value—of voltage or current is the maximum or minimum crest value of a waveform.

phase currents (rms)—measurement in amperes of the rms current for each of the three phases of the circuit. See also peak value.

phase rotation—phase rotations refers to the order in which the instantaneous values of the voltages or currents of the system reach their maximum positive values. Two phase rotations are possible: A-B-C or A-C-B.

potential transformer (PT)—also known as a

voltage transformer

power factor (PF)—true power factor is the ratio of real power to apparent power using the complete harmonic content of real and apparent power. Calculated by dividing watts by volt amperes. Power factor is the difference between the total power your utility delivers and the portion of total power that does useful work. Power factor is the degree to which voltage and current to a load are out of phase. See also displacement power factor.

predicted demand—the circuit monitor takes into account the energy consumption thus far in the present interval and the present rate of consumption to predict demand power at the end of the present interval.

quantity—a parameter that the circuit monitor can measure or calculate such as current, voltage, power factor, etc.

real power—calculation of the real power (3-phase total and per-phase real power calculated) to obtain kilowatts.

recloser sequence—a series of voltage sags caused by a utility breaker opening a number of consecutive times in an effort to clear a fault. See also sag/swell.

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