Schweitzer Engineering Laboratories SEL-751 - Page 887

K.17
Date Code 20170927 Instruction Manual SEL-751 Relay
Relay Word Bits
Definitions
LB25–LB32 Local bits 25–32
42
LBOKA Channel A, looped back ok
96
LBOKB Channel B, looped back ok
96
LINK1 Asserted when a valid link is detected on Port 1
145
LINKA Asserts when Ethernet Port 1A detects link
13
LINKB Asserts when Ethernet Port 1B detects link
13
LINKFAIL Failure of active Ethernet port link
31
LOCAL Asserts when relay control configuration is in LOCAL mode
151
LOP Loss-of-potential
14
LPSEC Direction of the upcoming leap second. During the time that LPSECP is asserted, if LPSEC is
asserted, the upcoming leap second is deleted; otherwise, the leap second is added.
116
LPSECP Leap second pending
116
LR3 Three-phase load reduction event
139
LRA A-phase load reduction in
139
LRB B-phase load reduction in
139
LRC C-phase load reduction in
139
LT01–LT08 Latch bits 1–8
55
LT09–LT16 Latch bits 9–16
56
LT17–LT24 Latch bits 17–24
57
LT25–LT32 Latch bits 25–32
58
LZFWD Zero-sequence voltage-polarized forward direction detected low impedance controls
151
LZREV Zero-sequence voltage-polarized reverse direction detected low impedance controls
151
MATHERR SEL
OGIC math error bit asserted for divide-by-zero, etc., in SELOGIC math functions
145
N1DIR Directional control for elements 67N1P, 51N1P, 51N2P
149
N2DIR Directional control for element 67N2P
149
N3DIR Directional control for element 67N3P
149
N4DIR Directional control for element 67N4P
149
NSA A-phase fault identification logic output. Used in fault-type target logic for Petersen coil-
grounded and ungrounded/high-impedance grounded systems.
152
NSB B-phase fault identification logic output. Used in fault-type target logic for Petersen coil-
grounded and ungrounded/high-impedance grounded systems.
152
NSC C-phase fault identification logic output. Used in fault-type target logic for Petersen coil-
grounded and ungrounded/high-impedance grounded systems.
152
NTUNE_A A-phase normal tuning
135
NTUNE_B B-phase normal tuning
135
NTUNE_C C-phase normal tuning
135
OC Open command
33
Table K.2 Relay Word Bit Definitions for the SEL-751 Relay (Sheet 12 of 17)
Bit Definition Row