Sel 411L - Figure 3.47 87 LP Logic in Applications with In-Line Transformers

P.3.91
Date Code 20151029 Protection Manual SEL-411L Relay
Protection Functions
87L Differential Elements
Figure 3.47 87LP Logic in Applications With In-Line Transformers
RAD BA
k
AP
Alpha Plane
Comparator
(Harmonic Blocking)
Analogs
87K
Φ
A
87LPR
87LPRS
0
1
87LPA
87LPAS
0
1
87LPP
87LPPS
0
1
Relay Word Bit
87DD
Relay Word Bit
87L
Φ
ID PKP
OC
Relay Word Bit 87L5O
Φ
Relay Word Bit
87LPSEC
Analog
(to trip logic)
2 cyc
0
Test point
87TEST
87BLK
87APAΦ
Relay Word Bits
87MTR
(to test mode logic)
Relay Word Bit
87LP
Relay Word Bits
87LA 87LB 87LC
ID PKP
OC
Relay Word Bit 87LU
Φ
Setting
87LPU
Relay Word Bit
87LU
Relay Word Bits
87LUA 87LUB 87LUC
RAD BA
k
AP
A
Analogs
Relay Word Bit 87HB
Φ
Relay Word Bit 87HR
Φ
E87XFMR = Y
Φ = A, B, C
87I
ΦFM
Settings
Alpha Plane
Comparator
(Harmonic Restraint)
Overcurrent
Comparator
(High-set)
Overcurrent
Comparator
(Supervision)
87KHRΦ
87HRAΦ