Table 247:ECRWPSCH Non group settings (basic)Name Values (Range) Unit Step Default DescriptionGlobalBaseSel 1 - 12 - 1 1 Selection of one of the Global BaseValue groups13.5.6 Operation principle13.5.6.1 Directional comparison logic function M13929-4 v6The directional comparison function contains logic for blocking overreaching andpermissive overreaching schemes.The circuits for the permissive overreaching scheme contain logic for currentreversal and weak-end infeed functions. These functions are not required for theblocking overreaching scheme.Use the independent or inverse time functions in the directional earth faultprotection module to get backup tripping in case the communication equipmentmalfunctions and prevents operation of the directional comparison logic.Connect the necessary signal from the autorecloser for blocking of the directionalcomparison scheme, during a single-phase autoreclosing cycle, to the BLOCKinput of the directional comparison module.13.5.6.2 Fault current reversal logic M13929-11 v8The fault current reversal logic uses a reverse directed element, connected to theinput signal IRV, which recognizes that the fault is in reverse direction. When thereverse direction element is activated the output signal IRVL is activated which isshown in Figure 211. The logic is now ready to handle a current reversal withouttripping. The output signal IRVL will be connected to the block input on thepermissive overreaching scheme.When the fault current is reversed on the healthy line, IRV is deactivated andIRVBLK is activated. The tDelayRev timer delays the reset of the output signal.The signal blocks operation of the overreach permissive scheme for residualcurrent and thus prevents unwanted operation caused by fault current reversal.Section 13 1MRK 505 394-UEN AScheme communication426 Line differential protection RED650 2.2 IECTechnical manual
