Standard Feature Model Optionƒ Function
| Features | SEL-551 SEL-551C | SEL-851 | SEL-751 |
|---|---|---|---|
| Display/Front Panel | |||
| Color Touchscreen | |||
| Graphical LCD Display | |||
| Local/Remote Control | |||
| Trip/Close Breaker Control | |||
| 8 Programable LEDs | |||
| USB-C Communications Port | |||
| CT/PT Inputs | |||
| 1 A/5 A Software-Selectable Current Inputs | |||
| Voltage Inputs | |||
| Applications | |||
| Breaker Failure Protection | ƒ | ||
| Underfrequency Load Shedding | |||
| Undervoltage Load Shedding | |||
| Loss-of-Potential Logic | |||
| Protection Elements | |||
| 50AF/50NAF Arc-Flash Detection Instantaneous Overcurrent | |||
| 27/59 Over-/Undervoltage | |||
| 32 Directional Power | |||
| 50 (P,N,G,Q) Overcurrent (Phase, Neutral, Ground, Neg. Seq.) | |||
| 51 (P,N,G,Q) Time-Overcurrent (Phase, Neutral, Ground, Neg. Seq.) | |||
| 55 Power Factor | |||
| 60 Loss-of-Potential | |||
| 67 Directional Overcurrent | |||
| 81O/81U Over-/Underfrequency | |||
| 81R Rate-of-Change of Frequency | |||
| Second-Harmonic Blocking | |||
| Instrumentation and Control | |||
| Arc-Flash Detection Inputs | |||
| Load/Signal Profile Recorder | |||
| Software-Invertible Polarities | |||
| Built-In Web Server | |||
| Harmonic Metering | |||
| RMS Metering | |||
| Synchrophasors | |||
| Configuration Software | acSELerator QuickSet SEL-5030 Software | SEL Grid Configurator Software | acSELerator QuickSet SEL-5030 Software |
| Programmable Digital Inputs (24–250 Vdc/Vac) | |||
| Low-Energy Analog (LEA) Inputs | |||
| Universal Power Supply (24–250 Vdc/110–240 Vac) | |||
| Communications Ports and Protocols | |||
| USB-C Port (Front) | |||
| Settings-Selectable EIA-232/EIA-485 Port (Rear) | |||
| Single 10/100BASE-T Ethernet Port (Rear) | |||
| Dual 10/100BASE-T Ethernet Ports (Rear) | |||
| Modbus RTU and Modbus TCP/IP | |||
| IEC 61850 Edition 2.1 | |||
| IEC 61850 Edition 2 | |||
| DNP3 Level 2 (Serial and LAN/WAN) | |||
| Simple Network Time Protocol (SNTP) | |||
This table lists key features but is not comprehensive. For detailed information on each relay, visit the product pages: