SEL-700G

Generator Protection Relay

1. Product Introduction The SEL-700G series provides comprehensive protection relay solutions for small, medium, and large generators. The lineup includes the SEL-700G0/G1 for basic to comprehensive protection, the SEL-700GT specialized for intertie protection, and the SEL-700GW for wind generators. It enhances system reliability and reduces complexity by integrating primary and backup generator protection with synchronization functions for safe grid connection.

Key Features

Comprehensive Generator Protection

Combines current, voltage, frequency, distance, power, and out-of-step elements to protect equipment from internal faults and external grid disturbances.
100% Stator Ground Protection

Utilizes neutral overvoltage elements to provide full-winding coverage for stator ground faults without blind spots.
Negative-Sequence Current Differential (87Q)

Provides high-sensitivity detection of low-magnitude faults using negative-sequence percentage-restrained differential elements.
Advanced Sensor Compatibility

Supports Low-Energy Analog (LEA) voltage sensors, Rogowski coils, and Low-Power Current Transformer (LPCT) inputs for flexible connection with modern primary equipment.
Intertie Protection

Offers islanding detection using Vector Shift and Rate of Change of Frequency (ROCOF) to safely disconnect the generator during grid events.
Automatic Synchronism Check and Synchronization (25A)

Built-in autosynchronizing functionality automatically matches voltage, frequency, and phase for up to two breakers to support safe grid connection.
Enhanced Breaker Failure Logic

Maximizes reliability with retrip logic, separate breaker failure trip logic, and settable breaker failure seal-in delay settings.

Color Touchscreen Display

The large 5-inch color screen (800x480 resolution) allows for intuitive local monitoring of synchroscopes, real-time metering data, and breaker control.
Embedded Web Server

Enables remote checking of relay status, settings, and event reports via a standard web browser, improving maintenance efficiency.
Communication Redundancy:

Supports Parallel Redundancy Protocol (PRP) and Rapid Spanning Tree Protocol (RSTP) to ensure seamless data transmission and fast network recovery during communication network failures.
Broad Protocol Support

Supports various industry-standard protocols, including IEC 61850 Edition 2, Modbus TCP/RTU, DNP3, EtherNet/IP, and IEEE C37.118-2005 (synchrophasors).
Precision Time Synchronization

Provides microsecond-level synchronization via IEEE 1588 PTP and IRIG-B inputs for accurate disturbance and event analysis.
Event Analysis and Recording

Records detailed data on generator startup, shutdown, and system faults using high-resolution event reports and Sequential Events Recorder (SER) functions.
Flexible Hardware Expansion

Slot-based architecture allows I/O and communication ports to be configured according to specific field requirements.