Functional Overview - Schweitzer Engineering Laboratories SEL-787-2 Manual

Functional Overview

3
3
52 52
Internal or External
RTD Input
1
52
3
3
Figure 1 SEL-787-3E Functional Diagram
Schweitzer Engineering Laboratories, Inc.
SEL-787-3E Transformer Protection Relay
Combined
Σ
P
51 51
Time-
G
Overcurrent
• Phase
• Ground
Temperature Alarm
and Trip
Restricted
REF REF
Earth Fault
Overcurrent
Directional • Phase
32 32
Power • Ground
• Neg-Seq
• Breaker Failure
O
24 24 81 81
U
Volts/Hertz Frequency
• Over
• Under
• Sequential Events Recorder
• Event Reports
• Web Server
• SEL, Ethernet*, Modbus RTU, Modbus TCP/IP*,
DNP3 serial*, DNP3 LAN/WAN*, FTP*, Telnet*, SNTP*,
IEEE 1588-2008 firmware-based PTP*, IEC 61850 Edition 2*,
IEC 60870-5-103*, EtherNet/IP*, PRP*, Event Messenger,
DeviceNet* Communications
• Synchrophasor Data and IEEE C37.118-2005 Compliant
Protocol
• Two Inputs and Three Outputs Standard
• I/O Expansion*--Additional Contact Inputs/Outputs, Analog
Inputs/Outputs, and RTD Inputs
• Single or Dual Ethernet Copper or Fiber-Optic
Communications Port*
Overcurrent Time-Overcurrent
• Phase • Phase
• Ground • Ground
• Neg-Seq • Neg-Seq
• Breaker Failure
Overcurrent Time-Overcurrent
• Phase • Phase
• Ground • Ground
• Neg-Seq • Neq-Seq
Current
• Breaker Failure
Differential
Overcurrent
Time-Overcurrent
Time-Overcurrent
• Phase
• Ground
• Neg-Seq
59 59
27P 27P 27I 27I
Undervoltage Inverse-Time Overvoltage
Undervoltage
• Phase
• Ground
• Neg-Seq
• Breaker Failure
• Battery-Backed Clock, IRIG-B Time Synchronization
• Instantaneous, Differential, Harmonic, and RMS
Metering
• Programmable Pushbuttons and LED Indicators
• Through-Fault Monitoring
• Transformer Thermal Monitoring
• Circuit Breaker Contact Wear Monitor
• Advanced SEL
• 32 Programmable Display Messages
• M B
IRRORED ITS
• Front-Panel Programmable Tricolor LED Targets
• Front-Panel HMI With 2 x 16-Character LCD
• 5-Inch, Color, 800 x 480-Pixel Touchscreen Display*
*
Optional Functions
87 87
LOP LOP
59I 59I
Inverse-Time Loss of Potential
Overvoltage
Control Equations
OGIC
Communications
SEL-787-2, -3, -4 Data Sheet
5