4.2.1.1 ExampleUsually the A phase-to-ground voltage connected to the first VT channel number of thetransformer input module (TRM) is selected as the phase reference. The first VT channelnumber depends on the type of transformer input module.For a TRM with 6 current and 6 voltage inputs the first VT channel is 7. The settingPhaseAngleRef=7 shall be used if the phase reference voltage is connected to that channel.4.2.2 Setting of current channelsThe direction of a current to the IED is depending on the connection of the CT. Unlessindicated otherwise, the main CTs are supposed to be Wye (star) connected and can beconnected with the grounding point to the object or from the object. This information mustbe set in the IED. The convention of the directionality is defined as follows: A positivevalue of current, power, and so on means that the quantity has the direction into the objectand a negative value means direction out from the object. For directional functions thedirection into the object is defined as Forward and the direction out from the object isdefined as Reverse. See figure 14A positive value of current, power, and so on (forward) means that the quantity has adirection towards the object. - A negative value of current, power, and so on (reverse)means a direction away from the object. See figure 14.Protected ObjectLine, transformer, etcForwardReverseDefinition of directionfor directional functionsMeasured quantity ispositive when flowingtowards the objecte.g. P, Q, IReverseForwardDefinition of directionfor directional functionse.g. P, Q, IMeasured quantity ispositive when flowingtowards the objectSet parameterCTStarPointCorrect Setting is"ToObject"Set parameterCTStarPointCorrect Setting is"FromObject"en05000456-2.vsdANSI05000456 V2 ENFigure 14: Internal convention of the directionality in the IEDWith correct setting of the primary CT direction, CT_WyePoint set to FromObject orToObject, a positive quantities always flowing towards the object and a direction definedas Forward always is looking towards the object. The following examples show theprinciple.Section 4 1MRK 505 337-UUS -Analog inputs62Application manual
