P12x/EN T/Eb6 - Schneider - error

Application GuideP12x/EN AP/Eb6MiCOM P120/P121/P122/P123 Page 35/7813. SWITCH ON TO FAULT / TRIP ON RECLOSE PROTECTION (P123 ONLY)13.1 GeneralIn some feeder applications, fast tripping may be required if a fault is still present on thefeeder after the reclose of the circuit breaker (Close on to fault).Some faults may not be cleared after a reclose due to the fact that the conditions that led tothe fault have not been removed from the feeder after a reclosing cycle or a manual trip, ordue to earthing clamps left on after a maintenance visit. In these cases, it may be desirableto clear the fault condition in a quicker time, rather than to wait for the trip delay time DMT orIDMT associated with the involved protection to elapse.In the case of a CB being manually closed, a switch on to an existing fault may occur. Thissituation is particularly critical because the overcurrent protection would not clear the faultuntil the set time delay has elapsed. It is then desirable to clear the fault as fast as possible.Activation and setting of the SOTF/TOR (Switch On To Fault/ Trip On Reclose) function canbe done under the AUTOMATIC CTRL/SOTF submenu.The crossing of I>> and I>>> thresholds initiate the SOTF function.13.2 SOTF/ TOR descriptionThe following signals can activate the SOTF/TOR function:- “Ctrl close” logical input,- manual closing ordered by HMI,- command generated by a digital input labelled “SOTF”,- front communication order,- rear communication order,- close ordered by autorecloser,The following diagram illustrates this functionality.AutorecloserAR selected00&0I>>AutorecloserI>>>Rear Com orderRear Com selectedFront Com order000&&00&t SOTF0..500 msvalided bysettingFront Com selected0ORMonostable500 msCtrl Close inputCtrl Close slected00&0ORTripSOTF (Manualclose) input dSOTF (Manual close)input selected00&0tI> valided bysettingHMI order0&0tI>> valided bysettingHMI order selected0tI>>> valided bysettingClose origin: Signalling of the circuit breaker closing requestSOTF setting: Setting : Choice of the SOTF feature activationSOTF settingTrip setting: Threshold type selected in SOTF setting: Threshold type selected in Trip settingP3939ENaFIGURE 11: LOGIC DIAGRAM OF THE SOTF