SEL-700G
Generator Protection Relay
The SEL-700G Relay is the right solution for utility and industrial generator protection, with an autosynchronizer, flexible I/O, and advanced communications. Apply the SEL-700G Relay for comprehensive primary and backup generator protection.
The SEL-700G provides a complete protection and synchronization solution for synchronous generators. Eliminate the complexity and cost of standalone synchronizer packages. Integrating the synchronization capability into the generator protection relay provides the most cost-effective and reliable solution. Easily upgrade protection without cutting or drilling existing cutouts with a small form factor and multiple mounting adapters. Quickly integrate into serial- or Ethernet-based communications with Modbus, DNP3, IEC 61850, Mirrored Bits communications, DeviceNet, and other protocols.
Major Features and Benefits
The SEL-700G family of protection relays provides unsurpassed protection, integration, and control features in a
flexible, compact, and cost-effective package.
➤ Basic Generator Protection Features (SEL-700G0): Ground differential; sensitive restricted earth fault;
thermal overload; phase, negative-sequence, residual-ground, and neutral-ground overcurrent elements for
backup; residual-ground and neutral-ground time-overcurrent elements; directional residual-ground and neutralground
overcurrent elements; current unbalance element; voltage-controlled, voltage-restrained time-overcurrent
element for backup protection; breaker failure protection for three-pole breaker; under- and overvoltage
elements; loss-of-potential element; volts/hertz or overexcitation protection; directional power elements; loss-offield;
over- and underfrequency protection elements; off-frequency time accumulators; rate-of-change-offrequency
elements; inadvertent energization protection; RTD protection (requires internal or external SEL-2600
RTD option); field ground using an SEL-2664 Field Ground Module.
➤ Optional Generator Protection Features (SEL-700G0+, SEL-700G1, SEL-700G1+): Generator synchronismcheck
elements; synchronism-check under- and overvoltage elements; autosynchronism; backup compensator
distance elements; out-of-step elements; 100% stator ground protection elements; and dual-slope current differential
protection with harmonic blocking and restraint elements to provide sensitive and secure protection. The
high-security mode provides additional security against CT saturation during external events including external
transformer energization, external faults, etc.
➤ Intertie Protection Features (SEL-700GT): Phase, negative-sequence, and residual-ground overcurrent
elements; phase, negative-sequence, and residual-ground time-overcurrent elements; phase, negative-sequence
and residual-ground directional overcurrent elements; breaker failure protection for three-pole breaker; underand
overvoltage elements; loss-of-potential element; directional power elements; over- and underfrequency
SEL-700G0, SEL-700G1 SEL-700GT SEL-700GW
Basic to Comprehensive
Protection Intertie Protection Basic Dual-Feeder
Overcurrent Protection
Small, Medium, and
Large Generators Intertie and Generator Wind Generator
SEL-700G Family of Generator and
Intertie Protection Relays
SEL-700G Data Sheet Schweitzer Engineering Laboratories, Inc.
2
protection elements; rate-of-change-of-frequency elements; tie synchronism-check elements; synchronism-check under
and overvoltage elements; autosynchronism; and RTD protection (requires internal or external SEL-2600 RTD option).
➤ Optional Intertie Protection Features (SEL-700GT+). Addition of basic generator protection features, as
shown above for the SEL-700G0, to create intertie and generator protection. The relay also includes generator
synchronism-check and autosynchronism functions.
➤ Wind Generator Protection Features (SEL-700GW). The SEL-700GW is configured with two sets of phase,
negative-sequence, and residual-ground overcurrent elements, and phase, negative-sequence, and residual-ground
time-overcurrent elements to provide dual-feeder protection in a multiwind generator network application. The relay also
includes three-pole breaker failure protection for two breakers.
➤ Generator Monitoring. Monitor ambient and generator winding temperature using optional analog inputs or
RTDs and protect the generator from thermal damage. Use off-frequency time accumulators and protect steam
turbine blades from fatigue failures because of off-frequency vibration.
➤ Operator Controls. Four programmable front-panel pushbuttons each with two programmable LEDs allow for a
wide variety of uses, including easy trip and close control and status indications for a breaker. Implement local
and remote operator control schemes using 32 local and 32 remote control bits.
➤ Relay and Logic Settings Software. ACSELERATOR QuickSet® SEL-5030 Software reduces engineering costs
for relay settings and logic programming. The tools in ACSELERATOR QuickSet make it easy to develop
SELOGIC® control equations. Use the built-in phasor display to verify proper CT polarity and phasing. Use the
synchroscope to watch the autosynchronism controls.
➤ Metering and Reporting. Built-in metering functions eliminate separately mounted metering devices. Analyze
Sequential Events Recorder (SER) reports and oscillographic event reports for rapid commissioning, testing, and
post-fault diagnostics. Unsolicited SER protocol allows station-wide collection of binary SER messages.
➤ Additional Standard Features. Includes Modbus® RTU, Event Messenger support, MIRRORED BITS® communications,
load profile report, support for 12 external RTDs (SEL-2600 module), IRIG-B input, advanced
SELOGIC, configurable labels, IEEE C37.118-compliant synchrophasor protocol, and fiber-optic serial port.
➤ Optional Features. Select from a wide offering of optional features, including SNTP (Simple Network Time
Protocol), IEC 61850, Modbus® TCP/IP, DNP3 LAN/WAN, DNP3 Serial, 10 internal RTDs, expanded digital/
analog I/O, voltage/current inputs, additional EIA-232 or EIA-485 communications ports, and single or dual,
copper wire or fiber-optic Ethernet ports.
