12.6.5 SettingsTable 359:ECRWPSCH (85) Group settings (basic)Name Values (Range) Unit Step Default DescriptionCurrRev DisabledEnabled- - Disabled Operating mode of Current Reversal LogictPickUpRev 0.000 - 60.000 s 0.001 0.020 Pickup time for current reversal logictDelayRev 0.000 - 60.000 s 0.001 0.060 Time Delay to prevent Carrier send and localtripWEI DisabledEchoEcho & Trip- - Disabled Operating mode of WEI logictPickUpWEI 0.000 - 60.000 s 0.001 0.000 Coordination time for the WEI logic3V0PU 5 - 70 %VB 1 25 Neutral voltage setting for fault conditionsmeasurementTable 360:ECRWPSCH (85) Non group settings (basic)Name Values (Range) Unit Step Default DescriptionGlobalBaseSel 1 - 6 - 1 1 Selection of one of the Global Base Valuegroups12.6.6 Operation principle12.6.6.1 Directional comparison logic functionThe directional comparison function contains logic for blocking overreaching andpermissive overreaching schemes during current reversal.The circuits for the permissive overreaching scheme contain logic for current reversal andweak-end infeed functions. These functions are not required for the blocking scheme.Use the independent or inverse time functions in the directional ground-fault protectionmodule to get back-up tripping in case the communication equipment malfunctions andprevents operation of the directional comparison logic.Figure 249 and figure 250 show the logic circuits.12.6.6.2 Fault current reversal logicThe fault current reversal logic uses a reverse directed element, connected to the inputsignal IREV, which recognizes that the fault is in reverse direction. When the reversedirection element is activated the output signal IRVL is activated which is shown in1MRK 506 335-UUS A Section 12Scheme communication525Technical manual
