GE SR745-W2-P5-G5-HI-A Multilin 745 Series Advanced Transformer Protection & Management Relay

Description

Technical Specifications

• Manufacturer: GE Multilin (GE Vernova / GE Grid Solutions)
• Model: SR745-W2-P5-G5-HI-A
• Series: 745 Transformer Protection System
• Application: 2-Winding Transformers, Autotransformers, Shunt Reactors
• Control Power: 70–265 VAC (48–62 Hz); 90–300 VDC (wide-range universal input)
• Current Input: 5 A nominal (CT secondary); 0–1000 A primary (via CT ratio)
• Voltage Input: 60–120 VAC (VT secondary); up to 273 V continuous output
• Display: 40-character enhanced LCD (A-type); LED status indicators
• I/O Configuration (P5):
  • Digital Inputs: 16 (configurable, 24–250 VAC/DC)
  • Digital Outputs: 8 (form A/B, 5 A @ 250 VAC resistive)
  • Analog Inputs: 4 (RTD: 3-wire 100Ω Pt/Ni, 120Ω Ni)
  • Analog Outputs: 2 (0–1 mA / 4–20 mA; 600Ω @ 4–20 mA, 10kΩ @ 0–1 mA)
• Communication Interfaces:
  • Standard: RS-232, RS-485 (Modbus RTU)
  • Optional: IEC 61850 (GOOSE/MMS), DNP3, Ethernet (10/100 Mbps)
• Protection Functions:
  • Differential: High-impedance (HI) biased differential, CT ratio mismatch correction
  • Overcurrent: Phase/ground inverse/definite time, directional, restricted earth fault (REF)
  • Overvoltage/Undervoltage: 50/59, 27/59; overexcitation (V/Hz) protection
  • Overload: Thermal (RTD-based), winding/iron core temperature monitoring
  • Miscellaneous: Breaker failure, reclosing, fuse failure, trip circuit supervision
• Accuracy Class: ±0.2% (metering), ±0.5% (protection)
• Operating Temperature: -40°C to +60°C (-40°F to 140°F)
• Storage Temperature: -40°C to +80°C (-40°F to 176°F)
• Humidity: ≤95% RH (non-condensing)
• Protection Class: IP40 (front panel), IP20 (rear panel)
• Dimensions (H × W × D): 228.6 mm × 177.8 mm × 184.2 mm (9” × 7” × 7 ⅛”)
• Weight: 4.8 kg (10 lbs 8 oz)
• Mounting: Standard 19” rack / panel-mount
• Certifications: CE, UL 508, CSA C22.2, IEC 60255, IEEE C37.90
• Status: Active (in production; supported by GE EnerVista 745 software)

Key Features

1. High-Impedance (HI) Differential Protection: Eliminates CT saturation issues, provides sensitive and secure internal fault detection for windings, ensuring stability during external faults and fast tripping for internal short circuits.
2. 2-Winding Per Phase Design: Optimized for dual-winding transformers, supports independent CT/VT inputs for primary and secondary sides, enabling precise differential and overcurrent protection coordination.
3. P5 High-Density I/O: 16 digital inputs, 8 digital outputs, 4 RTD inputs, and 2 analog outputs accommodate extensive monitoring and control requirements, reducing the need for external auxiliary relays.
4. G5 Advanced Firmware: Incorporates dynamic CT ratio mismatch correction, adaptive overexcitation protection, and thermal model-based overload protection, enhancing protection accuracy and system stability under varying load and fault conditions.
5. Enhanced 40-Character LCD (A-Type): Delivers clear, real-time display of metering values, fault records, and relay status; paired with an expanded keypad for intuitive setpoint configuration and local operation.
6. Comprehensive Thermal Monitoring: Supports 3-wire RTD inputs (Pt100, Ni100, Ni120) for winding, core, and oil temperature monitoring, preventing overheating and extending transformer service life.
7. Multi-Protocol Communication: Native Modbus RTU (RS-485), RS-232, and optional IEC 61850/Ethernet enable seamless integration with SCADA, DCS, and asset management systems for remote monitoring, control, and data logging.
8. Extensive Fault Recording: Captures up to 1000 fault events with time-stamped waveforms, event logs, and disturbance records, facilitating post-fault analysis and root-cause identification.
9. Robust Environmental Performance: Operates reliably in -40°C to +60°C temperatures and 95% non-condensing humidity, with IP40/IP20 protection against dust and moisture, suitable for harsh substation and industrial environments.
10. EnerVista 745 Software Support: Compliant with GE’s EnerVista 745 configuration and monitoring software, enabling easy setpoint management, real-time data visualization, firmware updates, and report generation.

Applications

• Power Utilities: Protection and monitoring of transmission/distribution transformers in substations, ensuring grid stability and reliable power supply.
• Industrial Power Plants: Safeguards main and auxiliary transformers in thermal, hydro, nuclear, and renewable energy power stations.
• Oil & Gas: Protects transformers and reactors in refineries, pipelines, and offshore platforms, withstanding harsh environmental and electrical conditions.
• Metal & Mining: Ensures reliable operation of transformers in steel mills, smelters, and mining facilities, handling high inrush currents and heavy industrial loads.
• Critical Infrastructure: Deployed in data centers, hospitals, airports, and government facilities to protect mission-critical power transformers and ensure uninterrupted power supply.
• Commercial Buildings: Manages and protects large distribution transformers in high-rise buildings, shopping malls, and commercial complexes.
• Retrofit & Upgrading: Direct replacement for legacy transformer relays in existing installations, providing modern digital protection and communication capabilities without major system redesign.

System Compatibility

• Compatible Transformers: 2-winding power transformers, autotransformers, and shunt reactors (500 kVA to 100 MVA).
• CT/VT Compatibility: Works with standard 5 A CT secondaries and 120 V VT secondaries; supports wide CT/VT ratio ranges.
• Software: GE EnerVista 745 (configuration, monitoring, firmware updates).
• Network Integration: Connects to SCADA/DCS via Modbus RTU, IEC 61850, or DNP3; supports peer-to-peer communication with other GE Multilin relays.