Schweitzer Engineering Laboratories SEL-351 - Page 184

ii Trip and Target Logic Date Code 20001006
SEL-351 Instruction Manual
Installation Variations.....................................................................................................5-18
Directional Comparison Unblocking (DCUB) Logic................................................................5-19
Use Existing SEL-321 Relay DCUB Application Guide for the SEL-351 Relay ...............5-20
External Inputs ...............................................................................................................5-20
PT1, PT2 – Received Permissive Trip Signal(s).......................................................5-20
LOG1, LOG2 – Loss-of-Guard Signal(s).................................................................5-20
Timer Settings.................................................................................................................5-21
GARD1D – Guard-Present Delay............................................................................5-21
UBDURD – DCUB Disable Delay...........................................................................5-21
UBEND – DCUB Duration Delay ...........................................................................5-21
Logic Outputs.................................................................................................................5-21
UBB1, UBB2 – Unblocking Block Output(s) ...........................................................5-21
PTRX1, PTRX2 – Permissive Trip Receive Outputs................................................5-23
Installation Variations.....................................................................................................5-23
Directional Comparison Blocking (DCB) Logic.......................................................................5-24
Use Existing SEL-321 Relay DCB Application Guide for the SEL-351 Relay..................5-24
External Inputs ...............................................................................................................5-24
BT – Received Block Trip Signal(s).........................................................................5-25
Timer Settings.................................................................................................................5-25
Z3XPU – Zone (Level) 3 Reverse Pickup Time Delay..............................................5-25
Z3XD – Zone (Level) 3 Reverse Dropout Extension.................................................5-25
BTXD – Block Trip Receive Extension....................................................................5-25
67P2SD, 67N2SD, 67G2SD, 67Q2SD – Level 2 Short Delay..................................5-25
Logic Outputs.................................................................................................................5-25
DSTRT – Directional Carrier Start..........................................................................5-26
NSTRT – Nondirectional Carrier Start ....................................................................5-26
STOP – Stop Carrier...............................................................................................5-26
BTX – Block Trip Extension ...................................................................................5-26
Installation Variations.....................................................................................................5-27
Front-Panel Target LEDs........................................................................................................5-29
Additional Target LED Information.................................................................................5-30
TRIP Target LED ...................................................................................................5-30
INST Target LED ...................................................................................................5-30
COMM Target LED................................................................................................5-30
Another Application for the COMM Target LED .............................................5-30
SOTF Target LED ..................................................................................................5-31
50 Target LED........................................................................................................5-31
51 Target LED........................................................................................................5-31
81 Target LED........................................................................................................5-31
FAULT TYPE Target LEDs....................................................................................5-31
A, B, and C Target LEDs.................................................................................5-31
G Target LED..................................................................................................5-31
N Target LED..................................................................................................5-32
79 Target LEDs.......................................................................................................5-32
Target Reset/Lamp Test Front-Panel Pushbutton.............................................................5-32
Other Applications for the Target Reset Function.....................................................5-32
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