Schweitzer Engineering Laboratories SEL-751 - Page 39

1.3
Date Code 20170927 Instruction Manual SEL-751 Relay
Introduction and Specifications
Features
67N Neutral Overcurrent With
Directional Control
X
b
51mP Phase Time Overcurrent
(m =A,B,C)
XXX
51P Max. Phase Time Overcurrent X X X
51P Max. Phase Time Overcurrent With
Directional Control
X
a
X
b
51G Residual Time Overcurrent X X X
51G Residual Time Overcurrent With
Directional Control
X
a
X
b
51Q Neg.-Seq. Time Overcurrent X X X
51Q Neg.-Seq. Time Overcurrent With
Directional Control
X
a
X
b
51N Neutral Time Overcurrent X X X
51N Neutral Time Overcurrent With
Directional Control
X
b
SEF Sensitive Earth Fault X
HBL Second- and Fifth-Harmonic
Blocking
XXX
FLOC Fault Locator X X
27 Undervoltage
(Phase, Phase-to-Phase, Vsync)
XX
59 Overvoltage (Phase,
Phase-to-Phase, Seq., Vsync)
XX
27I Inverse Time Undervoltage (Phase,
Phase-to-Phase, Seq., Vsync)
XX
59I Inverse Time Overvoltage (Phase,
Phase-to-Phase, Seq., Vsync)
XX
60LOP Loss of Potential X X
32 Directional Power X X
49T IEC Thermal (line/cable) X X X
55 Power Factor X X
78VS Vector Shift X X
81 Over- and Underfrequency X X X
81R Rate-of-Change of Frequency X X
81RF Fast Rate-of-Change of Frequency X X
25 Synchronism Check X X
BF Breaker Failure X X X
49RTD RTDs X
c
X
c
X
c
79 Reclosing X
c
X
c
X
c
Table 1.3 SEL-751 Protection Elements (Sheet 2 of 3)
Protection Element
Slot Z 4 ACI/3 AVI
Card With 1 A or 5 A
Neutral Channel
Slot Z 4 ACI/3 AVI
Card With 200 mA
Neutral Channel
Slot Z 4 ACI Card
(Current Only Model)
With 1 A or 5 A
Neutral Channel