• Three-pole tripping for all fault types (3ph operating mode)• Single-pole tripping for single-pole faults and three-pole tripping for multiphase andevolving faults (1ph/3ph operating mode). The logic also issues a three-pole trippingcommand when phase selection within the operating protection functions is notpossible, or when external conditions request three-pole tripping.The three-pole trip for all faults offers a simple solution and is often sufficient in meshedtransmission systems and in High Voltage (HV) systems. Since most faults, especially atthe highest voltage levels, are single pole to ground faults, single pole tripping can be ofgreat value. If only the faulty pole is tripped, power can still be transferred on the lineduring the dead time that arises before reclosing. Single pole tripping during single phasefaults must be combined with single pole reclosing.13.2.2.1 Single- and/or three-pole trippingThe single-/three-pole tripping will give single-pole tripping for single-phase faults andthree-pole tripping for multi-phase fault. The operating mode is always used together witha single-phase autoreclosing scheme.The single-pole tripping can include different options and the use of the different inputsin the function block.The inputs 1PTRZ and 1PTREF are used for single-pole tripping for distance protectionand directional ground fault protection as required.The inputs are combined with the phase selection logic and the pickup signals from thephase selector must be connected to the inputs PS_A, PS_B and PS_C to achieve thetripping on the respective single-pole trip outputs TR_A, TR_B and TR_C. The OutputTRIP is a general trip and activated independent of which phase is involved. Dependingon which phases are involved the outputs TR1P, TR2P and TR3P will be activated as well.When single-pole tripping schemes are used a single-phase autoreclosing attempt isexpected to follow. For cases where the autoreclosing is not in service or will not followfor some reason, the input Prepare Three-pole Trip P3PTR must be activated. This isnormally connected to the respective output on the Auto- Recloser but can also beconnected to other signals, for example an external logic signal.If two breakers areinvolved, one TR block instance and one Auto-Recloser instance is used for each breaker.This will ensure correct operation and behavior of each breaker.The output Trip 3 Phase TR3P must be connected to the respective input in SESRSYN(25) to switch SESRSYN (25) to three-phase reclosing. If this signal is not activatedSESRSYN (25) will use single-phase reclosing dead time.Section 13 1MRK 506 334-UUS ALogic416Application manual
