4.2.1.1 Example SEMOD55055-11 v4Usually 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 channel numberdepends 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 channels SEMOD55055-16 v5The direction of a current to the IED is depending on the connection of the CT. Unless indicatedotherwise, the main CTs are supposed to be Wye (star) connected and can be connected with thegrounding point to the object or from the object. This information must be set in the IED. Theconvention of the directionality is defined as follows: A positive value of current, power, and so onmeans that the quantity has the direction into the object and a negative value means direction outfrom the object. For directional functions the direction into the object is defined as Forward andthe direction out from the object is defined as Reverse. See figure 18A positive value of current, power, and so on (forward) means that the quantity has a directiontowards the object. - A negative value of current, power, and so on (reverse) means a directionaway from the object. See figure 18.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 EN-USFigure 18: Internal convention of the directionality in the IEDWith correct setting of the primary CT direction,CT_WyePoint set toFromObject orToObject, apositive quantities always flowing towards the object and a direction defined as Forward always islooking towards the object. The following examples show the principle.4.2.2.1 Example 1 SEMOD55055-23 v5Two IEDs used for protection of two objects.Section 4 1MRK 511 358-UUS AAnalog inputs68Application manual
