SEL-451 Data Sheet
Schweitzer Engineering Laboratories, Inc.
4
Product Overview
Protection Features
Software-Invertible Polarities
Save Commissioning Time and
Costs
The SEL-451 provides software-invertible CT and PT
polarities. You can invert individual phase CT and PT
inputs to account for field wiring or invert whole CT ter-
minals to change a relay zone of protection without hav-
ing to change field wiring.
All signal processing uses the software-inverted polari-
ties for CEV file generation, metering, and protection
logic. COMTRADE file generation is isolated from the
impacts of the inverted polarities, and records signals as
applied to the relay terminals.
Directional Elements Increase
Sensitivity and Security
The SEL-451 provides multiple directional elements to
optimize security and sensitivity. Use ground and nega-
tive-sequence directional overcurrent elements to detect
high-resistance faults when using communications-
assisted tripping schemes.
The SEL-451 includes a number of directional elements
for supervision of overcurrent elements. The negative-
sequence directional element uses the same patented
principle proven in our SEL-351 Relay. This directional
element can be applied in virtually any application,
regardless of the amount of negative-sequence voltage
available at the relay location.
Figure 2
Product Overview
PROTECTION
AUTOMATION
BAY CONTROL
• Synchrophasors
• Directional Overcurrent (67)
• Dual Circuit Breaker Failure (50 BF)
• Synchronism Check (25)
• Instantaneous Overcurrent (50)
• Time Overcurrent (51)
• Over/Undervoltage (27/59)
• Over/Underpower (32)
• Frequency (81)
• Reclosing (79)
• Expanded SEL
OGIC
Control Equations
• Event Reports and Oscillography
• Sequential Events Recorder (SER)
• Dual Breaker Condition Monitor
• Station Battery Monitor
• Fault Locator
• Load-Encroachment Supervision
• TiDL Remote Data Acquisition
• Ethernet Communications Protocols
IEC 61850 Edition 2
DNP3 LAN/WAN
FTP
Telnet
PRP
PTP
C37.118 Synchrophasors
• Ethernet Media Options
10/100BASE-T Twisted Pair Network
100BASE-FX Fiber-Optic Network
• Serial Communications Protocols
SEL ASCII Commands
SEL M
IRRORED
B
ITS
Communications
SEL Fast Messages
DNP3
IEEE C37.118 Synchrophasors V7.3
• Password Separation of Automation and
Protection
• Configurable Bay Screen Display
• Local Control—As many as Two Breakers
• Status Indication—As many as
Three Breakers
• Local Control and Status Indication—As
many as 20 Disconnect Switches
• Bay Screen Displays—As many as
24 Analog Quantities
• Configurable Labels for Bus, Breakers,
Disconnect Switches, and Bay
• Password-Protected Control Functions
• Local and Remote Modes
• Control Confirmation Request
• Operation Alarm for Breaker and
Disconnect Switch
• As many as 10 individual one-line
diagrams available to HMI
Bus
Bus
Line
50BF
67
50
51
79
25
3
1
3
1
3
81
27
59
52
52
Wide Area Network
Router
Hub or Switch
Remote
Monitoring
and Control
Local
Control
and Status
PTP
SEL-2488 Satellite-Synchronized
Network Clock
93820
93830
BK2
BK1
SW1
SW2
SW3
SW4
SW5
P: 10.4 MW
I: 430 A
Q: 1.2 MVAR
F: 60.1 HZ
SEL-451
SEL-2488
