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Reactive Power Controller Operating instructions

Reactive Power Controller Operating instructions

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<strong>Reactive</strong> <strong>Power</strong> <strong>Controller</strong>Funktional descriptionMeasurementThe measurement is suited for 3 phase systems with orwithout neutral conductor for frequencies of 50Hz or60Hz. The electronical measurement system records anddigitalizes the effective values of voltage between L2and L3 (L-N Option) and the current in L1.In each second several snap check measurements arecarried out. As the current is only measured in oneouter conductor, and the voltage only between two outerconductors, the measured values, which are related toall three outer conductors, are exact for equal loadedouter conductors only.The following electrical quantities are calculated:Current and current harmonicsVoltage and voltage harmonicsReal power, sumApparent power,sum<strong>Reactive</strong> power, sum<strong>Reactive</strong> power for each stage<strong>Reactive</strong> current for each stageCos(phi),Net frequency.The following information can be indicated:Number of switchings of each stage,total connection time of each stage andthe inner temperature.Prophi measures the frequency of the measurement andsupply voltage and shows the average over 10 seconds.Switching of capacitor stagesProphi calculates the required reactive power to reachthe set target-cos(phi) from the current from one outerconductor and the voltage between two outer conductors.If the cos(phi) deviates from target cos(phi), externalcapacitor stages or transistor outputs are switchedon or off.In automatic mode the capacitor stages are switched inor off, when the required reactive power is higher orequal to the smallest stage power.If the power of the first capacitor stage is three times ashigh as the measured real power, all capacitor stagesare switched off.Switching outputsDepending on the variety of Prophi, relay or transistoroutputs serve as switching outputs.The relay outputs are suitable for controlling contactorsand the transistor outputs can switch thyristor modules,that switch in zero crossing of voltage.For relay outputs the time between two connections ordisconnections is set to two seconds. Transistor outputshave no limitation of the switching period.Net returnAfter net return, the set discharge time runs for therelay outputs. The transistor outputs do not mention thedischarge time.Page 6= Key 1 = Key 2 = Key 3

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