Title: DOCA0005EN-12.pdf
Apparent power (S) is the vector sum of real power (P) and reactive power (Q):S=P2 + Q2Real power is measured in watts (W or kW), reactive power is measured in vars (VAR or kVAR) and apparent power is measured in volt-amps (VA or kVA).Power and the PQ coordinate systemThe meter uses the values of real power (P) and reactive power (Q) on the PQ coordinate system to calculate apparent power.+Q (+kVAR)Quadrant 2Quadrant 1)+(QSS)+(QP (-)P (+)P (-kW)+P (+kW)P (-)P (+)Q (-)SSQ (-)Quadrant 3Quadrant 4Q (-kVAR)Power flowPositive power flow P(+) and Q(+) means power is flowing from the power source towards the load. Negative power flow P(-) and Q(-) means power is flowing from the load towards the power source.DOCA0005EN-12127Power, energy and power factoriEM3000 series user manualEnergy delivered (imported) / energy received (exported)