5.2 Configuring analog CT inputsThe analog input channels must be configured to get correct measurement results aswell as correct protection functionality. Because all protection algorithms in the IEDutilize the primary system quantities, it is extremely important to make sure thatconnected current transformer settings are done properly. These data are calculated bythe system engineer and normally set by the commissioner from the local HMI or fromPCM600.The analog inputs on the transformer input module are dimensioned for either 1A or5A. Each transformer input module has a unique combination of current and voltageinputs. Make sure the input current rating is correct and that it matches the orderdocumentation.The primary CT data are entered via the HMI menu under Main menu/Settings/General Settings/Analog modules/AnalogInputsThe following parameter shall be set for every current transformer connected to theIED:Table 8:CT configurationParameter description Parameter name Range DefaultRated CT primary current in A CT Prim Input from 0 to 99999 3000This parameter defines the primary rated current of the CT. For two set of CTs withratio 1000/1 and 1000/5 this parameter is set to the same value of 1000 for both CTinputs. The parameter CTStarPoint can be used in order to reverse the direction of theCT. This might be necessary if two sets of CTs have different star point locations inrelation to the protected busbar.For main CTs with 2A rated secondary current, it is recommended to connect thesecondary wiring to the 1A input.Take the rated permissive overload values for the current inputs intoconsideration.5.3 Reconfiguring the IEDI/O modules configured with PCM600 (BIM, BOM or IOM) are supervised.I/O modules that are not configured are not supervised.Section 5 1MRK 511 360-UEN AConfiguring the IED and changing settings54 Bay control REC670 2.1 IECCommissioning manual
