Schweitzer Engineering Laboratories SEL-421-4 - Page 646

11.30
SEL-421 Relay Instruction Manual Date Code 20171021
Relay Word Bits
Alphabetical List
TSNTPB Asserts if time was synchronized with backup NTP server before SNTP timeout period expired 209
TSNTPP Asserts if time was synchronized with primary NTP server before SNTP timeout period expired 209
TSOK Assert if current time source accuracy is sufficient for synchronized phasor measurements 209
TSSW High-priority time source switching 210
TSYNC Assert when ADC sampling is synchronized to an IRIG-B time source 210
TSYNCA Assert while the time mark from time source or fixed internal source is not synchronized 209
TUPDH Assert if update source is high-accuracy time source 209
TUTC1 IRIG-B Offset hours from UTC time, binary, add 1 if asserted 293
TUTC2 IRIG-B Offset hours from UTC time, binary, add 2 if asserted 293
TUTC4 IRIG-B Offset hours from UTC time, binary, add 4 if asserted 293
TUTC8 IRIG-B Offset hours from UTC time, binary, add 8 if asserted 293
TUTCH IRIG-B Offset half-hour from UTC time, binary, add 0.5 if asserted 293
TUTCS IRIG-B Offset hours sign from UTC time, subtract the UTC offset if TUTCS is asserted, add otherwise 293
UBB Block permissive trip Receiver 1 or 2 59
UBB1 Blocks permissive trip Receiver 1 59
UBB2 Blocks permissive trip Receiver 2 59
UBOSB Unblock out-of-step blocking 21
ULCL1 Unlatch closing for Circuit Breaker 1 (SEL
OGIC control equation) 46
ULCL2 Unlatch closing for Circuit Breaker 2 (SEL
OGIC control equation) 46
ULMTR1 Circuit Breaker 1 unlatch manual trip 56
ULMTR2 Circuit Breaker 2 unlatch manual trip 56
ULTR Unlatch all protection trips 56
ULTRA Unlatch Trip A 57
ULTRB Unlatch Trip B 57
ULTRC Unlatch Trip C 57
UPD_BLK Block updating internal clock period and Master Time 212
UPD_EN Enable updating internal clock with selected external time source 209
VB001–VB008 Virtual Bit 001–008 263
VB009–VB016 Virtual Bit 009–016 262
VB017–VB024 Virtual Bit 017–024 261
VB025–VB032 Virtual Bit 025–032 260
VB033–VB040 Virtual Bit 033–040 259
VB041–VB048 Virtual Bit 041–048 258
VB049–VB056 Virtual Bit 049–056 257
VB057–VB064 Virtual Bit 057–064 256
VB065–VB072 Virtual Bit 065–072 255
VB073–VB080 Virtual Bit 073–080 254
VB081–VB088 Virtual Bit 081–088 253
VB089–VB096 Virtual Bit 089–096 252
VB097–VB104 Virtual Bit 097–104 251
VB105–VB112 Virtual Bit 105–112 250
Table 11.1 Alphabetic List of Relay Word Bits (Sheet 30 of 34)
Name Description Row