Schweitzer Engineering Laboratories SEL-351 - Section 5: Trip and Target Logic

Date Code 20001006 Trip and Target Logic i
SEL-351 Instruction Manual
TABLE OF CONTENTS
SECTION 5: TRIP AND TARGET LOGIC................................................. 5-1
Trip Logic................................................................................................................................5-1
Set Trip ............................................................................................................................5-3
Unlatch Trip .....................................................................................................................5-4
Other Applications for the Target Reset Function.......................................................5-5
Factory Settings Example (Using Setting TR)....................................................................5-5
Set Trip.....................................................................................................................5-5
Unlatch Trip..............................................................................................................5-6
Additional Settings Examples............................................................................................5-6
Unlatch Trip with 52a Circuit Breaker Auxiliary Contact...........................................5-6
Unlatch Trip With 52b Circuit Breaker Auxiliary Contact..........................................5-6
Program an Output Contact for Tripping...........................................................................5-7
Switch-Onto-Fault (SOTF) Trip Logic......................................................................................5-7
Three-Pole Open Logic .....................................................................................................5-8
Determining Three-Pole Open Condition Without Circuit Breaker Auxiliary
Contact..............................................................................................................5-9
Circuit Breaker Operated Switch-Onto-Fault Logic ...........................................................5-9
Close Bus Operated Switch-Onto-Fault Logic....................................................................5-9
Switch-Onto-Fault Logic Output (SOTFE)......................................................................5-10
Switch-Onto-Fault Trip Logic Trip Setting (TRSOTF)....................................................5-10
Communications-Assisted Trip Logic – General Overview ......................................................5-11
Enable Setting ECOMM .................................................................................................5-11
Trip Setting TRCOMM ..................................................................................................5-12
Trip Settings TRSOTF and TR.......................................................................................5-12
Trip Setting DTT............................................................................................................5-13
Use Existing SEL-321 Relay Application Guides for the SEL-351 Relay .........................5-13
Optoisolated Input Settings Differences Between the SEL-321 and
SEL-351 Relays...............................................................................................5-13
Trip Settings Differences Between the SEL-321 and SEL-351 Relays.......................5-14
Permissive Overreaching Transfer Trip (POTT) Logic............................................................5-14
Use Existing SEL-321 Relay POTT Application Guide for the SEL-351 Relay................5-14
External Inputs ...............................................................................................................5-14
PT1 – Received Permissive Trip Signal(s)................................................................5-15
Timer Settings.................................................................................................................5-15
Z3RBD – Zone (Level) 3 Reverse Block Delay ........................................................5-15
EBLKD – Echo Block Delay ...................................................................................5-16
ETDPU – Echo Time Delay Pickup.........................................................................5-16
EDURD – Echo Duration........................................................................................5-16
Logic Outputs.................................................................................................................5-16
Z3RB – Zone (Level) 3 Reverse Block.....................................................................5-16
ECTT – Echo Conversion to Trip ............................................................................5-16
KEY – Key Permissive Trip ....................................................................................5-16
EKEY – Echo Key Permissive Trip .........................................................................5-16
Variations for Permissive Underreaching Transfer Trip (PUTT) Scheme..........................5-18
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